Blood Types 102: The Role of A, B, O, and AB Groups In Determining Paternity

Hello Doc, Is there any way of determining the father of a child before it is born?
Jamaica

Dr. Greene’s Answer:

Having a baby is a lifelong responsibility and hopefully an even greater reward — for somebody! As a mother’s belly swells, she knows with deep certainty that the child is hers. Each time the baby moves or kicks, the bond between her and her child grows.

Depending on the situation, the father may be pretty sure that the child is his. For most of history, though, dads have had to rely on circumstantial evidence as the foundation on which to build this crucial relationship. After the baby was born, he could feel more sure he was the dad if the baby looked like him (“He has your feet, Honey!”), but often these early resemblances are at least partially creative imaginations.

In 1901 biologist Karl Landsteiner distinguished between three types of blood — groups A, B, and O. A fourth group — AB — was discovered a year later by another research team. As the inheritance patterns of these blood groups were worked out over the next decades, it became possible to include the use of blood type in determining paternity by excluding some men from being the fathers of some children. For instance, if the parents both have blood type O, then the children must all have blood type O. If a child were to have blood type A, B, or AB, then the presumed father must not be the real father. If the child’s blood type were O, then the presumed father might be the real father — but so might millions of other men.

Using Blood Type in Determining Paternity:Possible and Impossible Situations

Parents’ Blood Types

Possible Children

Impossible Children

A & A

A, O

B, AB

A & B

A, B, AB, O

none

A & AB

A, B, AB

O

A & O

A, O

B, AB

B & B

B, O

A, AB

B & AB

A, B, AB

O

B & O

B, O

A, AB

AB &AB

A, B, AB

O

AB & O

A, B

AB, O

O & O

O

A, B, AB

 

These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible.

Today there are over 600 blood types known (as well as other tissue types called HLA types), which can make paternity testing far more accurate — but still not perfect.

Determining Father Before a Baby is Born

It is also now possible to determine the father before a baby is born. This is done by comparing DNA molecules — our genetic blueprints. To do this you need a blood sample from both the mother and the potential father (testing without the mother’s blood is possible, but more difficult — and more expensive). You also need a small sample of amniotic fluid (the water that the baby is floating in). Less than 1/4 teaspoon is sufficient for the test. The amniotic fluid may be obtained by a process called amniocentesis. This procedure is performed no earlier than 13 weeks into the pregnancy.

A court order or informed consent of all adults involved is required to proceed with paternity testing.

You will need to wait 3 to 4 long weeks for the results. Waiting for these test results can be a very anxious time. Rush orders take 10 to 15 business days, but cost about $500 extra.

Either way, if the test says that a man is not the father, then legally and truly he is not (it can absolutely exclude some men as the father of a certain child). If the test says that he is the father, then he probably is — there is about a 99.8% chance that he is. DNA testing is now legally accepted as able to determine paternity.

There are about one million two hundred eighteen thousand five hundred males in Jamaica (as of 1992). A positive DNA paternity test could limit the potential fathers to only about 2,437 of them (plus 0.2% of the tourists). Only 2 out of 1000 men could possibly be the father. As you can see, a positive paternity test is good evidence, but not an ironclad guarantee.

Paternity Testing

Prenatal paternity testing can be arranged through a company called Genelex, located in Seattle, Washington. They are very helpful, and can be reached at 1.800.523.6487 or healthanddna.com. The test costs $700.

If you wait until after the baby is born, DNA testing can be arranged through most local blood banks (many of which use Genelex). The blood sample can be obtained at birth. Otherwise, the baby should be at least 2 months old, since a fair amount of blood is needed for the test. In my area, this option costs about $600.

I realize that the circumstances that prompt a person to undergo paternity testing are often difficult. I hope that whatever you want turns out to be true. Even more, I hope that whatever turns out to be true becomes something that you learn to want.

Dr. Alan Greene

Dr. Greene is the founder of DrGreene.com (cited by the AMA as “the pioneer physician Web site”), a practicing pediatrician, father of four, & author of Raising Baby Green & Feeding Baby Green. He appears frequently in the media including such venues as the The New York Times, the TODAY Show, Good Morning America, & the Dr. Oz Show.

  1. Elizabeth G

    Hi, I was wondering if I’m O- and my mother is B+ what could my dads blood type be?

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    • Hi Elizabeth,

      Great question. As it turns out, if you’re O- and if your mother is B+, your father could be O+, O-, A+, A-, B+, or B-. He could not be AB+ or AB-.

      Let me know if you’d like an explanation.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  2. chitra

    Hi, is it possible to get a child with blood group o+ while the parents is ab+ and O+

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    • Chitra,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be AB+, the other parent to be O+ and their child to be O+. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  3. Halie

    If my boyfriend is A + and I am O – what will our babies blood type be?

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    • Hi Halie,

      Thanks for writing in.

      If you are O- and if the father of your baby is A+, each of your children could be A+, A-, O+ or O-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  4. Craig

    My group is ab possitive and wifes group b possitive what is the possibilities of childs group.

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    • Craig,

      Thanks for writing in.

      If your blood type is AB+ and the mother of your children’s blood type is B+, each of your children could be AB+, AB-, B+ or B-.

      If you would like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  5. Anonymous

    Hi doctor, I’m RH Negative (O Negative) Our son is A positive and I Don’t remember but I thought our daughter was B positive or AB positive I can’t remember! We don’t know what my husbands blood type is! Could you please tell me what his blood type could be based on our children?

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    • Anonymous,

      Thanks for writing in.

      If you are O-, your child can not be AB+ or AB-. Let’s assume you daughter is B+ (but remember, unless you’ve had a confirmed blood type, you may not be O-, so this is all an exercise in “what-if’s”). But if you’re O- and if you have one child who is A+ and one child who is B+, their father would have to be AB+.

      If you’re O- you can only pass down an O and a -. That means each of your children had to get the + from their father and had to get either the A or the B from their father.

      Again, this is just a “what-if” until you are sure of your blood type and each of your children’s blood type.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  6. Misty

    I am O+ and my husband is O-. What blood type would our children be?

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    • Hi Misty,

      Thanks for writing in.

      If you are O+ and the father of your baby is O-, the children can only be O+ or O-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  7. Renée

    Hi Dr, My blood type is o+ can my father be AB blood type. I don’t know my mother’s blood type.

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    • Renée,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be AB have a child who has type O blood. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  8. William

    Hi , my blood is O- I want to knw if it’s true that O- are likely to give birth to twins

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  9. Pat

    Hello Dr Greene,

    My mom is O+ and we believe that my biological father was AB. We are not sure about the RH. I have a sister that is AB+ another sister is O+ and I am O-. I also know that my mom has a sister that is O-. So my question is, are my sisters and I full sisters or do I have a different father?

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    • Pat

      I apologize, my sisters are B+ and O+ and we are unsure of our father’s blood type.

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    • Pat,

      Thanks for writing in.

      If your mother has type O blood, she can not have a child with type AB blood no matter what the father’s blood type. Additionally, if your father had type AB blood, he can not have children with type O blood.

      From your question it sounds like your father is no longer living. That complicates things a bit, but it would be wise to have all your blood types retested. For instance if one of your parents is type A and the other is type B, all of the blood types of the children you mentioned are possible.

      I hope that’s helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  10. Michelle

    My mother is A+ and my father O+ I’m O- is this possible?

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    • Hi Michelle,
      Yes, this is possible.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  11. Pn

    Hello Dr.

    My Wife’s Blood group is O Positive and My Blood Group is B Positive, My Daughters Blood group is seen as AB Negative, Is this possible?

    Pn

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    • Hi Pn,
      Thanks for writing in! Our current understanding of genetics is that it is not possible for one parent to be O, the other parent to be B and their child to be AB. It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  12. T

    My mums B- and my dad is O- what is my blood type?

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    • You should be either B- or O-, if your parents’ blood types are correct.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  13. Tara

    I am A positive and my husband is A positive can my child be A positive?

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    • Hi Tara,
      Yes, this is possible!
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  14. Pat

    Hello,
    I just had my blood retested and came back O+, I have been told my husband is A (not sure + or -), was told my daughter (at her birth) is AB (?) and son is B (?) how can this be?
    Thank you……

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    • Hi Pat!
      Hmm that doesn’t sound possible based on our current understanding of genetics. Probably a good idea to get your husband and children retested too.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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      • Pat

        OK, just got word from daughter saying she gave blood recently and is O-(she was told), NOT AB as the Dr. told me back when she was born. How could they have made such an error? They even stressed how rare her type was!

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  15. Jeryll

    Hi,

    I have blood type o and my wife is blood type o but my new born baby is AB. Is that possible?

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    • Hi Jeryll,
      Our current understanding of genetics is that it is not possible for both parents to be O and their child to be AB.
      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  16. Vicki

    My mother is a o- rh factor my father is b+ what blood type should I be

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    • Hi Vicki,
      Thanks for writing in! You would be O or B, + or -.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  17. Emma

    Hello, in desperate need off your help! So my partner is from Pakistan we have been having a really hard time with his family and split up I stupidly slept with another guy, who is English.. I’m now pregnant is there anyway by bloods I can tell who’s baby this will be? (My child us unborn) please help it’s sending me insane.

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  18. ASIM CHANDA

    if child have A and mom have AB , then what is the possible blood group pf dad??
    is it….all i.e A,B, AB and O??

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    • Hi Asim,
      Thanks for writing in! Yes, given your scenario, the dad could be A, B, AB, or O, and still have a child who is A.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  19. Olivia

    Hello. My mom has O+ blood type and my dad has B+ blood type so I was wondering what kind of blood type I most likely have

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    • Hi Olivia!
      Given your parents’ blood types, you are most likely O or B, and you could be + or – depending on whether your parents carry the Rh- type as well as the Rh+.
      To be sure, you could just get a quick blood test done.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  20. Tere

    Hi Dr. Green.
    I am a teacher, and at school, there was a huuuuuge controversy. When the science 7th grade teacher showed a blood paternity chart (exactly as the one that you present on this site), a student almost freaks out because she is AB, and her mom and dad are A.
    Then, parents came wanting to sue the school for that (fortunately they finally didn’t) but still the dad made a terrible scene accusing his wife of infidelity here at school.

    Are there any exemptions that could possibly be: mom A + dad A = child AB?

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    • Hi Tere,
      Thanks so much for writing in! How stressful for your student to have her parents so upset over the blood paternity chart.

      Our current understanding of genetics is that it is not possible for both parents to be A and their child to be AB. It is wise to have all their blood retested before jumping to conclusions. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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      • Tere

        Thanks Alexandra.

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  21. Linda

    My mom was 0- my dad is 0+ how can I be a+

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    • Hi Linda,
      Thanks so much for writing in! Our current understanding of genetics is that it is not possible for both parents to be O and a child to be A.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  22. Samantha

    I’m a+ and my boyfriend is o positive my son is a+ is this my boyfriends son?

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    • Hi Samantha,
      Thanks for writing in! It’s definitely possible that an A+ mom and O+ dad can have an A+ baby, yes.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  23. Blanca

    is it possible to find out my husbands blood type with my kids and my blood type? I am o+ and my kids are o+ and b +

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    • Hi Blanca,

      If you are O+ and your if your kids are O+ and B+, he is either B+, B-, AB+ or AB-. You can’t get closer than that without having his blood type tested.

      Hope that helps,
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  24. Akriti

    my blood group is A+, my dad’s B+. what would be my mom’s blood group?

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    • Joe

      Your mom must be A or AB. She cannot be B or O if you’re A and your dad is B.

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  25. Twinkle

    I am B Positive my daughter is 0 Negative

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  26. Andres

    My mother is O- and my father is B+. My blood type is B-. Is he my father?

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    • Hi Andres,
      Thanks for writing! It is possible for an O- mother and a B+ father to have a B- child, yes.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  27. Jeamy

    I’m O pos. My husband is B pos. And our baby is AB how is that possible???

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    • Hi Jeamy,
      Thanks so much for writing in! Our current understanding of genetics is that it is not possible for one parent to be O+, the other parent to be B+ and their child to be AB. One parent would need to be A or AB to have an AB child.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  28. K

    Both parents are o but son is b reh+

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  29. Aditi

    My blood group is B negative but my parents blood group is B positive. Is this possible ??????????????????????????????????????

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  30. Mayur

    Dear sir my blood group is o positive and my wife blood group is o negative and my child is b positive it is possible

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    • Hi Mayur,
      Thanks so much for writing in! Our current understanding of genetics is that it is not possible for both parents to be O and the child to be B.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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  31. Bianca

    Hi doc,

    U sau it is impossible for 2 O parents to have an A baby. . . i think its not true reasons being:
    1) I have only ever slept with 1 man
    2) my child looks too much like me to be switched ay birth
    3) my dad is A type. . .

    so how can my son be A then if its “impossible”?

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    • Hi Bianca,
      Thanks for writing in! Our current understanding of genetics is that it is not possible for two O parents to have anything other than O children.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

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    • Sandy

      It is practically and scientifically not possible to have a B+ baby when both parents are O blood group.

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  32. Oshin

    Hello sir
    My blood group is o+ and my husband’s is b+ but my son’s blood group is a+.according to the chart it’s impossible.does it happen in rare case?
    Thank you.

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    • Oshin,

      ur current understanding of genetics is that it is not possible for one parent to have O+ blood, the other parent to be B+ and their child to be A+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  33. A.M.S

    I am A-, during my pregnancies I had to have injections of Rogham. I understand the reasoning behind that, because if the father was + the affects it would have on me. Now, my question is this. My mother is also A-, and again I am A-, which would mean my father couldn’t be a + correct? Because if he was then that would of been passed on to me? What would his blood type have to be for me to be A- coming from a mother that is also A-?

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    • Hi Amy,
      Thanks so much for writing in! It’s a great question. Based on what Dr. Greene wrote here (http://www.drgreene.com/understanding-blood-types/), your father could have been Rh- or Rh+ (technically — or +-, so he could pass the – on to you). Feel free to read it for yourself as well.

      I hope that helps! Best wishes,
      Alexandra (caring helper at drgreene.com, but not a doctor)

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  34. lena

    I am AB +, one son is A+ and one son is B+. Their father is O. Could he be + or – ?

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    • Hi Lena,
      Thanks so much for writing in! Great question. Based on Dr. Greene’s article here (http://www.drgreene.com/understanding-blood-types/), it sounds like yes, the father can be + or -. Feel free to read it for yourself as well.

      I hope that helps! Best wishes,
      Alexandra (caring helper at drgreene.com, but not a doctor)

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  35. Concerned

    My mom is AB- and I am A+ what is my Father’s blood type.

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    • Dear Concerned,

      If your mom is AB- and if you are A+, your father can be A+, B+ or O+.

      Let me know if you’d like more explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  36. Jade

    I’m an Ab+ and my husband is B+.
    Which blood group will our baby belong?

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    • Hi Jade,

      If you are AB+ and your child’s father is B+, each of your children could be AB+, AB-, B+, B-, A+, or A-.

      Please let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  37. Eloise

    My parents are both 0+ and im 0 -. …

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    • Eloise,

      I can see how you’d be concerned, but it is normal for two O+ parents to have an O+ or an O- child. You can rest assured.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  38. Gabrielle

    Both our children are o negative as am I, what blood type is my husband.
    Does blood types affect our children’s gender? We have two sons

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    • Gabrielle,

      If you are O- and your children are O-, their father could be O+, O-, A+, A-, B+, B-. He could not be AB+ or AB-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  39. Ayush Agarwal

    Is it necessary that bombay blood type child form only in inbreeding ?

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    • Ayush,

      The Bombay Blood type is rare and is only found is some people. Both parents do not have to be related to have the hh allele, but it is more likely in some groups than in others.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  40. Sunflower

    I am 0 positive my 2 girls are also and my one daughter is a- what could there dad be

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    • Sunflower,

      If you are O+ and one of your children is A-, her father could be A+, A-, AB+ or AB-.

      Let me know if you’d like more explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  41. Ayush Agarwal

    Sir both me & my brother have O+ blood group while my father has blood group O+ while mother has blood group AB+.
    They both are my biological parents. then how it is possible?As according to your above chart its impossible to have O+ blood group?

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    • Ayush,

      There is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      The Bombay blood type is usually only found in small communities where there are other people with the hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

      If you suspect you may have the Bombay blood type talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

      DNA paternity tests are still accurate (99.999%) with Bombay type blood and are considered the only accurate test for paternity.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  42. Luwe

    Hi my blood type is B+ my husband is O ,but i dont know the Rh,what would our child might have blood type

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    • Hi Luwe,

      If you have type O (Rh+ or Rh-) and your baby’s father has B+ blood, your child could be B+, B-, O+ or O-.

      Let me know if you’d like further explanation.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  43. Minda Vazquez

    My husband has always wondered, if he is O – and I am A-, all our children are A- , why aren’t any of our children O-

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    • Hi Minda,

      If both you and your children’s father are Rh-, all your children will be Rh-.

      Statistically, if you are A and your children’s father is O, 25% of your children would be type O. In other words each child has a 1 in 4 chance of being A-, which means each child has a 75% chance of being A-. Theoretically, if you had four children, one would be O-, but these odds really only play out over a large sample size. i.e. if 1,000 children had parents who were O- and A-, 250 of them would be O-, but the first 750 could easily be A-.

      Does that make sense to you?

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  44. cortney johnson

    my name is cortney, hi, i have a question,
    my blood is A- my husbands is AB+ and our baby is AB-
    is this a rare thing

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    • Cortney,

      If one parent is A- and the other is AB+, there is a 37.5% chance their child will have type AB blood and a 25% chance the child will be Rh-.

      I hope that answers your question.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  45. Cortney

    Iam A- the father is Ab+
    Our baby is AB- why is this ?

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    • Cortney,

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O. Each person also has two Rh alleles that can be positive (+) or negative (-).

      If a person has type A- blood he or she has at least one A allele (this can be AA or AO) and has two negative alleles (- -).

      If a person has type AB+ blood he or she has one A allele and one B allele and at least one positive allele (this can be ++ or + -).

      In the example you provide the A-, could be AA- – or AO – -. The AB+ parent could only be AB+-.

      The child would have gotten an A from the A- parent and a B from the AB+ parent and a negative from each parent.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  46. Sarah

    I am A- , my mom is O+. Could my dad be B+?

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    • Sarah,

      Our current understanding of genetics is that it is not possible for one parent to be A-, the other parent to be O+ and a child their child to be B+. These two parents could only have children who are O+, O-, A+ or A-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  47. Vela

    I am B+. My mother is O (I’m not sure the RH). What would that make my father? He has to be B, right?

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    • Vela,

      If your mother is O and you are B, your father is either B or AB. If you are B+ at least one of your parents is Rh+. They could also both be Rh+, but they can not both be Rh-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Dorcas Jones

        What does ob positive means
        And what if me and husband and four children has the same

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  48. annie

    my husband is a positive, me is b positive, and my child is b positive too.. is it right?

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    • Hi Annie,

      If one parent is A+ and the other parent is B+, their child can be B+.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Michelle

        Hi sorry I’m the same as this . My boyfriend is panicking over blood group about some not being good together when having children X couple you please explain a bit
        Thank you

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        • Michelle,

          If the mother is Rh- and the father is Rh+, there can be a problem for pregnancies after the first. Dr. Greene wrote about this –> How To Determine and Manage Rh Incompatibility. Do you know your blood types?

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  49. Deepmala

    Hiii.
    My blood group is B+ and my husband is O+ and my baby is AB+ how its possible

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    • Deepmala,

      Our current understanding of genetics is that it is not possible for one parent to be B+, the other parent to be O+ and a child their child to be AB+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Michael

        Both my parents are O+, my older brother is B+ my younger brother is O+, I am AB+. How is this possible? We tested 3 times.

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        • Michael,

          Our current understanding of genetics is that it is not possible for two parents to be O+, and their children to be B+ and AB+.

          Have you discussed this with your parents? If you’ve had your blood types retested, perhaps it’s time to have DNA paternity testing done.

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  50. Cathy

    My parents both were O+ . My sister and I are both A + how is that possible?

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    • Cathy,

      Our current understanding of genetics is that it is not possible for both parents to be O+ and their child to be A+. Two O+ parents can only have children who are O+ or O-.

      It is wise to have all your blood re-tested. It’s not uncommon for blood types to be different than they are thought.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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    • alycia

      It’s genetic mutation…that’s how..it’s rare but it can happen. O blood type used to be A blood type..it’s missing one allele. During the genetic code (inception of a baby) if that one allele is placed back then the O blood would return to an A blood type.

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  51. Kathy L Gladson

    If my mom is RH o – and my dad is a – is it possible for my brother to be a+ when my two sisters are a- and I’m RH a-

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    • Kathy,

      Our current understanding of genetics is that it is not possible for one parent to be O- and the other to be A- and their child to be A+. Two Rh- parents can only have children who are Rh-.

      It is wise to have all your blood re-tested. It’s not uncommon for blood types to be different than they are thought.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  52. Anna

    My husband is o- and my son is o+. What would that make me the mom?

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    • Anna,

      If your son is O+ and if his father is O- you could be O+, A+, or B+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  53. Tammy

    Me, my sister and a niece from a deceased sister are O-negative. What are the odds that my parents were both Rh negative?

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  54. tieba

    my mom is o postive and dad is ab what would my blood type would be

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    • Tieba,

      If your mom is O+ and your dad is AB, you could be A+, A-, B+ or B-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Jessica

        Hey there my dad is A+ and my mom is A-. I’m curious about what my blood type might be. Thanks!!

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        • Hi Jessica,

          If your dad is A+ and your mom is A- you could be A+, A-, O+ or O-.

          Let me know if you’d like an explanation.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  55. Liline

    Hi Doc, I’m A+ and my three kids are A+, what do you think my husband blood type might be if all our three kids are A+ ?

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  56. Dineshwaren

    Hello I am Dineshwaren ,my father blood group is O and my mother is A,what is my possible blood groups and the siblings can have same blood group?

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    • Dineshwaren,

      If your father is blood group O and your mother is blood group A, each of their children can be A or O.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  57. Ankur

    My blood type is A+ and my wife is AB-. So is there any problem during her pregnancy? What is the possible blood group of our children? Please let me know.

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  58. Jonathan

    Hello doctor I was wondering is I’m o+ and my girlfriend o+ can our baby be born with complications

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    • Jonathan,

      If one parent has O+ blood and the other has O+ blood, the baby won’t have issues with blood type incompatibility. There can be complications for other reasons, but not from blood types.

      I hope that helps, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  59. Carol Lockridge

    Hello, My mother once told me she was AB+. I never physically met my dad but I think he was an O. My blood type is O+. Im confused, am I supposed to be type O?

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  60. Yaszher A. Laborte

    Hello doc I have a question of my mother blood type is A/B and my father is type B . What are the possible blood type of their offspring?

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    • Yaszher,

      If your mother is AB and your father is B, each of their children could be AB, B or A.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Heaven

        Hello, my mom’s father is O- and my mom is ab+
        I do not know my grandmother’s blood type. My mother is convinced that her father may not actually be her real father because he is O-.
        Is her assumption logical?

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        • Heaven,

          If your mom is AB+ neither of her biological parents can be O-. But it’s not uncommon for blood types to be different than remembered. Before jumping to any conclusion it would be wise have blood types retested.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  61. Nat

    Hi, I’m A- and I’ve just found my Dad, I’ve never met, his blood type is B+ I’m pretty sure Mum was A or A+ is that possible?

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    • Nat,

      Yes it is possible for a type A- or A+ mother and a type B+ father to have a child who is A-.

      If you’d like an explanation, let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  62. gaby

    Again I ask i am A- the father is O+ my son is A- is that possible?

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    • Gaby,

      If the mother is A- and the father is O+, their child can be A-.

      Sorry if I missed an earlier question.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  63. GARIMA

    Hi,
    A father with B+ve and a mother with A+ve can have a child of AB-ve

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    • Garima,

      Yes, it is possible for a father with B+ blood and a mother is A+ blood to have a child that is AB-. If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  64. Fredi

    If i am A- and my father A+ what should my mother be??

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    • Fredi,

      If you are A- and if your father is A+, your mother could be O+, O-, A+, A-, B+, B-, AB+, or AB-. In other words, this is one of those combinations that doesn’t rule out your mother being any blood type.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  65. Holly

    Hello if a mans bloods type is O- and the mothers type is B+ is it possible for the baby to have A- blood type?

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    • Hi Holly,

      It is not possible for a mother to have B+ blood, her baby to have A- blood and the father to have O- blood.

      If the mother’s blood is B+ and the baby’s blood is A-, the father is A+, A-, AB+ or AB-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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    • Ruprekha waghmare

      Ruprekha

      If mother is B positive and father is O positive.It is possible child have A positive blood group

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  66. Gorge

    My wife is 0- our son is O- an Ather possible father to my son is O- could he be the father ?

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  67. James

    I’m curious what happens if two ab- people have a child (I heard it would cause problems)

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    • James,

      I am unaware of any special risk for two type AB- people having a child. Perhaps you’re thinking about an Rh- mother and an Rh+ father. There is an incompatibility issue with that combination.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  68. Scotty stiltner

    My blood type is abpositive, my wife is o negative,. What would our son’s be?

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    • Hi Scotty,

      If the dad is AB+ and the mother is O-, each of their children could be A+, A-, B+ or B-. No children can be AB+, AB-, O+ or O-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Hector F. GarzaMata

        Hi! My blood type is A- But my father had O+ and my mother was A+ .. and out 8 siblings only a sister has O-, all others are positives. Is it possible that we (my sister and I) inherited rh negative gene from paternal grandmother who was O-? or that can`t be?
        On my children, two came with A- and O- and one with my wife´s type A+.

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        • Hector,

          Blood types are passed down from parents, not grandparents, but it is possible for a person with Rh+ blood to have either two – alleles (- -) or one – and one + (+ -). If both your parents were +-, and if they each passed down the – allele to you and your sister, then you would be Rh- (- -).

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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    • Gary

      My blood group is 0+ my wife is 0+
      She slept with a guy that is B+
      The child is born 0+

      What are the chances that this is his kid?

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  69. Shreejita Mitra

    Parents blood type o+ and their 1st child’s blood type a+…how is it possible?????

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    • Hi Shreejita,

      If both parents are O+, they can not have a child who is A+. It is possible that one of the three types is different than thought. Re-testing is the best next step.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  70. Shreejita Mitra

    Parents blood type o+ and their 1st child’s blood type a+…how is it possible?????

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    • Shreejita,

      If both parents have O+ blood, each of their children will be O+ or O-. They can not have a child with A+ blood.

      It is common for blood types to be different than thought. The next step is to re-test both parents’ and baby’s blood types.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  71. Leslie Berry

    Hi, I’m a positive and my husband is O negative. Was curious if this could cause an incompatibility in my pregnancy. I have been experiencing bleeding.
    Thank you

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    • Leslie,

      I’m so sorry to hear you’re having difficulties. I hope you’ve been in touch with your Ob about this.

      The concerns over blood type incompatibility are only if the mother is Rh- and the father is Rh+, so this is not an issue for you.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Babe

        So what would a baby of that combination have? I mean A+ mother and O- father

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        • Hi Babe,
          If one parent is A and the other parent is O, our current understanding of genetics is that any children can only be A or O, but they could be + or -.

          Hope that helps!
          Alexandra (caring helper at drgreene.com, not a doctor)

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  72. Neeshu

    Hi. I am A+ and my wife is AB+ we had a daughter with B+ blood group. Is it possible to have different blood group of children apart from their parents? Please explain if possible isn’t their any medical complications in such children? As my daughter is suffering from many problems since she was born I am confused. Please help and advice.

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    • Neeshu,

      Yes, it is possible for the father to be A+ and the mother to be AB+ and the child is B+. I don’t know of any medical conditions associated with this combination.

      If you’d like further explanation, just let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  73. Ker

    My blood type is O+ while my wife’s type is AB+. How come our daughter’s blood type become O+. It was in the “impossible” list. Can I get more explanation? Can she fall in to the so called “bombay” blood group?

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    • Ker,

      If one parent is AB and the child is O, an explanation is the Bombay Blood type. The typical A, B, O blood tests read the hh type (Bombay) as O.

      You can ask your doctor to help you find a lab that can test for the Bombay blood type. It’s very rare and not many labs can run the test, but it’s valuable information to have. Individuals with Bombay blood type can not receive transfusions from anyone with A, B, O or AB blood types.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  74. Anna

    Hello,
    I’m AB- I do not know my parent’s blood type but am concerned because my mom doesn’t recall doing anything in the late 1960’s or early 1970s when she was pregnant with either my sister or I. I had to do the shots when I was pregnant because I was AB- (luckily it didn’t matter because my child is AB-).
    My sister is Type O.
    Is this possible that my sister type O and I’m AB- and we have the same parents?

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    • Anna,

      Yes, it is possible for one sibling to be AB and the other to be type O. If your parents are type A and B, they could have children who are AB, A, B, or O.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • gkpl

        I was O positive in childhood but now iam A positive.My parents are O positive iam really confused,is there any rare chance?

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    • sanjay

      Sanju

      Hay
      My blood group is b+ve and my wife a+ve my daughter is b-ve. Is it possible.

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      • Sanjay,

        Yes, if you are B+ and your wife is A+, your child could be B-. This is perfectly normal.

        If you’d like an explanation, please let me know.

        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  75. Monika

    Hi doctor, My husband and I are same type O+, what would my baby be? Thanks you so much

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    • Monika,

      If both parents are O+, each of their children could be O+ or O-.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  76. Darla

    My father is AB- and my mother was B+, yet I am Type O-.

    My husband is B+ and I am, as stated above O- but our daughter is type AB-.
    (as a side note, she was the pregnancy I did not feel really ill with, my other children who are all type O-,O+ with were rough)

    I know that this defies traditional blood type rules and I have researched a bit and have read about Cis-AB, where at some point in our lineage, the A and B may have become fused together, leaving an empty or “O” space, which I inherited and in fact passed to some of my children. Perhaps I am not actually “O” but test as “O” having some faded A or B. ( I am not a geneticist, can you tell? lol) We are not Chinese or Japanese but a mix of European ancestry, with a bit of Native American. I would like to get a test that explains this in case of health issues or some future paternity or maternity test. What test might you recommend?

    Thank You for your time.

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    • Darla,

      There is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      If you suspect you or your child may have the Bombay blood type talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests. The tests may vary based on where you can go to be tested, but ask you doctor to help you determine where to go and which test they will use.

      If you or your children are Bombay blood type, you can not get blood that is A, B, O or AB, so it’s very helpful to have this information while you are all healthy.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  77. Rosa

    Im not sure what my blood type is but my daughter is b+ and her father is o+.. What would that make me.

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    • Rosa,

      If your daughter’s blood type is B+ and if her father’s blood type is O+, you could be B+, B-, AB+ or AB-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  78. Joseph

    My girlfriend is o+ and her newly born son is o+. What would the fathers blood type have to be?

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    • Joseph,

      If the mother’s blood type is O+ and the child’s blood type is O+, the father could be O+, O-, A+, A-, B+ or B-. He could not be AB+ or AB-.

      Let me know if you’d like an explanation.

      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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      • Joseph

        Where and how easy is it to find my blood type

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        • Hi Joseph,

          Blood types are pretty easy to get. Here are a few ways:
          1) Ask your doctor for a test — costs about $200
          2) Order a home kit (I suggest you order two per person so you have a backup) – less than $10 per kit
          3) Donate blood at the Red Cross or other Blood Bank — FREE and you get the satisfaction of helping other people

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  79. Nikki

    Hi, if both patents are positive how does baby end up negative? So mom is O+ and Daf is N+ and baby is O-…

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    • Nikki,

      Each person also has two Rh alleles that can be positive (+) or negative (-).

      1) If a person is Rh+ he or she can have two + alleles (+ +) or one + and one – (+ -).
      2) If a person Rh- he or she has two – alleles (- -).
      3) If both parents are Rh+ (+ -), they can both pass down the – allele so their child has two – alleles (- -) and is Rh-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  80. Dana

    Hi , if i am AB with RH negative and my husband is 0 positive can we have a baby with a negative Rh?what would our baby be?thank u very much

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    • Dana,

      If you are AB- and the father of your baby is O+, your baby could be A+, A-, B+, or B-. Your baby could not be AB+, AB-, O+ or O-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  81. lacey

    Hi Im O+ and my Husband is A+ what is my daughters blood type

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    • Hi Lacey,

      If you are O+ and if your daughter’s father is A+, your daughter could be A+, A-, O+ or O-. She could not be B+, B-, AB+ or AB-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  82. Annie

    Im B+ and my baby is AB+, what tipe of blood is my husband, AB+? Thank you :)

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    • Annie,

      If you are B+ and if your baby is AB+, your baby’s father could be AB+, AB-, A+ or A-. He could not be B+, B-, O+ or O-.

      Let me know if you would like an explanation.

      Best, @MsGreene
      Note: I reply to a lot of the comments on DrGreene.com. I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  83. David...

    Hi i am ab- and my wife is a+ so what will our child be.

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    • David,

      If you are AB- and your wife is A+, the two of you could have children who are A+, A-, B+, B-, AB+ or AB-. You could not have children who are type O+ or O-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  84. Truleigh

    If one parent is AB- and one is A+ what is likely going to be child’s blood type?

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    • Truleigh,

      If one parent is AB- and if the other is A+, their child could be A+, A-, B+, B-, AB+ or AB-. The child could not be O+ or O-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  85. Kirsty Cooke

    Hi I am ab+ my mum is a resus – what is my dad?

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    • Kristy,

      If you are AB+ and if your mum is A-, your dad is B+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  86. Amna Khan

    If mom has o+ and dad has b+, would child have b+? Or different blood type?

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    • Amna,

      If mom is O+ and if dad is B+, their child could be B+, B-, O+ or O-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  87. Angel

    Can a ab+ and a ab- have ab positive baby ?

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    • Angel,

      Yes, an AB+ parent and an AB- parent can have a child that is AB+.

      If you’d like an explanation, let me know.

      Best, @MsGreene
      Co-founder & Executive Producer, DrGreene.com
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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      • Rebecca

        Out of 6 kids there’s only 1 with a A+Blood type. 3 r A- and 2 r O+ . Can a A- & O+make a A+Blood

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        • Rebecca

          Thank You

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        • Rebecca,

          Yes, if one parent is A- and the other is O+, they can have a child who is A+.

          Let me know if you’d like an explanation.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  88. Sophi

    If the mother is a+ and father is b+ can the. Child be o-

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    • Hi Sophi,

      Yes, it is possible for one parent to be A+ the other parent to be B+ and the child to be O-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Co-founder & Executive Producer, DrGreene.com
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  89. Brandy

    I the mother am o- with a rh negative factor. My son is B+ would his father also be B+?

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    • Brandy,

      If one parent is O- and the child is B+, the other parent could be B+ or AB+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  90. Sherri

    I just had a baby I’m O+ both my girls are A- and the father is AB he’s not sure if positive or negative I need help with that

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    • Sherri,

      If your children are A- and your are O+ and if the father of your children has type AB blood, he could be AB- or AB+. Here’s why:

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O. Each person also has Rh alleles that can be positive (+) or negative (-).

      If a person has O+ blood he or she has two O alleles (OO) and either two + alleles (+ +) or one + and one – (+ -).

      If a person is A-, he or she could have two A alleles (AA) or one A and one O allele (AO) and must have two – alleles (- -).

      If a person has type AB+ blood he or she has at one A allele and one B allele and either two + alleles (+ +) or one + and one – (+ -).

      If a person has type AB- blood he or she has one A allele and one B allele and two – alleles (- -).

      In the scenario you suggested, each child received an A from their father and an O from you. Each child also received a – allele from each parent.

      I hope that helps.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  91. Diane

    My dad is B. My mom is A. My older sister is A. I am 2nd, AB. 3rd is O. 4th is B.

    Is it possible for the O sister to have the same father as us?

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    • Diane,

      Yes, it is possible for an A parent and a B parent to have children who are A, B, AB and O.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  92. Andrew

    Hello,
    Can you settle the debate for my wife and I. If my wife is A+ and I’m O- what blood type can our children be?
    Thank you,
    Andrew

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    • Andrew,

      If your are O- and your wife is O-, your children could be A+, A-, O+ or O-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

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  93. Riz

    My blood type is O+ My husbands blood type is A+ and my daughters blood type is AB+ how is this possible?

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    • Riz,

      If you know who both parent are without a doubt, with this combination likely one of your blood types is different than previously thought. This can be due to an error in the testing or an error in recording. Retesting may be wise.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  94. Carla

    My blood type is ab- and my sons blood type is a+ so what would my son’s fathers blood type be?

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    • Carla,

      If your blood type is AB- and your son’s blood type is A+, his father could be A+, B+, O+ or AB+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

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  95. Ann teneycj

    If parents have 3 kids 1 type A, 1 type B and a third type 0 what is the proabability a fourth child would be AB?

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    • Ann,

      If the same two parents have three children who are type A, type B and type O, we can deduce that the parents are type A and type B. There is a 56.25% that each of their children will be type AB.

      Of interest, there is a 18.75% chance that each child will be type A, a 18.75% chance that each child will be type B and only a 6.25% chance that each child will be type O. So even though in the general population type O is the most common type and type AB is the least common type, for these two parents, it’s the opposite.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

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  96. Cass

    Both my son and I are B+
    Are there any blood type that his father cannot be?

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    • Cass,

      What is your blood type?

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  97. Bky

    Please doctor, can 0 positive father has 0 negative child?

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    • Bky,

      Yes, if a father is O+ he can have a child that is O-.

      Please let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  98. Holly Moore

    Mom is o negative son is o negative so what would be the fathers blood type?

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    • Holly,

      If the mother is O- and the son is O-, the father could be O+, O-, A+, A-, B+ or B-. The father could not be AB+ or AB-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  99. Ejaye

    If a father is o negative and a mother is a negative can the child be A positive

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    • Ejaye,

      It is possible for one parent to have type O blood, the other parent to have type A blood, and their child to have type A blood. But two parents with Rh- blood can only have children with Rh- blood. However, if one parent is Rh- and the other is Rh+, they can have a child with either Rh- or Rh+ blood.

      Since blood types are often different than what they are thought to be, it’s smart to have all three blood types tested again.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am Dr. Greene’s business partner and wife, but I am not Dr. Greene.

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  100. David

    If a mother is A+ and the father is B-, what can the child be?

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    • David,

      If one parent is A+ and the other is B-, each of their children could be A+, A-, B+, B-, O+, O-, AB+ or AB-. Basically, this combination does not rule out any possible outcome.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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      • David

        Thank you Dr. Greene!

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  101. Kimberly

    If a mother is A+ father is O+ can the child be AB+

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    • Kimberly,

      Our current understanding of genetics is that it is not possible for one parent to be A+, the other parent to be O+ and a child their child to be AB+. An A parent can only have children who are A or O.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  102. Tams

    daughter is ab mother is a+what can dad be

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    • Tams,

      If the child is AB and if the mother is A, the father would be type B.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  103. Lori

    Is it possible for my mom to be AB+ and my father O. I am O.

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    • Lori,

      Our current understanding of genetics is that it is not possible for one parent to be AB, the other parent to be O and a child their child to be O. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  104. vinayasree

    Hi am vinayasree
    my moms blood group is o+and my dad’s is o- and I have b+ is this possible

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    • Vinayasree,

      Our current understanding of science is that it is not possible for one parent to be O+, the other parent O- and their child to be B+. Two type O parents can only have type O children.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  105. Shania

    My parents are B+ and O+ and I am A+. Is this possible?

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    • Shania,

      Our current understanding of genetics is that it is not possible for one parent to be B+, the other parent to be O+ and their child to be A+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  106. Zhaan

    Hi Doc,am A+ and my husband is o+,my son’s blood group is A+with a D rhesus which I don’t get where the D is coming from.pls educate me more…

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  107. Yna

    If a mother is type B+ and the father is O+ it is possible the baby will b A+?

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    • Yna,

      Our current understanding of genetics is that it is not possible for one parent to be B+, the other parent to be O+ and a child their child to be A+.

      Please let me know if you’d like an explanation.

      In the meantime, it is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  108. Debbie brown

    Is it possible to have a child B negative when the mother is A positive and the father is B positive
    Fathers father is Rh AB negative

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    • Hi Debbie,

      Yes, it is possible for one parent to be B+, the other to be A+ and their child to be A+.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  109. Alex

    Is it possible to have a child blood type ab+ if a mother is a+ and the father is o+?

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    • Alex,

      Our current understanding of genetics is that it is not possible for one parent to be AB+, the other parent A+ and a child that is O+. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought to be.

      If the question is paternity, the only way to accurately determine who the father is, is with a DNA test. Here’s one example of a DNA test you can get online and administer in your own home. The results are mailed back to you as well.

      I hope that’s helpful.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  110. Ma. Victoria Legaspi

    Me and my husband have AB+, we have 3 children, the first two have type AB+ while our last daughter have A+. Is this really happens.

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    • Yes, it is possible for two AB+ parents to a child who is AB+ and a child who is A+. They can also have a child who is AB-, A-, B+ and B-.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  111. Ziyan

    My mother is A+ and my father is B+ is it possible that me and my brother can be O+?

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    • Ziyan,

      Yes, it is possible for an A+ parent and a B+ parent to have children who are O+.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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      • Ziyan

        Thank you

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      • Ziyan

        Could you explain how this works?

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        • Hi Ziyan,
          A+, B+ O+

          Blood types are comprised of two alleles. The most common (by far) are A, B, and O. Each person also has two Rh alleles that can be positive (+) or negative (-).

          If a person has type A+ blood he or she has at least one A allele (this can be AA or AO) and at least one Rh+ allele (this can be ++ or + -).

          If a person has type B+ blood he or she has at least one B allele (this can be BB or BO) and at least one Rh+ allele (this can be ++ or + -).

          If a person has type O+ blood he or she has two O allele (OO) and at least one Rh+ allele (this can be ++ or + -).

          In the example you provide, both parents would have to have an O allele and they would both pass that down to their child and at least one of them would pass down a + allele. The child would be O (OO) + (+ + or + -).

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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  112. Olivia

    My mom has A- and my dad has B+ blood types. Based on that, what could my blood type be?

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    • Oliva,

      If your mum has A- blood and your dad has B+ blood, you can have A+, A-, B+, B-, O+, O-, AB+ or AB-. Basically, this is one of the few parental combinations that doesn’t rule out any possible outcome.

      Let me know if you’d like to know why.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  113. Anthony

    What blood types are needed for my kids not to have type O ?

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    • Anthony,

      If one parent is AB, the children can not be type O. Other than that, all combinations an result in a type O child.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

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  114. seeker20

    Hi Doc,

    My wife just give birth and my baby is blood type is B+
    my partner and i were ’bout type O is the baby is mine?

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    • Seeker,

      Our current understanding of science is that it is not possible for two O+ parents to have a child that is B+. Two O+ parents can only have children who are O+ or O-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought to be.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  115. WLaett

    I don’t really remember my blood type though I do remember that it wasn’t O. It was Either A or B, not AB if I recall, and I think + though I’m not sure (I last donated blood on 9/11/2001).
    I’m thinking it was either B+ or B- though again I can’t be certain after this long.

    My mother got our genes mapped at 23andme and aside from something we already suspected turning out to be true (we have some east asian heritage on the Estonian side), it also turns out she is of the very rare Diego (Di(a+b+)) blood group.

    What I am dying to know – mainly because it may have health implications if I need a transfusion at any point – is how a rare NON ABO blood group is inherited. What I mean more specifically is…since my mother is Di(a+b+), is it a 50/50 chance that I am as well? Or do mothers just pass that down to their son either way?

    I assume my father was not diego (a+b+) primarily because…well…it is exceedingly rare – something like less than 0.01% of Europeans and Africans have it, and it is mainly diagnostic of having east asian / mongolian heritage (Native Americans would fall under this category as they ultimately originated there was well). It is anomalously high in polish populations and his mother’s side was from Poland and the Baltics and Russia, so I suppose the odds of him having it are quite a lot higher than for western Europeans (though is father’s side is French) where it is seemingly non-existent unless the person has at least some asian or native heritage. But even in Poland – highest % in Europe – it is less than 0.5% of the population. So still incredibly unlikely that he had it (and he’s dead so I can’t get him tested now).

    Given all of that…I am GUESSING it is a 50/50 chance that I am also Di(a+b+) unless my father also was (not bloody likely unless the native rumors on his side were true which I sincerely doubt aside from his grandfather being fairly dark skinned and black haired) – is this the case? Or is it, again, just something that is maternally passed down unlock the main ABO blood groups?

    I wonder if all the immuno skin problems I had when I was young and that my nephew has at the same age in the same places might be related to that. I even wonder if my younger sister dying of SIDS might be related to some reaction between mother and child due to different blood groups.

    I guess it isn’t likely anyone will know because I have searched the net far and wide and all anyone ever talks about is inheriting A, B, AB, or O and never the rare blood groups.

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  116. Alex

    Can O types have kids

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    • Alex,

      There is no reason based on blood type that a mother with type O blood and a father with type O blood can not have children.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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    • Veronica

      I’m O+ and I can kids

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  117. Kurdo

    my blood is A+ and my blood wife is A+ ..what the type is my child will build is possible or best ?

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    • Kurdo,

      If both parents are A+, they can have children who are A+, A-, O+ or O-. None of these blood types cause health issues.

      If the child is female and A- or O-, she will need to alert her doctor before she has children, but that is very far in the future and if there is a medical attention before pregnancy, no issues to her health or her children’s health based on blood type.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  118. Brenda

    My blood type is B don’t know if positive or negative and husband is O and same dont know if positive or negative but daughter came out AB+ how is this possible

    Added:
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    • Hi Brenda,

      Our current understanding of genetics is that it is not possible for one parent to have type B blood, the other parent to have type O blood and a child that is type AB+ or AB-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  119. Downtown97

    I am O negative, my mom is A positive. What blood type does my dad have or could have then, since he does not know what his blood type is?

    Added:
    Reply
    • Hello,

      If you are O- and your mom is A+, your father could be A+, A-, B+, B-, O+ or O-. He could not be AB+ or AB-.

      Hope that helps,

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  120. Sleepless in Sin City.

    My daughters blood type is AB my wife and my own is O+ is this possible? According to what I’ve been told and lead to believe it’s a rare thing that could be brought on by her grandparents. At least this is what her Mother and the nurse at the hospital were saying.

    Added:
    Reply
    • Dear Sleepless,

      Our current understanding of science is that it is not possible for two O+ parents to have a child that is AB+ or AB-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  121. Tyler

    My mom is +A and dad +O what am I?

    Added:
    Reply
    • Tyler,

      If your mom is A+ and you are O+, your father could be A+ or A-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  122. suresh

    I am one child father. My blood group is O- and my B+ can we plan second baby. He/she live perfect life.

    Added:
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    • Suresh,

      I think there is a word missing from your question. Is B+ the blood group of your partner?

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  123. Thea

    Iam 0- blood type and the father is 0. Our daughter is A.
    How could this be?

    Added:
    Reply
    • Thea,

      Our current understanding of genetics is that it is not possible for two parents with O type blood to have a child that is type A. If one of the parents is type A or AB, is would be possible, but two O type parents can only have children with O blood type.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  124. aju

    My wife blood group ab+
    I am o+ my baby boy b+
    This was corect?

    Added:
    Reply
    • Aju,

      Yes, it is possible for one parent to be type AB+, the other to be O+ and the baby to be B+.

      If you’d like an explanation, please let me know.

      Our current understanding of science is that it is not possible for one parent to be AB-, the other parent O+ and a child that is O-. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  125. dianne

    its posibble when my mother is blood type B and my father is blood type O but i am blood type A+?

    Added:
    Reply
    • Dianne,

      Our current understanding of science is that it is not possible for one parent to be B, the other parent O+and a child that is type A.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
      • Manda

        Ok I’m A+ and the dad is B+
        Are son is O- is he the dad ?

        Added:
        Reply
        • Hi Manda,

          If one parent is A+ and the other is B+, it is possible that they can have a child who is O-. Some blood types rule out a potential father, but blood types never determine a specific man as the father. For that you need to do a DNA paternity test. They are 99.999% accurate. Here is an example of one DNA test kit that you could use at home and mail into the lab. The results are mailed back to you as well.

          I hope that’s helpful,

          Best,
          @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

          Added:
          Reply
  126. Huwetah

    Hi I do not know my bloodtyoe but my mom is ab+ and my dad is o- what is my blood type

    Added:
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    • Huwetah,

      If you mom is AB+ and your dad is O-, you could be A+, A-, B+, or B-.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  127. Brittney smith

    My babys blood type is b+ me and who I thought was her father has o+ blood is he actually the father or not? Nowtheres a mother guy and he has b+…. Could he be her father instead of who I thought was

    Added:
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    • Brittney,

      Our current understanding of science is that it is not possible for two O+ parents to have a child that is B+. It is possible for one O+ and one B+ parent to have a child that is B+.

      To determine paternity, a DNA test is 99.999% accurate. You can order them online, take the test in the privacy of your own home, mail in the tests and receive the results by mail. Here is a link to one test you can order online, but there are many options.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  128. Kimberly

    I was just looking at my fathers blood donor card. It says his blood is AB-. My blood type on my donor card says I’m 0+. Does this mean he is not my father? I’m not aware of my mothers blood type not that I think it matters for this question.

    Added:
    Reply
    • Kimberly,

      Our current understanding of science is that it is not possible for a parent who is AB- to have a child who is O+. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought to be.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  129. Christy

    My mother is B+ and my father is O+. My brother is O+ as well but I’m O- is this possible?

    Added:
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    • Christy,

      Yes, it is possible for one parent to be B+, the other to be O+, and their children to be O+ or O-. They could also have children who are B+ or B-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  130. Casey

    I just had a baby the babies blood is o+. The mother’s is o+ and the fathers is o-. Is that possible?

    Added:
    Reply
    • Hi Casey,

      Yes, it is possible for one parent to be O+, the other parent to be O- and their child to be O+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  131. Robyn McCracken

    Can an O+ parent, and an O- parent make an A+ child?

    Added:
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    • Robyn,

      Our current understanding of science is that it is not possible for one parent to be O+, the other parent O- and a child that is A+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  132. Brittney

    If one of my parents are A- and he other is AB+, is it possible for me to be AB-?

    Added:
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    • Brittney,

      Yes, it is possible for one parent to be A-, the other to be AB+ and the child to be AB-. If you’d like an explanation, let me know.

      Our current understanding of science is that it is not possible for one parent to be AB-, the other parent O+ and a child that is O-. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  133. Olivia

    Hello, i am Olivia and my mother and father are both O. I am giving blood soon and I need to know my blood type. What would it be?

    Added:
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    • Oliva,

      When you give blood, they will test your blood type, but if both your parents are type O, you will also be type O.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  134. Anthony

    Hello, I am the father with a blood type of O – , The mother is AB+… our child came out with A+. is this correct? I am the father? or I’m letting people get to my head?

    Added:
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    • Anthony,

      Yes, it is possible for a father to be O-, a mother to be AB+, and their child to be A+.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
      • RAMESH

        if farhera blood group is B positive and morher also B Positive the blood group of the children will be

        Added:
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        • Hello Ramesh,

          If one parent’s blood group is B+ and the other is also B+, each of their children can be B+, B-, O+ or O-.

          Let me know if you’d like an explanation.

          Best,
          @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

          Added:
          Reply
      • denise

        Is it possible for to parents to be o- and have a child with b+

        Added:
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        • Denise,

          Our current understanding of genetics is that it is not possible for both parents to be O- and their child to be B+. Two O- parents can only have a child who is O-.

          It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

          @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

          Added:
          Reply
  135. Brittney

    Hello, my blood type is a+. What are the possibilities of my parents blood type.

    Added:
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    • Brittney,

      If you are A+, at least one of your parents is type A or AB. The other could be O, A, B or AB.

      If you are Rh+, at least one of your parents has to be Rh+, the other could be Rh+ or Rh-.

      I hope that helps,

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  136. T'Shawn Dennis

    Hello, my mothers O- and my father is supposedly AB+ what is the possible result

    Added:
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    • T’Shawn,

      If one parent is O- and the other is AB+, each of their children can be A+, A-, B+ or B-. Their children can not be AB+, AB-, O+ or O-.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  137. Alyssa

    So my child and I are A- The Dr’s said, but the Father is positive blood. So what does that necessarily mean? Does that mean that he isn’t the child’s Father?

    Added:
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    • Alyssa,

      No, that does not mean he is not the child’s father. If a child is -, both of his parents can be either – or +.

      The only way to determine the child’s paternity is a DNA test. They are fairly inexpensive now, you can order them online, do the test in the privacy of your own home, mail them in and receive the results by mail. They are 99.999% accurate.

      Hope that helps, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  138. Chris

    Dear DrGreene,

    How accurate is the blood test for determining the father of the child.

    My brother has type 0 and the woman has type 0 at the same time and the child is type b, is that possible?

    Awaiting your positive response.

    Thanks
    Chris

    Added:
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    • Chris,

      Our current understanding of science is that it is not possible for two type O parents to have a child with type B blood, but blood tests are not considered accurate for paternity.

      If there is a question, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  139. Mohan Natekar

    Hello Doc,

    My blood group is 0+ve and my wife blood group is 0 +ve so what could my baby’s blood group ?

    Thanks & Regards,
    Mohan Natekar

    Added:
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    • Hi Mohan,

      If both parents’ blood is O+, each of their children can be O+ or O-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
    • Eddy

      Hello Doctor, My Girlfriend claims she is O blood group and are both parents are AB, is that possible? Is that possible, she’s getting mad

      Added:
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      • Eddy,

        I don’t understand your question. Are you saying that both of your girlfriends parents are AB and she is O?

        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
        Reply
  140. Krystal

    Hello. My blood type is A+ and my father’s is O+. What would my mom’s blood type be?

    Added:
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    • Krystal,

      If your father’s blood type is O+ and if your blood type is A+, your mother would have to be A+ or A-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  141. Faiz

    Hi doc,
    My blood is “A+” and my wife blood is “AB” Is it correct my son can’t “O” category?

    Added:
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    • Faiz,

      Our current understanding of science is that it is not possible for one parent to be AB, the other parent A+ and their cild to be O. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood types retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  142. ellaine

    Hello, my blood type is B. My parents are both type O. And my 3 siblings are also type O. I already retested my blood many times but it’s really type B. Does it mean that i’m not real daughter of my parents?

    thanks

    Added:
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    • Ellaine,

      Our current understanding of science is that it is not possible for two parents with type O blood to have a child that is type B.

      Though you have retested your blood, have you confirmed your parents’ are indeed both type O? It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
      • ellaine

        yes they are both type O. I already checked their medical records.

        Added:
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        • Ellaine,

          Have you talked with them about your fears? If not, this would be a good time. They may have news for you or they may have another explanation, such as their medical records have been updated with corrected information. Either way, if this is troubling you, it’s time to ask. If you wait until they are gone, you won’t have the opportunity.

          Best,
          @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

          Added:
          Reply
  143. Vee

    My dad’s a O and im a B+ is it possible????

    Added:
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    • Hi Vee,

      If your mom is either B or AB, your dad could be O and you could be B.

      Hope that helps, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
      • Julie

        If my ex wife is ay+ and I’m o- what should my kids be cause all my kids are different blood groups I’m asking of behalf of someone

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  144. Susie Gresham

    Hi, Is it possible for a Rh- parent and a O positive parent to have a A positive child?

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    • Susie,

      An Rh- parent and an O+ parent can have an Rh+ or an Rh- child. One of them must be type A or AB for the child to be type A.

      Best,
      MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  145. J

    Hello, 1. If a Mother is A+ & father AB-…..can one child a son be A+ & a daughter be AB- what are chances or percentages that being? 2. Does it also do with what the Grandparents blood types are in the chances or percentages?

    Added:
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    • J,

      If a mother is A+ and a father is AB-:
      There is a 50% chance each child will be type A
      There is a 37.5% chance each child will be type AB
      There is a 75% chance each child will be Rh+
      There is a 25% chance each child will be Rh-

      I don’t believe the grandparents blood types change the percentages. If someone reading this has more information, please pipe up.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
      • J

        Thank you for your reply…I see & know the %’s.. I also checked on site that had calculator…but on one site I looked up & it calcaluted.. if a father is AB – & child is AB- then mother had to be a – ..this was confusing. With the % you gave & I looked up on another site??? I don’t under stand why different??Can you Explain? The AB- child daughter what probability would she be on DNA cheek swab test Or what probility would she be as child to the father on a DNA Cheek swab test done in a County Attorney office or legal setting?..or any help appreciate? all Thank you so much!

        Added:
        Reply
        • J,

          I can’t tell you what a DNA test will show based on blood types. No one can. Sorry.

          Best,
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

          Added:
          Reply
  146. Job Murphy

    I’m AB+ and my girl friend is O+ and our baby girl is AB + is that possible?

    Added:
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    • Job,

      Our current understanding of science is that it is not possible for one parent to be AB+, the other parent O+ and a child to be AB+. An O parent can can not have an AB child.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      Reply
  147. Zainab

    Madam,if we both siblings are A+ that is blood group of my mother whereas my father is O-,
    Is it confirmed that my mother homozygous is rh+?

    Added:
    Reply
    • Zainab,

      If your father is O- and your mother is Rh+, and you and your siblings are A+, your mother would be A+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  148. Marie

    My husband is O pos, I am AB neg. With both pregnancies I had to have the RH shot. My daughter is B pos. Is this normal and is there any reason to suspect that my daughter isn’t my husband’s child?

    Added:
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    • Marie,

      In the scenario you suggested, it is very possible for the mother to be AB-, the father to be O+ and the child to be B+.

      However, I can not tell you if he is the father or not. Blood types can not determine paternity, but they can rule out some potential men as the father. In this case, he is not ruled out.

      I hope that’s helpful.
      @MsGreene

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  149. jeanne

    HI, I’m sorry if this question has already been covered but I couldn’t seem to find my exact scenario & wanted to be sure I understood correctly. My father was O+. My mother always said she thought she was B+ but I saw some paperwork saying she was A+. I have A- blood. Could this be possible. When my son needed blood (also A-) I was the only one in my family who could give as no one else matched. What blood types could be possible in this situation? Thanks so much for your help.

    Added:
    Reply
    • Jeanne,

      If your father is O+ and you are A-, your mother could be A+, A-, AB+ or AB-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  150. Dhee

    Hi I’m wondering my blood type is B+ and i want to know what is my child possible blood type. Thank you

    Added:
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    • Dhee,

      Your child’s blood type is determined by both parents blood types, so it’s hard to say without knowing your partner’s blood type. But will pass along half the code for your child and that will be either B+, B-, O+ or O-. If your partner is A or AB, that opens up A+, A-, AB+ and AB-.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
    • Dhee

      Hi again my two sisters are both A+ and I’m B+ does it means our parents blood types are AB+? Thank you

      Added:
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      • Dhee,

        If three siblings are blood types A+ and B+:
        At least one parent has to be RH+. The other can be R+ or Rh-.
        One parent has to pass down an A AND the other has to pass down a B.
        One parent could be AB+, if the other parent is O+ or O-.
        One parent could be AB-, if the other parent is O+.
        One parent could be A+ or A-, if the other parent is B+.
        One parent could be B+ or B-, if the other parent is A+.

        I hope that’s helpful.

        Best, @MsGreene
        Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  151. Dina

    Hi docter,

    Im rh- and the father of my baby is 0+ what blood group could my baby be

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    • Dina,

      From what you’ve told me, your baby could be Rh+ or Rh-.

      Is your blood type O-, A-, B- or AB-? Without knowing that, I can only tell you, if the father of your baby is O+ and you are Rh-, your baby could be O+ or O-. But this is very incomplete.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  152. Gen

    Hellow Dr. My blood type is A positive , my fathers blood type is O, my mothers blood type is B positive, my brother and sisters have the blood types B positive and O, Why is it that it is only I who has the A positive blood? What do this one tell?

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    • Gen,

      Our current understanding of genetics is that it is not possible for one parent to be B+, the other parent O and a child that is A+. If one parent is B and the other is O, they can have children who are B and O. One of the parents must have type A or AB blood for the child to be type A.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  153. rohit

    My blood group is O positive and my wife blood group is B positive; Is it possible that my baby have blood group A positive.

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    • Rohit,

      Our current understanding of genetics is that it is not possible for one parent to be O+, the other parent B+ and a child that is A+. One of the parents must have type A blood to pass down to the child.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  154. jessica

    hello. my dad is O- and my mum is O+. i’m guessing i’m an O. but what Rh am i?

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    • Jessica,

      If your dad is O- and your mum is O+ you could be O+ or O-. You would have to be tested to be sure, but O+ is more common than O-.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  155. Alyssa White

    I’m O+ and my daughter is O+ so what could her father’s blood type be?

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    • Hi Alyssa,

      If you are O+ and your daughter is O+, her father could be O+, O-, A+, A-, B+, or B-. He could not be AB+ or AB-.

      If you’d like and explanation, please let me know.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  156. Rachel G.

    My father is type O, but my mother is RH negative. Both of my siblings and both of my children are type O.
    I somehow came out as A positive.
    I’d like to learn why it is that I am A positive, but the only explanation I’ve gotten is “its complicated” from my GP.
    Could you please explain this to me and/or direct me to an easy to understand resource that can?
    Thank you

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    • Rachel,

      Blood types are comprised of two alleles for the “letter type” and two different alleles for the “Rh type”. Each person gets one letter allele and one Rh allele from each parent.

      The most common letters (by far) are A, B, and O. Here is how that looks:
      Type A = AA or AO
      Type B = BB or BO
      Type O = OO
      Type AB = AB

      Each person also has two Rh alleles.
      Rh+ = two + alleles (+ +) OR one + and one – (+ -)
      Rh- = two Rh- alleles (- -)

      In the example you provide, one parent is O, but you don’t state if he is Rh+ or Rh-. If he is O+ he can only pass down an O allele. He if is Rh+ he can pass down either a + or a – allele. If he is Rh- he can only pass down a – allele.

      You state your mother is Rh-, so she could only pass down a – allele, but we don’t know what her letter type is. If she is A+ or A-, she could pass down the A, but only a negative allele.

      You don’t really have enough information to make a good case, but that’s one example of how it could have happened.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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      • Flavia

        I’m A POSITIVE with Rh negative and the baby came out o positive.. what blood type does his father has?

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        • Flavia,

          The POSITIVE part of the blood type is Rh, so you’re either A Rh+ or A Rh-, which are called A+ or A-. You can’t be both.

          If you are A+, and your baby is O+, the father could be A+, A-, O+, O-, B+, or B-, but not AB+ or AB-.

          If you are A-, and your baby is O+, the father could be A+, O+, or B+, but not A-, O-, B-, AB+ or AB-.

          Hope that helps, @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  157. Danica B. Goayan

    Doc I just want to ask, is it true that its hard to conceive if both are type AB? Because in my case Doc my husband is Type AB and me also is type AB. Way back 2014 Doc I got pregnant but I suffered Miscarriage that time I’m 2 months pregnant, until now Doc were really trying to conceive. Does it affects Doc that we both have the same Blood Type?

    Hoping for your response Doc, thank you so much

    Danica

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    • Danica,

      I don’t know of any research that shows it’s harder to conceive if both mother and father have the same blood type. Does anyone else here have research that would show this has any impact?

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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      Reply
  158. Shelbyy Johnston

    I have O- and my spouse has A+ was curious on what the possible blood types for my children could be

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    • Shelbyy,

      If you are O- and your partner is A+, each of your children could be O+, O-, A+ or A-.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      Reply
  159. Caitlin Robertson

    Hi,
    My dad is AB- and my mum is o+ how is it possible for me and my siblings to have o-blood? and yes a DNA test has been completed we are his kids.

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    • Caitlin,

      According to our current understanding of genetics, this isn’t possible.

      DNA paternity tests are 99.999% accurate, so I would accept those results. Are you sure all the blood types are accurate?

      If the blood tests are accurate and the DNA tests are accurate, this is a genuine anomaly.

      Best, @MsGreene
      Note: I reply to a lot of the comments on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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      Reply
  160. Marie

    I’m O positive and my husband said he was A positive. We have a baby girl who is A positive and just found out that our twins girls who are 2 & 1/2 are AB positive. I’m confused. Is that possible or would he have to be AB positive? Thank you.

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    • Marie,

      Our current understanding of science is an O parent can not have a child who is AB.

      It is not uncommon for blood types to be different than they are remembered. It would be wise to have all your blood types retested.

      Best, @MsGreene
      Note: I reply to a lot of the comments on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  161. Linus

    Can both parents that have the same blood type A+ give birth to what group of a child?

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    • Linus,

      If both parents are blood type A+, each of their children can be A+, A-, O+ or O-.

      If you’d like an explanation, let me know.

      Best, @MsGreene
      Note: I reply to a lot of the comments on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
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  162. Ajith

    I’m B+ve,my father O+ve and my mothers B-ve. If i marry which blood group is needed for a baby boy

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    • Ajith,

      Our current understanding of genetics is there is not a link between parents blood group and the gender of their child.

      Consider this — most parents don’t have all boys or all girls. If blood group determined the gender, then all the children would be the same.

      Best,
      @MsGreene

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  163. Krishna

    Hi doctor this is Krishna mine is O positive my wife is A negative my child is boy or girl and what blood group he/she have?

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    • Krishna,

      I can not tell you whether your child will be a boy or girl. If I could do that, I would be very famous :)

      I can tell you that if your blood type is O+ and your wife’s is A-, each of your children could be O+, O-, A+ or A-.

      There is one additional concern — when the mother’s blood type is Rh- and the father’s is Rh+, there can be a blood type incompatibility. Dr. Greene has written extensively about it in this post — How To Determine and Manage Rh Incompatibility.

      Best,
      @MsGreene

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  164. Carla

    Hello I had a question I am a little confused about.
    I am o+ and all three of my sons are a+.
    I am wondering what their fathers blood type could be?
    Also, I’m confused as to why exactly were my three sons bilirubin higher than normal at birth, I know it has something to do with blood type or something but I’m just a tad confused. My dr tried explaining but I didn’t understand. Thank you.

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  165. carolnina

    the mother is AB and the father is O how come that the baby is type O and now has a sepsis

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    • Carolnina,

      Our current understanding of science is that it is not possible for one parent to be AB, the other parent O and a child that is O. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      I doubt that the sepsis is related to the blood type. There can be, however, a blood issue if the mother is Rh-, the father is Rh+ and the baby is Rh+.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  166. Lavina

    My mother is O and father is B and I am B+. I don’t know if either have a – or + ? Would that matter? My sister is AB+ that does not make sense to me.

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    • Lavina,

      According to our current understanding of genetics, if a child is AB, his or her mother can not be O.

      The most likely cause for this discrepancy is one of the blood types is different than thought. It is not unusual for there to be an error in the test, an error in reporting, or an incorrect memory of one or more of the blood types. It would be wise to have both types retested.

      Best,
      @MsGreene

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  167. lou

    Hi Dr,

    My daughter had our first grandchild yesterday morning, Father is O and She is O baby boy is A, that seems impossible if i understand your chart? But she is not the cheating type so we are all in shock….what are other possibilities if any?

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    • Iou,

      You are correct. This is considered an impossible outcome.

      The most likely situation is one of the three blood types is not what you think it is. This if far more common that you would guess. Either one of the tests had an error, or was recorded inaccurately, or simply remembered differently than it is.

      If there remains a discrepancy after re-testing, the best way to know for sure is DNA paternity testing, which is 99.999% accurate.

      Best,
      @MsGreene

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  168. Hatton

    I am A+ n my ex is A+ but our daughter is O- does that mean he’s not her daddy?

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    • Hatton,

      Not necessarily.

      Blood types are determined by two alleles – one from each parent:
      1) People who have type A+ blood can either have two A alleles (AA) or one A and one O (AO). Both are called type A.
      2) People who are Rh+ can either have two + alleles (++) or one + and one – (+-).
      3) In your situation, both parents could be AO and each one passed down the O allele, so the baby is O.
      4) Each parent could also be +- and pass down the – allele, so the baby is Rh-.

      That also doesn’t proved your ex is the father. Simply that he could be. DNA paternity testing is the only way to be sure. It’s 99.999% accurate.

      Does that make sense?

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      • denise

        Is it possible that two parents have a child that is B possible

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  169. shamira

    Hi Doctor, I am A- and my husband is 0+ what could our child be?

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    • Shamira,

      If you are type A- and your husband is type O+, each of your children could be O+, O-, A+ or A-.

      Let me know if you’d like an explanation.

      @MsGreene

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      • shamira

        Thank you

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  170. Merrith

    If I am RH 0- and my mom was a- what would my father be?

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    • Merrith,

      If you are O- and your mom was A-, your father could be O+, O-, A+, A-, B+, or B-. He could not be AB+ or AB-.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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  171. Sherry horwath

    Is it possible for a child to have AB positive if one parent is AB positive and the other is o positive?

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    • Sherry,

      Our current understanding of science is that it is not possible for one parent to be AB+, the other parent O+ and a child to be AB+. If one parent is AB and the other parent is A, B or AB, it is possible.

      In a situation like this, it is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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      • Mher Diosomito

        Hi my husband is o+ and me is ab what was the baby s blood type

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        • Mher,

          If one parent is AB and the other is O+, each of their children will be either A+, A-, B+ or B-.

          If you’d like an explanation, let me know.

          Best,
          @MsGreene

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  172. Lim

    Ok Noted. But based on this website endmemo.com there is 75% more for an type A or B passed down to him/her child, am i correct and only 25% for blood type O.

    So could there highly be chances she could mostly have the same..?? You also stated that it’s most common blood types in the world

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  173. Margaret

    If im an b+ and my daughter is an a+ what would her dad be

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    • Margaret,

      If you are B+ and your daughter is A+, her father would have to be A+ or A-.

      If you’d like an explanation, let me know.

      @MsGreene

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  174. Lim

    Dear Dr.Greene,

    My dad is O+… My blood type is also the same. I’m not sure what my Mum blood is as my parents are seperated..

    What is the likelihood of my Mum blood type is? Does she also happen to be O+/O-? Btw, im asian..

    Hope to hear from you soon. Thank you

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    • Lim,

      Type O blood is the most common type, but a parent does not have to be type O to pass that down to her child. In fact the only blood type that can not pass down O is AB. If you are O+, and your father is O+ your mother could be O+, O-, A+, A-, B+ or B-.

      The only way to know for sure, is to have her blood tested.

      @MsGreene

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  175. Clare

    Hi my blood type is b neg and daughter is 0 negative what is the fathers blood type please?

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    • Clare,

      If your blood type is B- and your daughter’s blood type is O-, her father’s blood type could be O+, O-, B+, B-, A+, A-, but can not be AB+ or AB-.

      I hope that’s helpful,
      @MsGreene

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  176. Debbie

    My blood type is AB Neg and my husband is O negative. What would my son be? A or B?

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    • Debbie,

      If one parent is AB- and the other is O-, each of their children could be A- or B-.

      Best,
      @MsGreene

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  177. Payal

    My blood group is AB+ and my husband’s O+. What are the possible blood group that my child may born with?

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    • Payal,

      If one parent’s blood group is AB+ and the other is O+, each of their children could be A+, A-, B+ or B-.

      Let me know if you’d like an explanation.

      @MsGreene

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  178. Priya

    My blood group is o positive and my husband blood group is AB negative my son bloody group ?

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    • Priya,

      If your blood is O+ and your husband’s is AB-, each of your children can be A+, A-, B+, or B-.

      Best,
      @MsGreene

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  179. Alvaron Alexander

    I am A+ female and my significant other is B- male. Is it possible for us conceive and have a healthy child?

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    • Alvaron,

      There is no reason based on your blood types that you can not have a healthy child. The issue with blood type incompatibility is if the female is RH- and the male is Rh+.

      Best,
      @MsGreene

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  180. Shawntee

    I’m O+ and my daughter is A+. What would her dad’s blood type have to be to make her A+?

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    • Shawntee,

      If your blood type is O+ and your daughter’s is A+, her father would have to be A+ or A-.

      Best,
      @MsGreene

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    • Arthur Jones

      My daughter is A+ so I want to know what will I be.

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      • Arthur,

        Do you know your daughter’s mother’s blood type? Without knowing that, no blood types are eliminated.

        Best,
        @MsGreene

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  181. Jamie

    My blood type is O-. My daughter is B-. My son is O-.
    What would my husband be?

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    • Jamie,

      If your blood type is O- and you have one child who is B- and one who is O-, and they have the same father, he would be B+ or B-.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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  182. Jacky

    Hi

    I’m O+ and my husband is A-, my children are all O-
    my child would like to know why her blood type is O- and not A+

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    • Hi Jacky,

      Each person’s blood type is determined by two alleles for A, B or O and two alleles for Rh+ or Rh-. Each person get one blood type allele and one Rh allele from each parent.

      If a parent is O+, he or she has two O alleles (OO) and can have two + alleles (+ +) or one + and one – (+ -). That parent can only pass down an O, but can pass down either a + or a – allele to each child.

      If a parent is A-, he or she can have two A alleles (AA) or one A and one O (AO), but can only have two – negative alleles (- -). That parent can pass down an A or an O allele, and can only pass down a – allele to each child.

      In the example you outlined, The child with O- blood received O alleles from each parent, and – alleles from each parent.

      Does this make sense?

      Best,
      @MsGreene

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  183. norda

    if a mother is O neg and father is O pos can the daughter be A neg?

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    • Norda,

      Our current understanding of science is that it is not possible for one parent to be O-, the other parent O+ and a child that is A-. Two type O parents can only have type O children.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  184. DB

    If one parent is O RH negative, and the other parent is O RH positive, is it possible to have a baby A RH negative?

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    • DB,

      Our current understanding of science is that it is not possible for one parent to be O-, the other parent O+ and a child that is A-. For a child to have type A blood, one parent needs to be type A or AB.

      It would be wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      Best,

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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      • DB

        Recently I found a card from the hospital I was born at with my parents, siblings, and my blood type (when I was born and registered). I’m the only one w A-. My mother swears she never had an affair. The only other possibility is I may have been switched at birth. And suggestions on how I go about researching this?

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        • DB

          I had my blood tested, and the records were incorrect in 1970. I am O negative. Thank you Doctor

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          • DB,

            I’m very glad you were able to resolve this seeming inconsistency. I would love for you to comment to other folks here who are worried because their blood types appear to be “impossible”. It is so common for records to be incorrect.

            Best,
            @MsGreene

            Added:
        • DB,

          Old records are sometimes in error. Before drawing a conclusion, it is wise to have your blood and your parents’ blood retested. Better yet, you can do a DNA paternity test (for about $99, with testing at home then sent to a lab) that is 99.999% accurate. This would require your father’s cooperation.

          Best,
          @MsGreene

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        • Teresa

          Teresa
          Dr. Green,
          If a mother has the blood type O negative and the father is A positive, what could their children be? A negative?
          Thank you!

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          • Hi Teresa,

            If one parent is O- and the other is A+, each of their children can be O+, O-, A+ or A-.

            Best, @MsGreene
            Co-founder & Executive Producer DrGreene.com, Mom
            Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

            Added:
  185. Augustine

    Hi Dr, my daughter was recently sick and needed blood. My wife and I volunterred to donate our blood but to our surprise both of us could not because ours didn’t March with hers. Is there a possibility for that?

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  186. SHANOJ

    Sir
    My Blood Group AB+ and my Wife Blood group B+, My child what are the blood group.

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    • Shanoj,

      If one parent is AB+ and the other is B+, each of their children could be AB+, AB-, A+, A-, B+ or B-. None of their children can be O+ or O-.

      Best,
      @MsGreene

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    • SHANOJ

      possible o+

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      • Shanoj,

        If both parents are O+, each of their children will be O+ or O-.

        Best,
        @MsGreene

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  187. Joy

    My blood group & my wife’s blood group is same.. Will it take any effect on our upcoming 1st children ??

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    • Joy,

      Parents blood type determines their child’s blood type, but they will not necessarily be the same. What are your blood types?

      Best,
      @MsGreene

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      • BABUU

        My blood group is 0+ve and my partner is 0+ve…what will be our child blood group be??
        I pleas to here from you.

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        • Babuu,

          If you and your partner are both O+ each of your children could be O+ or O-.

          Let me know if you’d like an explanation.

          Best, @MsGreene
          Note: I reply to a lot of the comments on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  188. Tony

    My partner is o negative i am o positive is these blood group compatible

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  189. Tania Rodgers

    Hi. Im an o- and both my daughters are o-. Not sure of my sons but being 2 negatives make a negative can i assume my husband is a negative as well as both my boys?

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    • Tania,

      No, that is not how it works. Rh factor is determined by two alleles that are either – or +. A child gets one from each parent.

      If a person is called Rh- he or she has two negative (-) alleles.
      If a person is called Rh+, he or she either has two + alleles or one + and one -. That means a person who is RH+ can pass down a – allele. In other words, your husband could be Rh+ and pass down an – allele to your daughters, but not necessarily to your sons.

      Does that makes sense?

      @MsGreene

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      • Tania Rodgers

        Thank-you yes that makes sense.

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  190. Ashley

    My blood type is o- and the father to my child has o+ blood…So I know our child will have O type blood but if my child is born with o- negative blood will that mean she and I are rh incompatable? or is she is born with o+ blood will her and her father be rh incompatable since he has o+ blood type as well?

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  191. Neethu

    Hello Doctor…

    My husband’s blood gp is O positive, my blood gp is AB positive .we have one male child what are the possible blood gps…

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    Reply
    • Neethu,

      If one parent is O+ and the other is AB+, each of their children could be A+, A-, B+ or B-. They can not be AB or O.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene

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  192. Suzanne

    Hi Dr Greene, I am A+ My 2 children are O- both their fathers are A+. Is that possible?

    Also One of my daughters (O-) has an O + baby.

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    • Suzanne,

      It is possible for two A+ parents to have children that are O-. It is also possible for a parent that is O- to have an O+ child.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  193. Gf

    My blood type is A – and my wife’s is O+.. what would this make our daughters?

    Added:
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    • Dear GF,

      If one parent is A- and the other is O+, each of their children could be A+, A-, O+ or O-.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene

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      • jdc

        i would like an explination

        Added:
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        • Dear JDC,

          You ask “My blood type is A – and my wife’s is O+. what would this make our daughters?”

          1) If a parent is A- he or she can have two A alleles (AA) or one A and one O (AO). If he is Rh-, he has two – (- -).
          2) If a parent is O+ he or she can has two O alleles (OO) and can have two + alleles (+ +), or one + and one negative (+ -).
          3) If the A- parent passes down an A allele and a – allele and the O+ parent passes down an O alleles and a + allele, their child will be AO+-, which we call A+.
          4) If the A- parent passes down an A allele and a – allele and the O+ parent passes down an O alleles and a – allele, their child will be AO- -, which we call A-.
          5) If the A- parent passes down an O alleles and a – and the O+ parent passes down an O and a +, their child will be OO+-, which we call O+.
          6) If the A- parent passes down an O alleles and a – and the O+ parent passes down an O and a -, their child will be OO- -, which we call O-.

          Does that make sense?

          Best,
          @MsGreene

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  194. Yeo

    My blood type is B+ and my wife is AB+.

    My child is B-

    Is it possible? What are the chances?

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    • Yeo,

      Yes, it is possible for an AB+ parent and a B+ parent to have a B- child. In terms of odds, there is a 50% chance the child would be type B and a 6.35% chance the child would be Rh-.

      Best,
      @MsGreene

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  195. Jerricka

    My father is B+ and my mother is A+ but im O- and my sister is O+ how is that possible?

    Added:
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    • Hi Jerricka,

      Each person has two alleles that determine blood type and type that determine Rh type. Here is how that looks:
      A = AA or AO
      B = BB or BO
      O = OO
      AB = AB
      Rh+ = + + or + –
      Rh- = – –

      In the example you provide, if the father is BO+-, and the mother is AO+- they could each pass down an O allele so their child would be O (OO). In the case of an O- child they each has to pass down a – allele. In the case of an O+ child at least one of them passed down an + allele.

      I hope that’s helpful,
      @MsGreene

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      • Jerricka

        It is helpful thank you… I have a couple more questions. #1. Both of my kids are A+ (which obviously they received from their fathers) and i had to receive shots so my body wouldnt attack my children and when my blood mixed with my first child i developed antibodies in my blood and can no longer donate plasma because of it but noone ever explained why to me. Can you please explain if you know why i can no longer donate? #2. Would i ever be able to donate blood to family or my children if they ever need it being i have O- blood with antibodies? Would it affect me donating anything other than blood either?

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  196. Lewis Bramhall

    Hi there,

    My partner and I recently had a baby girl. My partners blood type is RH- O- and our childs blood type is RH+ O+. I was wondering if you could determine my blood type with the information of theirs. Just plain curiosity!

    Thanks.

    Added:
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    • Lewis,

      If one parent is O- and the child is O+, the other parent could be O+, A+, or B+.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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  197. Kim davies

    Hi my blood group is A neg and both of my kids are A neg like me but what blood group could my husband be thanks x

    Added:
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    • Kim,

      If one parent is A- and his or her children are A-, the other parent could be A+, A-, B+, B-, O+ or O-, but not AB+ or AB-.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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  198. alison

    If I’m rhesus negative will my child be the same

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    • Hi Alison,

      If a mother is Rh-, but the father is Rh+, the children can be either Rh+ or Rh-. Only if both parents are Rh- is it assured that the children will be Rh-. On the other hand, if both parents are Rh+ their children can be either Rh+ or Rh-.

      Of concern, if the mother is Rh- and the father is Rh+, their may be an Rh incompatibility between the mother and the baby.

      I hope that’s helpful.
      @MsGreene

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  199. Jeevan

    If father blood group A negative and mother blood gruop is A positive. Then child blood gruop is A negative. If possible?? Let me know

    Added:
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    • Hi Jeevan,

      If the father’s blood group is A- and the mother’s blood group is A+, each of their children can be A+, A-, O+ or A-.

      If you’d like an explanation, let me know.

      @MsGreene

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  200. confused

    Hi Dr,I don’t know my blood group, but my husband is O+, my daughter is AB- and my son is AB+, so I concluded that my blood type is AB, is that possible?

    Added:
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    • Confused,

      According to our current understanding of genetics, a parent with type O blood can not have children who are type AB. For children to be type AB, one parent is either A or AB and the other is either B or AB.

      In this situation, it would be wise to have your husband’s blood retested. It is likely different than what you believe it to be.

      Best,
      @MsGreene

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      • Gebru Brhane

        Dr. I am O negative and the mother of my baby is B plus what blood group could my baby be?
        Am waiting your kind response

        Added:
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        • Gebru,

          If you are O- and the mother of your baby is B+, your baby could be O+, O-, B+ or B-.

          If you’d like an explanation, please let me know.

          Best, @MsGreene
          Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

          Added:
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  201. Aria

    If the father is O- can the baby be O+

    Added:
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    • Aria,

      It is possible for a father who is O- to have a baby who is O+, if the mother is Rh+.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene

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  202. Gozie

    I am B+ and my husband is A- and I just tested my son and he’s O+…
    is it possible?

    Added:
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    • Hi Gozie,

      Yes, it is possible for a father who is B+ and a mother who is A- to have a child who is O+. If you’d like an explanation, please let me know.

      Of concern, if the mother is Rh- and the child is Rh+, there may be Rh incompatibility.

      Best,
      @MsGreene

      Added:
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      • Gozie

        thank you so much for responding, but please if it isn’t a bother I need a bit of explanation.
        I the mum is Rh+(B+) and my son is Rh+(O+) but the dad is Rh- (A-).

        Added:
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        • Hi Gozie,

          Each person has two alleles that make up their blood type. The most common (by far) are A, B, and O. Also, each person has two Rh alleles. These are positive or negative.

          If a person is B+, he or she can be BB or BO and + + or + -.
          If a person is A-, he or she can be AA or AO and – -.
          If a person is O+, he or she has two O alleles, OO and can be + + or + -.

          In the scenario you purpose:
          If the mum is B+ (BO) she passed down an O allele and either + or – Rh.
          If the dad is A- (AO) he passed down an O allele and either + or – Rh.
          If the son is O+ he is OO and either + + (if he got + alleles from both parents) or + – (if he got one + allele from on parent and one – allele from the other.

          I hope that makes sense.
          @MsGreene
          If these two people have a child, the first could pass down either

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  203. Kerry

    Hi
    I’m rehues negative my mother is not would my father be the same as me
    Thanks kerry

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    • Hi Kerry,

      If a child is Rh-, his or her parents can still both be Rh+.

      Each person has two Rh alleles that are either + or -. A child gets one from each parent.

      We call someone Rh+ if they are + + or + –
      We call someone Rh- if they are – –

      Based on the above, both parents could be Rh+ (+ -) and each one pass down the Rh- so the child is – – or Rh-.

      Hope that helps,
      @MsGreene

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      • Kerry

        Hi so as my mother is not my dad has to be is that right

        Added:
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        • Hi Kerry,

          There was a typo in my reply to you (so sorry – I know this made it very confusing). I’ve corrected my error. The correct answer is both parent can be Rh+ and have a child who is Rh-. This means if you are Rh-, both parents could be Rh+.

          Again, my apologies.
          @MsGreene

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  204. Curious

    If a mother is a+ and baby is o+ what would the father be?

    Added:
    Reply
    • Curious,

      If a mother is a+ and baby is o+, the father could be A+, A-, B+, B-, O+, or O-. He could not be AB+ or AB-.

      Best,
      @MsGreene

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  205. Shell

    If Im blood type O+ and my daughter is A+ can her fathers blood type be A-

    Added:
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    • Shell,

      Yes, if the mother is O+ and the child is A+ the father can be A-.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  206. Tina

    Hi sorry but both my parents are dead now so can’t ask them. I am o+ and my sister o-, what’s the blood group possibilities of our parents, if we are meant to have the same Father please?

    Added:
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    • Tina,

      If two children are O+ and O-, and they have the same parents, at least one parent must be Rh+, but the other could be Rh+ or Rh-. Their blood groups can be A, B or O, but not AB.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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      Reply
  207. Kelly

    Hi if my mum is A- and my dad is 0+ is it normal to have the baby with 0 blood?

    Added:
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    • Hi Kelly,

      Yes, this is normal.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  208. Amanda

    Just had my baby boy yesterday 10/9 and found out he has O- blood im O + so that will make his father what blood type because my husband doesnt know his just curious to know

    Added:
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    • Hi Amanda,

      Congratulations! What an exciting time for your all.

      If one parent is O+ and the child is O- the other parent can be A+, A-, B+, B-, O+ or O-, but can not be AB+ or AB-.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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      Reply
  209. kool whip

    Can a 0+ and a 0- make an A- baby

    Added:
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    • Kool Whip,

      Our current understanding of genetics is that it is not possible for one parent to be O+, the other parent to be O- and their child to be A-.

      It is not uncommon for at least one person’s blood type to be different than what is thought. It’s wise to have blood types retested before jumping to any conclusions.

      Best,
      @MsGreene

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      Reply
  210. John

    Hi, my bloode type is b+ and my wife is o. Is it possible if my daughter has bloodtype A?

    Added:
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    • John,

      According to our current understanding of genetics, it is not possible for one parent to be B+, the other parent to be O, and their child to be type A.

      Before jumping to any conclusions, it’s wise to have everyone’s blood retested. It’s not uncommon for one or more of the types to be different than what is thought.

      Best,
      @MsGreene

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  211. Jessica

    If me and my son have the same blood type (a-) then does his dad have the same

    Added:
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    • Hi Jessica,

      No, this does not mean your son’s father has the same blood type.

      If you and your son are both A-, his father could be A-, A+, B-, B+ O-, or O+. The father can not be AB- or AB+.

      If you would like more of an explanation, let me know.

      Best,
      @MsGreene

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  212. Rc

    I have AB blood type and my wife is O blood type, is it possible to have a O blood type child? If so can you explain please.

    Regards,

    Added:
    Reply
    • RC,

      According to our current understanding of genetics, it is not possible for a parent with AB blood type to have a child with O blood type. It is possible for a parent with AB blood to have a child with A, B or AB.

      I hope that’s helpful.

      @MsGreene

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  213. Angie Atkinson

    If mother is O+ and father is B- can the child have B+?

    Added:
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    • Angie,

      Yes, if one parent is O+ and the other is B-, they can have a child that is B+.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene

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  214. Jenell

    Hi doc, i have a question if a woman is married for a second time. Her first husband was blood type A and her son by that marriage was type O. Her new husband is type B and their child is type AB. What is the woman’s blood group ? .. Thank you sir for answering.

    Added:
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    • Jenell,

      In the scenario you suggest, the woman’s blood group is A.

      Blood type is comprised of two alleles that we name A, B, O. Type A can be AA or AO, type B can be BB or BO, type O can only be OO.

      Assuming all the blood types you cite are correct:
      – The woman had AO and her first husband had AO. They each passed down the O allele and that child was type O.
      – In her second marriage, the new husband was either BB or BO. He passed down the B and the woman passed down the A so their child was AB.

      I hope that’s helpful,
      @MsGreene

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  215. Gayashi

    Father’s blood group O +,
    baby’s blood group AB +
    Is it correct? Father should O blood group can baby AB. Pls reply it can be happened.

    Thanks

    Added:
    Reply
    • Gayashi,

      According to our current understanding of genetics, a parent with type O blood can not have a child with AB blood.

      Please keep in mind that it is not unusual for blood types to be different than they are thought to be. Before drawing any conclusions, it’s wise to have everyone’s blood type retested.

      Best,
      @MsGreene

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      • pavi

        If the mom had B+ blood group then is it correct ?

        Added:
        Reply
        • Pavi,

          No. If either parent is type O, the child can not be AB.

          Best,
          @MsGreene

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  216. Stephanie Granberry

    father is A+ , mother is B- , first child is O- and second is AB-, how is this possible. Thank you

    Added:
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    • Dear Stephanie,

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O. Each person also has either an Rh+ or Rh- allele.

      If a person has type A+ blood he or she has at least one A allele (this can be AA or AO) and at least one Rh+ allele (this can be ++ or + -).

      If a person has type B- blood he or she has at least one B allele (this can be BB or BO) and two Rh- alleles (- -).

      In the example you provide, if one parents is A+, he or she could be AA or AO, ++ or +-. He or she could each pass down an A or an O allele and a + or a – allele.

      If the other parents is B-, he or she could be BB or BO, and must be – -. He or she could each pass down an B or an O allele and a – allele.

      Each of their children could them be AB+, AB-, A+, A-, B+, B-, O+ or O-. You may have noticed, their an A+ father and a B- mother can have essentially any blood type child.

      I hope this is helpful.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  217. Savannah

    Hi Doc , I have O positive blood and so does my fiance would our baby have + or -?

    Added:
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    • Hi Savannah,

      If both parents have O+ blood, each of their children can be Rh+ or Rh-.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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  218. Michelle

    If I am O- and my son is O- what blood type would the dad have?

    Added:
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    • Michelle,

      If one parent is O- and the child is O-, the other parent could be O- or O+.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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      Reply
  219. Kim

    Hi , if a mothers blood is A+ and the father is o- is it normal for the baby to be A-? I thought the o gene in fathers get passed on to the kid?

    Thanks

    Added:
    Reply
    • Kim,

      Yes, it is normal for one parent’s blood type to be A+, the other to be O- and their child to be A-. They could also have children who are A+, O+ and O-.

      Best,
      @MsGreene

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  220. Ashish

    I have a question..
    If a husband and wife both have B+ blood group then their child will sure have B+ blood group or variation occours??

    Added:
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    • Ashish,

      If both mother and father have B+ blood, each of there children could have B+, B-, O+ or O- blood types.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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      Reply
  221. Kazz

    Hi if the mother is 0+ and the baby A+.. What type would the father have to be?

    Added:
    Reply
    • Kazz,

      If the mother is O+ and the baby is A+ the father would be A+ or A-.

      Best,
      @MsGreene

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      Reply
  222. Crystal

    Hello, I’m b- and the Father is O-.. What would be the blood type of our baby?

    Added:
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    • Crystal,

      If the mother is B- and the father is O-, each of their children could be B- or O-.

      Women with Rh- blood have a risk of blood type incompatibility if their partner has Rh+ blood. The good news for you, is if you are Rh- and the father of your baby is Rh-, there isn’t an issue.

      Best,
      @MsGreene

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  223. Granny

    If the mother and father both have O+ blood could they have a child with O- blood type????

    Added:
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    • Granny,

      Yes, it is completely normal for two parents with O+ blood to have a child with O- blood.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  224. Beth

    Hello,if the mother is o+ and father is o+. Could they have a child with o-?

    Added:
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    • Hi Beth,

      Yes, if both parents have O+ blood, they can have a child with O- blood.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  225. Megan

    Hello. I’m a little confused because I’ve been doing some research. I don’t know my mothers blood type, but I know mine is ab+ and my dad’s is o. Is this possible? Because from what I’ve read, it isn’t!

    Added:
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    • Hi Meagan,

      You are correct. Our current understanding of science is that it is not possible for one parent to be AB+ and a child that is O. An AB parent can only have children who are A, B or AB.

      It is very wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
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      • Megan

        Well, I’m ab+ for sure because I’ve donated blood and I have a card that states so. My grandparents are both of and so is my father. I’m not sure about my mother, but that’s what I was getting at, my father, if he is, haha shouldn’t be on? And what are the chances of the impossible being possible?

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  226. Rose

    My bf is b- his son is b+ an his baby mom is o + could this be his son even if she took plan next morning

    Added:
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    • Hi Rose,

      If one parent is B- and the other is O+, they can have a child that is B+.

      No birth control is 100% effective.

      To determine if your bf is this child’s biological father, a DNA paternity test is in order. They are 99.999% accurate.

      I hope that’s helpful.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  227. Dionne

    Hi doc
    What could be my blood type if my mom’s blood type is AB+ while my dad’s blood type is 0+?

    Added:
    Reply
    • Hi Dionne,

      If one parent is AB+ and the other is O+, each of their children could be A+, A-, B+, or B-.

      If you’d like further explanation, please let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
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      • Paul Thomasson Tveit

        My mom is AB negative and I am O positive…

        my brother of the same mother is O negative

        I am not sure of my dads type but the three of us are known…

        it has to be possible, because it is.:/

        Added:
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        • Paul Thomasson Tveit

          lol she is B negative.:P

          Added:
          Reply
          • Paul,

            Mystery solved!

            Thanks for letting us know.

            Best,
            @MsGreene

            Added:
        • Hi Paul,

          Are you sure all the blood types are correct?

          @MsGreene

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      • bribe queen

        Please I need clear explaination on if one parent is ab+ and other o+ their child B-Day.

        Added:
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        • Dear Bride,

          Blood types are made of two alleles for the A,B,O type and two for the Rh type. Children get one letter allele and one Rh allele from each parent.

          If one parent is O+, his or her alleles could look like this:
          O+ can be OO++ or OO+-

          If the other parent is AB+, his or her alleles could look like this:
          AB+ can be AB++ or AB–

          If the child is B-, his or her alleles could look like this:
          B- can be BB– or BO-

          That means:
          If the first parent is OO+- he or she can only pass down an O allele, but could pass down an Rh-
          If the second parent is AB+ he or she can pass down either A or B and either + or –
          Then the child received an O from parent one, a B from parent two, and Rh-s from both to be B-

          Does that make sense to you?

          Best, @MsGreene
          Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

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  228. Heather

    My mom is o+ and my dad is a-, what would that make my blood type?

    Added:
    Reply
    • Hi Heather,

      If one parent is O+ and the other is A-, each of their children could be O+, O-, A+ or A-.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com

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  229. Corey

    Question….I am A+ and my boyfriend is AB+ we have 2 boys… What might their blood type be….one more question…he is wondering if he has another child but her blood is O- could he be the father???

    Added:
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    • Hi Corey,

      If one parent is A+ and the other is AB+, each of their children could be A+, A-, B+, B-, AB+ or AB-.

      A parent who is AB+ can not have a child who is O+ or O-.

      If you’d like an explanation, let me know.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  230. Ariel bohanan

    If I have rh- blood and I am the mother , and my child has O+. What blood type could the father possible have to be my kids father? One says he’s O+, so is he the father ?

    Added:
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    • Ariel,

      If your child is O+ and you are A-, B- or O-, the father could be O+.

      If you are A-, B- or O-, the father could also be A+ or B+.

      Basically, in this situation, if you really want to determine who the father is, you’ll need a DNA paternity test because there is no one type of blood that would result in a child who is O+.

      Sorry I can’t be more helpful.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      P.S. I assume your doctor discussed your blood type incompatibility issues?

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  231. Alyssa

    Hello, i have O postive blood type rh positive, my husband has AB positive blood

    Our Daughter has O positive

    And when our son was born he had to go under the light because they said something about ABO factor?

    Whats that mean?

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  232. Joella

    Hello. So my dad is O- and my mom is A+ but I’m B+?? That isn’t possible is it?

    Added:
    Reply
    • Joella,

      Our current understanding of science is that it is not possible for one parent to be O-, the other parent A+ and a child that is B+. An A+ parent can only have children who are A+, A-, O+ or O-.

      It would be wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
      Reply
  233. Jennifer Flynn

    Is there a possilbity that O- male and a AB+ female have a A- child

    Added:
    Reply
    • Hi Jennifer,

      Yes, it is possible for one parent to be AB+, the other to be O- and their child to be A-.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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      Reply
  234. Mohammad Rafiq

    If father and mother both has blood group A- then what would be there children’s blood group

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    • Hello Mohammad,

      If both parents are A-, each of their children could be A- or O-.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  235. lorraine

    Both my parents are O I think one is – and one + I am A+ and pretty sure this should not be the case but is it possible for two O blood group parents to have an A baby? At all?

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    • Lorraine,

      Our current understanding of science is that it is not possible for one parent to be O-, the other parent O+ and have a child that is A+. If both parents are O, all their children will be type O.

      It’s very wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  236. Katrina Nadminty

    Hello I am B+, my husband is O+ what blood type will my son be. Thank you

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    • Katrina,

      If one parent is B+ and the other is O+, each of their children can be B+, B-, O+ or O-.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  237. Kathy Lunt

    I’m A negative…neither my mother or father is A or negative..can this happen?

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    • Kathy,

      Our current understanding of science is that it is not possible for a child to be A if neither parent is type A. It is possible to be Rh- if neither parent is Rh-, though.

      In your situation, it would be wise to have all your blood retested before jumping to any conclusions. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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      • Kathy Lunt

        Thank you…this was a comment my mother made after I became an adult, saying she didnt know how i could be A- when neither she nor my fathet were either.

        Added:
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        • Perhaps she meant neither of them were A-. Perhaps one of them was O+ and the other A+. It would then be possible for their child to be A-.

          @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom

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  238. Terboyen Zak

    Hello Dr, I am O+ and so is my wife can we have children?

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    • Terboyen,

      There is no reason, based on blood type, that two O+ parents can not have healthy children.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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    • S. Wilson

      The only issue comes when one parent has a negative rh and one a positive, e.g. Mom is A – and dad is A +, then you risk the baby being a pos Rh type that could cause complications during later pregnancy if somehow, (there’s always a chance but as the mother and infant do not share blood systems, the issue would probably occur in later pregnancy, or delivery) the baby’s blood were to enter the mother’s system, the mothers body would attempt to create antibodies to fight against the baby’s blood. However, there are ways to reduce risks and have a fairly healthy pregnancy and a completely normal baby. It is important to let your ob/gyn know at your first check up if the parents have different rh types so that he/she will be prepared for any future complications. They will most likely do a shot called Rh immunoglobulin (RhIg) that basically prevents the mom from developing antibodies against the baby. If you’re concerned, talk to an ob/gyn, they deal with this stuff all the time.

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  239. Abdul Razak

    Hi Dr, my wife and i belong to blood group O can we have children? Thank you.

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    • Abdul,

      O is the most common blood type. The only issue with two people with type O blood having children is if the mother is O- and the father is O+.

      Dr. Greene addresses this issue in the Q&A How To Determine and Manage Rh Incompatibility.

      I hope that’s helpful,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  240. Sue

    If mother is A- and father B- can baby be O+

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    • Sue,

      No, if one parent is A- and the other is B-, they can not have a child who is O+. They can have a child who is O-, but not O+. If one of the parents is Rh+ and the other is negative, the child can be Rh+.

      In this case, it would be very wise to have the blood types retested. It would be very easy for one of the types to be different than people remember.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  241. martin

    if the mother was o-
    and her son is o- is it possible for daughter to be ab-?

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    • Martin,

      Our current understanding of science is that it is not possible for a parent who is O- or O+, to have a child that is AB- or AB+. An O parent can only have children who are A, B or O.

      It would be wise to have mother and AB child’s blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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  242. ali

    I have ab- my wife have o+ is possible we have child with o- or not possible plz reply thanks or its wrong test of our baby blod

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    • Ali,

      Our current understanding of science is that it is not possible for one parent to be AB-, the other parent O+ and a child that is O-. An AB parent can only have children who are A, B or AB.

      Very wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

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      • ali

        But sir i read some way that if one Parent have abo blod and other have o blod then they can have o blod baby. And that is normally happen in India or Asia I m from Pakistan what is different in ab- blod and abo how can I test my bold

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        • Ali,

          I am not a doctor (Dr. Greene is a different person, I am MsGreene). I do not know about a blood type ABO, only A, B, AB and O. Can someone else help shed light on this?

          Best,
          @MsGreene

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  243. Bawi Kim

    Both my parents are AB blood type, what will be mine then?

    Added:
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    • Hi Bawi,

      If both parents are AB, their children can be A, B or AB, but not O.

      Best,
      @MsGreene

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  244. daris

    I have my blood group group A- and my father and mother have A+ can it be possible

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  245. Judy Ammons

    I am A- what would my father’s blood type be?

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    • Hi Judy,

      If you are type A-, depending on what type blood your mother has, your father could be A, B, AB or O. He could also be + or -. This is not the case with every blood type combination. For instance, if you were type O, he could not be type AB, no matter what type blood your mother has.

      Best,
      @MsGreene

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    • Helen

      I’m o- what would my parents have to be?

      Added:
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      • Helen,

        As it turns out, that is one blood type that could have one or both parents from A+, A-, B+, B-, O+ or O-. The only blood type your parent can not have is AB+ or AB-.

        If you’d like an explanation, let me know.

        @MsGreene

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        • Paul Thomasson Tveit

          this can’t be true.. my brother IS O- and our mother IS AB –

          I am O+, myself…?

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          • Paul Thomasson Tveit

            lol Mom is B negative.:P

            I misremembered…I guess… memory is a fickle thing I guess.:P

            Added:
          • Paul,

            Thanks for sharing and this is a great example of how often people are sure they know blood types and one of them is different than what they thoughts. Sometimes this is due to a lab error, or a reporting error, or as you point out, memory is a fickle thing.

            Thanks again,
            @MsGreene

            Added:
          • Paul,

            If you are correct, call the New York Times. You’re making history! Or perhaps your mother’s blood type is different than you think?

            Best,
            @MsGreene

            Added:
  246. Helen

    Can myself as the mother having O+ blood type make A+ baby with one guy has ab+ and other has ab- which one could be father?

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    • Helen,

      In this case, blood type alone can’t rule out either man.

      1. If the mother has O+ blood and the father has AB+ blood, it is possible to have a child with A+ blood.
      2. If the mother has O+ blood and the father has AB- blood, it is possible to have a child with A+ blood.

      DNA paternity testing, which is 99.999% accurate would be needed to determine paternity. You can do these tests at home. Here’s one example. It’s low priced, but not legally binding. This test legally admissible.

      I hope this is helpful,
      @MsGreene

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  247. Mimi

    Hello, please I’m O+ and my husband B+. Is it possible that our child could be AA or A+?

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    • Mimi,

      Our current understanding of science is it is not possible and one parent to have O+ blood, the other to have B+ blood, and their child to have A+ blood.

      It would be wise to have everyone retested. One of the blood types may be different than you think.

      Best,
      @MsGreene

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  248. Seema

    Hi Doctor
    I am AB + and husband is B+ We have 3 children oldest has AB+
    Middle one is B+ youngest is ,A+
    Can you explain what does my younget one has A +

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    • Hi Seema,

      Yes! I can explain.

      If a person is AB+ he or she has one A and on B allele and can pass down either an A or a B to each of his or her children.

      If person is B+ he or she has either two B alleles or a B and an O allele. In the example you provide, we can determine that the father has a B and an O allele so he can pass down either a B or an O.

      Oldest child get A from mom and B from dad = AB
      Middle child gets B from mom and B from dad = B
      Youngest child gets A from mom and O from dad = A

      Make sense?
      @MsGreene

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      • Honey

        Can Seema AB+ and her husband B+ have a baby with O+?

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        • Honey,

          Our current understanding of science is that it is not possible for one parent to be AB+, the other parent B+ and a child that is O+. An AB parent can only have children who are A, B or AB. However, it’s not uncommon for blood types to be different than they are remembered. It would be prudent to have all three blood retested.

          @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom

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  249. Asiog

    My blood type is O+ my parent’s are O+ and my sister is B+ how is that???

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    • Asiog,

      Our current understanding of science is that it is not possible for two parents with O+ blood to have a child with B+ blood.

      Before you jump to any conclusions, it’s wise to have everyone’s blood retested. The types may be different than what you think they are.

      @MsGreene

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  250. gabby

    my mother is A+ and my father is O- and I’m A-. my boyfriend’s father is O+ and his mother is A+ and my boyfriend is O+ and our child is A- can you explain our blood types

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    • Gabby,

      Maternal Grandmother = A+ which is either AA or AO and ++ or +-
      Maternal Grandfather = O- which is OO and – –
      Child = A- who got an A from mother, an O from father and negative from each

      Paternal Grandmother = A+ which is either AA or AO and ++ or +-
      Paternal Grandfather = O+ which is OO and either ++ or +-
      Child = O+ who got O from each parent and a + from at least one parent (O+ can be OO++ or OO+-)

      Mother = A- which is either AA or AO and – –
      Father = O+ which is OO and can be either ++ or +-, but we assume is +- based on child’s outcome
      Child = A- which A from mother, O from father and – from both

      Cheers,
      @MsGreene

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      • gabby

        thank you very much

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  251. Rebecca R

    Hi
    My father is o +
    My mother is A+

    I am resus A negative is this possible please
    Thank u

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    • Rebecca,

      Yes, this is possible.

      Let me know if you’d like an explanation.

      @MsGreene

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  252. Vhan

    Hi. Im sure im not O but i cant remember if im a positive or negative B. My dad’s B+ while mom is O.

    Added:
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    • Vhan,

      If one parent is B+ and the other is O, it is possible for their child to be B+, B-, O+ or O-.

      @MsGreene

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  253. Erika

    I am B positive my boyfriend is B positive why is my son B negative?

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    • Hi Erika,

      Each person has to Rh alleles. They are positive (+) and negative (-).

      We call a person Rh+ if they are two positive alleles ++ or one positive and one negative +-.

      Each parent passes down one allele to his or her child.

      In the case of two B+ parents and a B- child, both parents would be +- and each of them passed down the – allele so the baby is – – or Rh-.

      Does that make sense?
      @MsGreene

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  254. smile

    My dad is O- am B-(female), my two younger brother’s are A- and 0-…pls what could my mum blood group

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    • Hi Smile,

      If one parent is O- and his or her children are B-, A- and O-, the other parent of the children who are B- and O- would be B+ or B-, the other parent of the children who are A- and O- would be A+ or A-.

      Before you jump to any conclusions, it’s wise to have everyone’s blood retested. It’s not uncommon for one of the blood types to be different than what you all think it is.

      Best,
      @MsGreene

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      • smile

        Ok…..
        So it means it z possible for a couple to av kids wif 3 different blood groups.

        Added:
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        • Smile,

          It is possible for some parents to have children with three (or even four) different blood groups. For instance if one parent is blood group A, the other is blood group B, they can have children who are A, B, O or AB.

          Best, @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

          Added:
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  255. Rashida

    My blood type is B+ and my husband blood type is A+
    What will be my son’s blood type A+ B+ or AB+

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    • Rashida,

      If one parent is B+ and the other is A+, each of their children could be A+, A-, B+, B-, AB+, AB-, O+ or O-. As you can see, this combination of parents offers the greatest possible outcomes.

      If you’re interest in an explanation, let me know.
      @MsGreene

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  256. NleeM

    My blood type is AB+. I have a sister A+ and another sister O+. My parents are deceased but I thought my father was O+ – is that possible and what might my mother have been? If my father was not really O+ what possible blood types could my parents have been in view of children being AB+, A+ and O+?

    Added:
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    • NleeM,

      If three siblings are AB+, A+ and O+ one parent could be A+ or A- and the other could be B+ or B-.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  257. Cody

    In this article you mention that having parents that are type (a) and one type (b) can produce all other blood types. However on the redcross site it states I can only be (a) or (o). Can somebody clarify this for me? Thx.

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    • Please send a link to the Redcross page where you saw this result.

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  258. Danial

    Hi Dr,

    My blood group is ABRh+ and my partner’s blood group is B+. We are very curious to know all the possible and impossible blood groups and the “Rh” that our children may have.

    Regards,
    Danial

    Added:
    Reply
    • Daniel,

      If one parent is AB+ and the other is B+ their children can be B+, B-, A+, A-, AB+ or AB-. They can not be O+ or O-.

      Cheers,
      @MsGreene

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  259. Becky

    Hi if I am A Resus Negative blood is it possible to have both parents O positive

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    • Hi Becky,

      Our current understanding of science is that it is not possible for two parents who are O+ to have a child who is A-.

      It is not uncommon for one of the three blood types to be different than thought, so it is wise to talk to your parents about having everyone’s blood type re-tested before jumping to any conclusions.

      Best,
      @MsGreene

      Added:
      Reply
  260. Jessica

    Dear Dr. If I am o positive and my husband is ab positive what blood type could our son be

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    • Hi Jessica,

      If one parent is O+ and the other is AB+, their children can be A+, B+, A- or B-.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene

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      Reply
      • Ar anne

        Why AB is cant? And O?

        Added:
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        • Hi Jessica,

          Each parent passes down one allele. A, B, and O are the most common one by far. Each parent also passes down one Rh allele, either + or -.

          If one parent is AB+, that parent can pass down an A or a B. People who are RH+ can be ++ or + -, so that parent can pass down a + or a -.

          If the second parent is O+, that parent has two O alleles and can only pass down an O allele and can pass down a + or a -.

          The AB parent rules out the possibility of an O child. And the AB parent rules out the possibility of an AB child.

          Does that make sense?

          @MsGreene

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  261. Nicola

    Hi,
    My Mother is blood type A and my father is O . But I’m a B Positive and my younger sister is O type same as my father .
    I read on here that A and O type is impossible to have a B Positive child . If this is correct ,it could mine that my father is not my biological father after all .
    Really confused

    Thank you .

    Added:
    Reply
    • Hi Nicola,

      Our current understanding of science is that it is not possible for a parent who is A and a parent who is O to have a child who is B.

      It is not uncommon for one of the three blood types to be different than thought, so it is wise to talk to your mother about having everyone’s blood type re-tested before jumping to any conclusions.

      Best,
      @MsGreene

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      Reply
      • Nicola

        Thank you for your Advice .

        I have had my bloods done four times ,due to having my babies . So I do know that my blood group B Pos is correct
        Maybe one of my parents blood group is wrong .

        Thank you again

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  262. Stela

    Me and my partner are o positive, and my child is a+ is that possible?

    Added:
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    • Stela,

      Our current understand of the science is two O+ parents can only have children who are O+ or O-.

      It is not uncommon for blood tests to be in error or to be recorded in error. It’s wise to have all three types re-tested before drawing any conclusions.

      Best,
      @MsGreene

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      Reply
  263. Josie

    Im just wondering im ab postive and my mum is a postive dad is b postive but no other sibling seems 2 know why im ab postive cause there either a or b . Confused

    Added:
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    • Hi Josie.

      Each individual has two alleles that comprise their blood types. The most common are A, B and O.

      — If a person is type A, he or she can be AA or AO.
      — If a person is type B, he or she can be BB or BO.
      — If a person is AB, he or she is AB.

      Every child get one allele from each parent. In the example you give:
      — One parent contributed an A and the other a B, so the child is type AB.
      — One parent contributed an A the the other an O, so the child is type A.
      — One parent contributed a B and the other an O, so the child is type B.
      — If (which is not in your example) both parents contributed an O, the child would be type O.

      In other words, if one parent is type A and the other is type B, they can have children who are A, B, O or AB.

      Does that clear up your confusion?
      @MsGreene

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  264. Lala

    Is it possible that my child is B+ and me and his father is O+? Is there any instances that already happened?

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    • Lala,

      I’m not aware of an instance where that has happened.

      Have you confirmed test results?

      @MsGreene

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  265. Andrea

    Hello, I am O+, my daughter is A- and I am trying to figure out my son’s blood type. My husband doesn’t know his own. What are the possibilities for their blood type? Thank you in advance!

    Added:
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    • Hi Andrea,

      It takes two alleles to make up a blood type and two to determine Rh factor. If you are O+ you have two Os (OO) and you are either Rh+ or Rh- so you can pass down an O and either a + or a -.

      If your daughter is A- she can be AA or AO and can only be – -. That means she would have gotten an A from her father, an O from you and a – from each of you.

      If the two are true, then her father is either A+ or A- and each of your children could be O+, O-, A+ or A-.

      Does that make sense?
      @MsGreene

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  266. Sasha

    Hi, Dr. Greene I am O+ and my mom is Rh-. Is there any concern here because I bleed alot when I go to the dentist for an extraction or menstrual cycle.

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  267. NB

    My blood type is A+ and my husband’ blood type is B- .Our son has A- blood.. Is my husband my son’s dad?

    Added:
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    • NB,

      In this example: mother A+, probably father B-, child A-, the blood type does not rule out that the probable father is the father. Nor does it prove that he is the father.

      DNA paternity testing is 99.99% accurate and can be done at home.

      I hope that helps,
      @MsGreene

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  268. anita

    Mother is 0- and father is 0+ and child is B+, is it possible?

    Added:
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    • Anita,

      According to our current understanding of science, a parent with O- blood and a parent with O+ blood can only have children who are either O+ or O-.

      Of concern, in the example you provide is the mother is Rh- and the child is Rh+. If this is the situation, the mother needs medical treatment before conceiving again. Dr. Greene explains in his Q&A How To Determine and Manage Rh Incompatibility.

      Best,
      @MsGreene

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  269. Husny

    Dear doctor,
    My blood type is AB while my moms bloodtype is O and my dads bloodtype is B and i’m their biological daughter. How is that possible?

    Added:
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    • Husny,

      Our current understanding of science is that a person with AB blood can not be the biological child of a person with type O blood.

      However, it is not uncommon for one of you to have a different blood type than you think you have. This can be because the blood type test was in error, it was recorded incorrectly, or someone remembers it differently than was reported. In any case, it’s wise to have the child with AB blood and the parent with O blood retested.

      I hope that is helpful,
      @MsGreene

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  270. Angel perlas

    My both parents are type O but one of the siblings is type AB? Can it be possible?

    Added:
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    • Angel,

      According to our current understanding of science, if both parents are type O, and the child is AB, neither of the parents are biological parents.

      Options — have everyone’s blood type retested, have a conversation about biological vs adoptive parents, remain silent. All are valid responses.

      Best,
      @MsGreene

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  271. Pam

    If I am ABt can I have a parent AB t

    Added:
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    • I am unfamiliar with “t” in blood type distinction, but assuming it is either + or -, the answer is, yes.

      If one parent is AB+ or AB- s/he can have a child who is the same type IF the other parent is either A, B or AB, but not if the other parent is O.

      If you’d like to clarify the meaning of “t”, I can answer more fully.

      Best,
      @MsGreene

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  272. Dr:Kayla

    It’s Not normal if parents blood group is Orh+ but the child blood group is Orh-
    Dr:Kayla

    Added:
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    • Actually, is it normal. Here’s why —

      • Blood types are comprised of two alleles. Each is positive (+) or negative (-).
      • If a person is Rh- blood type, both alleles are negative.
      • If a person is RH+ blood type, he or she can have two positive alleles or one positive and one negative.
      • If both parents have one positive allele and one negative, and both pass down the negative allele, their child would have two negative alleles and be Rh-.

      Does that make sense to you?
      @MsGreene

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  273. James

    If a mother blood type is Orh+ and the father blood type is also Orh+
    But child was Orh- is it possible?

    Added:
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    • James,

      Yes, this is possible. If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  274. ashley Brumbaugh

    I am O + my baby is also o+ can her dad be a+

    Added:
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    • Ashley,

      Yes, that is a possible combination. In fact, that’s a common outcome.

      Best,
      @MsGreene

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  275. Niki

    Hi I am O+ and my partner is AB- I wanted to know what precaution measures to be taken during pregnancy ??

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      • Niki

        Thank u sir . I guess no incompatible issue

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  276. Mary

    If mother and father are both 0+ will baby be same

    Added:
    Reply
    • If both parents are O+, each of their children can be either O+ or O-.

      Best,
      @MsGreene

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  277. Amanda

    Hi Dr, I am O – and my husben is either O+ Or O- What would my baby blood type would be ? Can the baby carry my blood type or only the father ?

    Added:
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    • A baby’s blood type is comprised of half from the mother and half from the father.

      If one parent’s blood type is O- and the other’s is O+, their children can be either O+ or O-. If one parent’s blood type is O- and the other’s is O+, their children can be either O+ or O-.

      The concern in the example you give is if a woman has Rh- blood and her partner has Rh+ blood, there is a incompatibility issue that needs to be addressed. Dr. Greene discusses it in his Q&A How To Determine and Manage Rh Incompatibility.

      Best,
      @MsGreene

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  278. Frost

    If my son AB+ the mother is A- I do not currently know my blood type. My mother is B+ and my father is O+. What could my blood type be?

    Added:
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    • If a child is AB+ and one parent is A-, the other parent is B+.

      Hope that helps,
      @MsGreene

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  279. Anju

    I’m A+ and my husband is Ab- will there be any prblm wid the child??.

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    • There are not health issues associated with the blood types of a mother who is A+ and a father who is AB-. The health issues from blood type imcompatibility are associated with a mother who is Rh- and a father who is Rh+.

      Best,
      @MsGreene

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  280. Lucy

    Hi Dr Green,
    Mum A-
    Dad A +
    What could the children be please?

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    • Hi Lucy,

      If one parent is A- and one parent is A+, each of their children could be A+, A-, O+ or O-.

      Of concern, if the mother is Rh- and the father is Rh+, the mom needs to be treated for potential blood type incompatibility. Dr. Greene discusses why and how in his Q&A How To Determine and Manage Rh Incompatibility.

      Best,
      @MsGreene

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  281. Curious Me

    The article was very helpful thank you. I was a little lost on our situation though, as it looks like many are.

    I am a B+ my husband is an A+
    Our oldest is A+ and our youngest is AB- I guess I’m just wondering where/how the – came in. Super cool to find out we could potentially have a little O baby.

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    • Hi Curious,

      In the RH system, each person has two alleles. Each can be either positive (+) or negative (-). If a person has two negatives, they are Rh-. If a person has one two positives or one positive and one negative, they are Rh+.

      In the example you give, one parent is A+ (and would be +-) and the other is B+ (and would be +-). If each parent passed down a negative allele, the child would be — or Rh-.

      Hope that explanation makes sense.

      Best,
      @MsGreene

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      • Curious Me

        Yes, it does. Thank you so much for taking the time :)

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  282. jo

    If I’m o rhesus negative and my mums o positive what blood group should my dad be

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    • If one parent is O+ and the child is O-, the other parent can be A/B/O, but not AB. The second parent can be Rh+ or Rh-.

      Hope that helps,
      @MsGreene

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      • jo

        Thanx you very much yes it has helped

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  283. chantall

    Dear Dr Green. Can a O+ mother and an A- father have an O+ child

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    • Chantall,

      Yes, an O+ mother and an A- father have an O+ child.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

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  284. Raj

    Dad B+ and mother B+ but son is o+ it is possible

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    • Raj,

      Yes, this is a possible outcome.

      Let me know if you’d like an explanation of how this works.

      Best,
      @MsGreene

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      Reply
  285. Sya

    Hi doc.

    I am AB and my husband is B. But my third son is O. I need explaination because its imposible to us having child with O type. But my husband’s mother is O. Need your explaination. Thank you

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    • Sya,

      If you are really AB (you should be retested to confirm) you can only pass down an A or a B. This means none of your children can be O. If your husband is type B, he could pass down B or O, but a child with type O has an O from both parents. If the blood types you state are all accurate, he could be your husband’s son, but he could NOT be your son.

      Hope this helps,
      @MsGreene

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  286. Rob

    My blood is O+ and my wife is O – what will my child be?

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    • Rob,

      If one parent is O+ and the other is O- their children will be O+ or O-.

      It’s wise to be aware that there is an issue of concern in the situation where the father is Rh+ and the mother is Rh-. Dr. Greene discusses this in his Q&A How To Determine and Manage Rh Incompatibility. If you are not already well versed on this topic, please read his Q&A.

      Best,
      @MsGreene

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  287. Heila

    Hallo,
    Dad is O+ and mom is O-. Can the child be A+?

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    • Hi Hella,

      Our current understanding of the science of genetics is it is not possible for toe parents with type O blood to have a child with type A blood.

      Before jumping to conclusions, retesting my is wise.

      @MsGreene

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      • Heila

        Thank you

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      • Reco

        Hi im o- and my wife is o+ can oir child be any other blood group

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        • According to our understanding of the current science, two parents with type O blood can only have children with type O blood. If one parent is Rh+ and the other is Rh-, the children can be either Rh+ or Rh-.

          Best,
          @MsGreene

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  288. Amaan

    This post was really helpful. Thanks.
    I have B+ and my wife is A+. Our new born girl is O-… Is it normal?

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    • Amaan,

      Yes, it is normal for one parent to be A+, the other to be B+, and their child to be O-.

      If you’d like an explanation of how that can happen, let me know.

      Best,
      @MsGreene

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  289. Karen

    Is there a Dna test to discover if parents were really siblings?

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    • Karen,

      Yes, there are DNA tests that can check to see if two people are siblings. Here is one example*. This one is not legally binding, but I think you are just trying to find out, and there is no court case involved.

      *Note: the test I linked to is not reviewed, it is just an example of what is available.

      Hope that helps,
      @MsGreene

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  290. Kerry

    My blood type is A and my husbands’ is B. My baby has O … does this match with us?

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    • Kerry,

      Yes, if one parent is A and the other is B, they can have a child who is O.

      Let me know if you’d like an explanation of how this can happen.

      Best,
      @MsGreene

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      Reply
  291. Joy

    My father has B+, my mother has A+. I am a boy have AB-. Is it ok?

    Added:
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    • Yes, it is very normal for a B+ parent and an A+ parent to have an AB- child. No worries.

      Best,
      @MsGreene

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  292. Venessa

    Hi. Both my girls are Type A+ and my step daughter is A-
    My blood type is O- my Step daughter’s mom is also O-
    What blood type would their father be?

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    • If two children have A+ blood and one child has A- blood and they all have the same father, and all of them have a mother who is O-, the father would be A+.

      If you’d like further explanation, please let me know.

      Best,
      @MsGreene

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      • Helen

        Can a o+ and ab+ make A+baby?

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        • Helen,

          Yes, if one parent is O+ and the other is AB+ they can have a child who is A+.

          Let me know if you’d like an explanation.

          @MsGreene

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  293. Jane

    If both parents are B+ do all kids have to be B+or O+?

    Added:
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    • If both parents are B+, they can have children who are B+, B-, O+ or O-.

      Best,
      @MsGreene

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  294. Terry

    Can Type B and O Positive have Rh O negative child??

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    • Yes, if one parent is B+ and the other is O+, they can have an O- child.

      If you’d like an explanation, let me know.

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      • Love

        Pls I would like an explanation on this

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        • Hi Love,

          Blood types are comprised of two alleles. The most common are A, B and O.

          People with type B blood can have two B alleles or one B and one O –> BB or BO.

          People with type O blood can only have two O alleles –> OO

          Similarly, people who are Rh+ can have two positive alleles or one positive and one negative allele –> ++ or +-

          People who are Rh- can only have two negative alleles –> – –

          In the example of one parent who is B+ and the other is O+, with an O- child, the each parent passed down an O allele and each parent passed down a negative allele.

          Does that make sense?

          @MsGreene

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  295. Nikki Gloom

    ok A man and a woman have a child. she is AB- he is O what would the variables be of blood type. can it also be AB-?

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    • Hi Nikki,

      If one parent is AB-, that parent can pass down an A or a B, but can only pass down a – (if someone is Rh- it means he or she has two – alleles). If someone is O, that parent can only pass down an O (if someone is blood type O, both alleles are O). If this situation, their children can be:
      AO, which is called simply A
      BO, which is called simply B

      Their children can not be:
      OO
      AB

      If the parent with type O blood is +, their children could be:
      A+
      A-
      B+
      B-

      If the person with type O blood is – (and the other parent is AB-) their children could be:
      A-
      B-

      I hope that’s helpful.

      Best,
      @MsGreene

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  296. Christal

    Hi there! I would like to know what if me and my partner have same blood group type B, will we have a normal baby or is there likely a risk/advice not to have babies?

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    • Christal,

      The issue with blood type incompatibility comes, not from the A,B,O type, but the Rh factor. If the mother has Rh- blood and the father has Rh+ blood, there may be an issue for children after the first child. Dr. Greene explains this in-depth in his answer How To Determine and Manage Rh Incompatibility.

      Best,
      @MsGreene

      Added:
      Reply
  297. Kylei

    Hi! If im type O positive and my husband is type AB positive, can we have a type O positive baby? Thanks

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    • Kylei,

      Our current understanding of the latest science would say it is impossible for a parent with AB blood type to have a child with type O.

      Before jumping to any conclusions, consider having all three parties blood types retested. It’s not uncommon for the test to be in error or for the test results to be recorded in error.

      Best,
      @MsGreene

      Added:
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      • Kylei

        Thanks for the reply, my friend ask if both parents are type O positive what will be the possible blood type of their upcoming baby, thanks again, God bless!

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        • If both parents are O+ their children will be O+ or O-.

          @MsGreene

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  298. Mish

    If mother is O positive and the 2 children are blood types O positive and A negative, what would their fathers blood type be?

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    • Hi Mish,

      If a parent is O+ and has one child who is O+ and the other who is A- with the same partner, the partner could be either A+ or A-.

      If you would like further explanation, let me know.

      Best,
      @MsGreene

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      Reply
  299. Bob

    Is it possible for me to father my ex wife’s son I had a vasectomy six years ago. Her son is now 18 months and he looks a lot like are son. (Who looks alot like me) My ex wife’s blood type is 0-, the other guy is A+ and I’m B+ and my ex wife’s son is B+.. Is it possible for me to be the father of her son??

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    • Bob,

      Based on blood types and our current science:
      — If one parent is O- and the other is A+, they can not have a child who is B+
      — If one parent is O- and the other is B+, they can have a child who is B+

      DNA paternity testing like this one, is much more precise than blood type alone.

      Hope that’s helpful.
      @MsGreene

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  300. Lynn

    Is it possible for a O negative mother and A positive father to have a B positive baby

    Added:
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    • According to our current understanding of the latest science, it is not possible for an O- parent and an A+ parent to have a B+ (or B-) child.

      Best,
      @MsGreene

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      Reply
  301. Bev

    Can an A possitve mother and O negative father have a Rh A negative baby ?

    Added:
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    • Hi Bev,

      Yes, it is possible for an A+ parent and an O- parent to have an A- child.

      In the A,B,O system each person has two alleles that make up their blood type. The A and B are dominant and the O is recessive.

      If a person is type A, he or she can be:
      AA
      AO (since O is recessive, the A is used for the blood type)
      If a person is type O, he or she can only be:
      OO

      Similarly each person has two alleles that make up the Rh system. Positive (+) is dominant and negative (-) is recessive.

      If a person is Rh+, he or she can be:
      + +
      + –
      If a person is Rh-, he or she can only be:
      – –

      In the example you give one parent is AA or AO and + + or + -. The parent can pass down A or O (but not both) and + or – (but not both. The other parent is O- so can only pass down O and -.

      If the A+ parent passes down A and – and the O- parent passes down O and -, their child would be AO – – or A-.

      Hope that’s clear,
      @MsGreene

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      • Mary

        Thanks for adding this to your initial overview. It is an excellent explanation of why I am O- and my daughter is O+.

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  302. Ahmed

    If my mama is Ab and my baba is BA what’s my blood type? Please help its urgent

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    • I’m not sure I understand your question, but what I think you are saying is there is a grandmother with AB and a grandchild with BA (which is known as AB — they are the same thing) blood types. What is the blood type of the child of the grandmother who is also the parent of the grandchild? If that is correct, the blood type is A or B.

      I hope that’s helpful.

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  303. Cindy

    Can an A+ mom and an O- father have an A – child

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    • Hi Cindy,

      Yes, an A+ parent and an O- parent can have an A- child.

      Let me know if you’d like further explanation.

      Best,
      @MsGreene

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      • Cindy

        I would love an explanation

        Added:
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        • Hi Cindy,

          You asked: “Can an A+ mom and an O- father have an A – child”.

          In the A,B,O system each person has two alleles that make up their blood type. The A and B are dominant and the O is recessive.

          If a person is type A, he or she can be:
          AA
          AO (since O is recessive, the A is used for the blood type)
          If a person is type O, he or she can only be:
          OO

          Similarly each person has two alleles that make up the Rh system. Positive (+) is dominant and negative (-) is recessive.

          If a person is Rh+, he or she can be:
          + +
          + –
          If a person is Rh-, he or she can only be:
          – –

          In the example you give one parent is AA or AO and + + or + -. The parent can pass down A or O (but not both) and + or – (but not both. The other parent is O- so can only pass down O and -.

          If the A+ parent passes down A and – and the O- parent passes down O and -, their child would be AO – – or A-.

          Hope that’s clear,
          @MsGreene

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  304. Reynald

    If Im B+ and my wife is O rh + what type of blood my kids should be.

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    • Hello Reynald,

      If one parent is B+ and the other is O+, each of their children can be:
      B+
      B-
      O+
      O-

      Let me know if you’d like more information about how this is determined.

      Best,
      @MsGreene

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  305. Sachin

    My blood group is B positive, my wife blood group is A positive.
    What is my child”s blood possibilities? Please, urgent

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    • Sachin,

      If one parent is B+ and the other is A+, each of their children could be:
      AB+
      AB-
      B+
      B-
      A+
      A-
      O+
      O-

      As with the your previous question, about one parent who is B- and the other who is A+, all these types are possible.

      See Dr. Greene explanation above for the details of how this can happen.

      Best,
      @MsGreene

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  306. Sachin

    My blood group is B negative, my wife blood group is A positive.
    What is my child”s blood possibilities? Please, urgent

    Added:
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    • Sachin,

      If one parent is B- and the other is A+, each of their children could be:
      AB+
      AB-
      B+
      B-
      A+
      A-
      O+
      O-

      Dr. Greene explains how this can be in the article above.

      Best,
      @MsGreene

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  307. Alli

    I am AB positive but my mother is B and my dad is O is it possible for my father to be my real father?

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    • Alli,

      According to our understanding of the latest science, a B parent and an O parent can’t have an AB child.

      That said, tests can be in error or recorded in error. Before jumping to any conclusions, it’s wise to have everyone retested.

      DNA paternity tests are even more sensitive and can give further information.

      Best,
      @MsGreene

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  308. July

    my father is O- my mother is A + and i am B+ they tell me that my father is my real father is that true i don’t care but would like to know

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    • It sounds like it would be wise for all three of you to be retested. If he is your father, one of the tests is in error or was recorded in error.

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  309. sil

    my father is O negative and my mother is A positive i am B positive i’ve been told that he cant be my father is that true im grown i dont care but would love to know

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    • Hi Sil,

      According to our understanding of the current science, an O- parent and an A+ parent can’t have an B+ child.

      Before you jump to any conclusions, it’s wise for everyone to be retested. It’s not uncommon for a test to be in error or recorded in error.

      Best,
      @MsGreene

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      Reply
  310. Celestina Kimberley B.

    Dr. Greene, my sister has an O+ blood group and her boyfriend has the blood group B-. Are they able to have children? Is it safe to have children?

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  311. Tushar

    father blood group Ab+ and mother blood group A+ then poosibale to child blood group O+????

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    • A person with AB+ blood can pass down either an A or a B and either a + or a – (negative is recessive, so someone who is +- is still called +). He or she can not pass down an O. A person with type A+ blood can pass down an A or O ( the O is recessive so someone with AO blood is still called A).

      In the example you provide, AB+ and A+ can not have an O+ child.

      Please keep a few things in mind. We are constantly learning new things and understanding science in new ways. We may find out one day that this is possible and we just didn’t know it.

      Also, it’s not uncommon for a blood type test to be in error or to be recorded in error. It’s wise to have everyone in the family retested before jumping to any conclusions.

      Best,
      @MsGreene

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      • Tushar

        Father blood group B+ and mother blood group A+ then poosibale to child blood group O+??

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