First Kicks by Dr. Greene: Track Your Baby’s Development During Pregnancy, by Week

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Expectant moms and dads are full of questions: What should I be eating? What sorts of tests should I have to make sure the baby is okay? How should we prepare for the newborn’s arrival? …And many, many more.

Try to relax, take it one day at a time – enjoy this amazing process – and feel free to read on below for some key insights into your unfolding pregnancy.

What Pregnancy Diet Should I Follow?

During pregnancy, every ounce of baby’s growing body after that very first single cell has come from her mother’s own body. The brain, the heart, the muscles are all built from nutrients that were once part of her mother. The baby is quite literally her flesh-and-blood offspring.

Nutrients that Mom eats during pregnancy, or that she has eaten beforehand, are the exclusive fuel and the only raw material building blocks for the baby’s growth. There is nothing else.

This is a special time. A mother and baby together have different nutritional requirements than either of them will ever have alone. Because the mother is the one doing the eating, we’ll look at these needs from the perspective of changes needed in the mother’s diet.

Sadly, nutrition has not been an adequate priority in mainline medicine. We’ve learned a lot about nutrition in recent years, but much of it hasn’t filtered into physicians’ texts, much less popular parenting books. The data in this post is current as of the most recent Dietary Reference Intakes for each individual nutrient at the time of publication.

Prenatal vitamins are designed with these recommendations in mind. Keep in mind that the handful of vitamins and minerals in the tablets are just the Hollywood stars of nutrition. Each organic whole food contains a cast of thousands of micronutrients that we are just beginning to understand. Some of these important “extras” don’t even have names yet. A diet rich in the variety of organic foods where the “leading actor” nutrients naturally occur is probably the best diet for pregnancy.

The prenatal vitamin is a spectacular safety net. Getting more of these same nutrients from food is generally great, but taking more of them as supplements is unnecessary and unwise.

Read More from: Eating for Two: A Guide to Mother’s Nutrition during Pregnancy
Eating for Two: Folate and Iron
Eating for Two: How Much Folate Do You Need?
Eating for Two: The Gift of Iron
Eating for Two: Vitamin B6 and Iodine
Eating for Two: Zinc
Eating for Two: Niacin, Riboflavin, Thiamin, Pantothenic Acid, and Omega-3
Eating for Two: Not Found in Most Prenatal Vitamins!
Eating for Two: Calcium!?
Eating for Two: Calories
Eating for Two: Liver
Eating for Two: Chocolate
Eating for Two: Eating for the Future

Babies have more taste buds before birth than at any later time. Why would they be designed to form extra taste buds only for them to disappear before they are even born?

Most parents think that before they’re born, babies get all of their prenatal nutrition through the umbilical cord. They don’t realize that babies also drink and digest amniotic fluid, swallowing the equivalent of up to three eight-ounce bottles a day of this nutritious, flavor-rich soup – flavored by what Mom has been eating and drinking. Babies taste, remember, and form initial preferences for these foods. It’s the first step toward Nutritional Intelligence. In my book Feeding Baby Green I described how to make the most of this:

First, you don’t need to do anything. That’s right. Babies are beautifully designed to get to know the real you. They learn about your world from what you eat and drink and from the aromas you smell. This is truly effortless learning and effortless teaching. Your baby is already imprinting on you much in the same way a baby duckling imprints on his mother.

Second, you could do something. We sometimes behave a little better when we know that others are watching. We’re our best selves. Now that you know that your baby is paying attention to what you eat and drink, you might find yourself naturally choosing healthier prenatal nutrition options from whatever is available.

Third, you might plan ahead to share with your baby the tastes and smells you would love for her to love (and perhaps skip, at least for a few months, the tastes you don’t want her to crave). If you need some ideas, you might aim for introducing delicious options from each of the twenty-one plant families listed in the “Biodiversity Checklist” at the end of Feeding Baby Green. These are a wide variety of foods that humans have enjoyed for thousands of years.

How often does a baby need to taste something to form a preference?

We know from animal studies that injecting a flavor into the amniotic fluid even once can make a lasting difference. Even once may be significant for human babies as well—especially for strong flavors.

I recommend that if there is a flavor or aroma you really want your baby to learn, aim for twelve times during the second and third trimesters. This works out to having the flavor at least every other week, on average. Or every week for a shorter burst. Or three times a week for a month.

For more information, see Feeding Baby Green, especially Chapter 4 Middle and Late Pregnancy, and the Biodiversity Checklist appendix, a simple delicious approach to teaching love of a variety of foods during pregnancy, nursing, spoon-fed, finger food, and fork & spoon stages of development.

Should I Get Prenatal Testing Done?

As we all go through this precious life, we inevitably have tests that we must go through. In school, in our relationships, at our doctor’s office.

At about the 4th month of pregnancy, it becomes possible to have tests done to learn more about your baby, if you choose to do so.

There’s a simple blood test called the AFP test.

Right now, proteins and amino acids are passing back and forth between mother’s blood and baby’s. The main protein in baby’s blood is alpha-fetoprotein, or AFP.

AFP is the workhorse of the early bloodstream. It keeps liquid in the vessels and carries molecules from place to place. Much of the embryo’s production capacity is devoted to manufacturing AFP.

The closest thing adults have to AFP in their blood is called albumin.

It’s said that AFP serves no purpose in the mother’s body, but I disagree. I suspect it provides a hidden signal to her body, communicating about the growth and well-being of the baby or babies.

If the baby has a neural tube that has not closed properly, the amount of AFP that spills out may be much higher. And with some chromosomal abnormalities like Down syndrome or trisomy 18, the mixed signals from baby’s DNA may lead to less AFP being made.

And so there is a screening test, called maternal serum alpha-fetoprotein, that measures the amount of AFP in mom’s blood.

This test is not intended to diagnose problems, but to screen for pregnancies we may need to follow more closely to look for potential problems. Most people who test abnormally on the AFP test end up having normal babies.

Another test is amniocentesis.

This is a test that can accurately diagnose problems, by analyzing the baby’s chromosomes.

Amniocentesis is an analysis of the amniotic fluid, that mixed drink made by mother and baby together. But to get to this special liquor, a sharp needle must be slipped into the womb, into the baby’s world.

It’s an invasive test that carries some risk. Experts commonly say that the risk of miscarriage is 0.5%.

Because of this risk, it’s typically only recommended in situations where the information gained about chromosomal abnormalities is likely to balance the risk. For example, in women over age 35, or with a positive AFP test.

If you are given the relevant facts to your specific situation in an unrushed manner, then I support whichever choice you make on the matter and your doctor should too. Parents know what they need.

And a final option is called chorionic villous sampling, or CVS.

This test is another technique to get fetal cells for chromosomal and other analysis. The cells may be obtained with a needle through Mom’s abdominal wall or with a catheter inserted through the vagina and cervix.

Either way, ultrasound guidance is recommended. From the studies done on safety, CVS appears to be about one and a half times more risky than regular amniocentesis but safer than earlier amnio.

However, you are also more likely to get ambiguous results with CVS.

The inherent mistakes in these tests underline how important it is that it remains the parent’s choice whether or not to have one or more of these tests.

Abnormal results may cause needless anxiety, but some parents can’t relax without the tests. The choice should clearly be yours, not your doctor’s.

Can You Explain Breastfeeding Benefits?

Of course!

Here is some background information on breastfeeding to help you make the decision for your family that feels right to you.

Many studies comparing the frequency of illness between breast- and formula-fed infants have demonstrated fewer and less severe illnesses in breast-fed infants.

Breastfeeding helps protect against diarrhea, lower respiratory infections, ear infections, bacterial meningitis, and urinary tract infections. Some studies have even suggested a decrease in noninfectious diseases such as eczema and asthma.

How might breastfeeding do this?

  1. Psychological factors. The developing field of neuroimmunology has demonstrated repeatedly that an individual’s psychological state has a direct effect on his or her immune function. Perhaps the nursing experience by itself directly improves the immune status of infants.
  2. Antibodies.All types of antibodies are found in human milk. The highest concentration is found in colostrum, the premilk that is only available from the breast for the first three to five days of the baby’s life, but levels remain high throughout the first year. Antibodies against specific viruses and bacteria increase in response to Mom’s exposure to these organisms. Human milk is environmentally specific: Mom protects her baby against the bugs most likely to be an immediate problem.
  3. Lactoferrin. This is an iron-binding protein found in breast milk but not available in formulas. It limits availability of iron to bacteria in the intestines and alters which healthy bacteria will thrive in the gut. It has a direct antibiotic effect on bacteria like E. coli.
  4. Lysozyme. This enzyme is present at a level 30 times higher in breast milk than in any formula. It has a strong influence on the type of bacteria that inhabit the intestinal tract.
  5. Growth factors. Human breast milk encourages the growth of protective Lactobacilli probiotic bacteria that can inhibit many of the disease-causing bacteria and parasites. There is a striking difference between the bacteria found in the guts of breast- and formula-fed babies.
  6. Allergic factors. The cow’s milk protein used in most formulas is a foreign protein. This takes much longer to digest, and babies can actually develop antibodies to it. The early exposure to these foreign proteins may be a predisposing factor in such illnesses as eczema and asthma.
  7. Carnitine. This is important for fat metabolism. While carnitine is present in both breast milk and formulas, the carnitine in breast milk has a higher bioavailability, so breast-fed babies end up with higher levels.
  8. DHA and ARA. The main long-chain fatty acids found in human milk are still not present in some formulas. These lipids are important building blocks, particularly in the brain and the retina. Some studies suggest that in their absence, babies’ mental and visual development is hampered.
  9. Change. Breast milk adapts, providing the specific nutrients that babies need at each age and in each situation. Your breast milk is unique for your individual infant.
  10. Staying connected. After about 266 days spent in 24/7 contact with you and being nourished from your body, your baby is born with instincts to seek out and feed from your breast. Feeling the warmth of your skin and hearing your heartbeat. Continuing to taste what you taste. Protecting her from illness and giving her the best shot at brain and vision health.

The most important thing is to choose feeding and nurturing solutions that honor both you and your child. And I believe that no one should second-guess your decision, whatever it is.

Breast milk allows you to continue to feed your baby after birth, and to stay physically connected. It is the perfect food for babies. But today’s infant formulas are the best substitutes that have ever been available. Millions of formula-fed babies have grown up healthy, smart, bright-eyed, and strong.

Should We Circumcise Or Not?

If you know that you are having a girl, or if you know that you will have your son circumcised to follow your religious heritage, it might seem like this question is irrelevant.

I’ve found, however, that considering circumcision can provoke strong opinions that can give you insight into yourself as a parent, whether or not you have anything to decide.

Circumcision is a surgical procedure to permanently remove the foreskin, a sensitive part of a boy’s penis.

The inner lining of the foreskin is a mucous membrane that helps keep the head of the penis (also a mucous membrane) soft, moist, and highly sensitized.

The reasons people choose circumcision vary widely: religious or cultural, looking like Daddy, easier to clean, aesthetics, fitting in with peers, promoting good health, and many others.

Whatever your reasons for or against, honor your desires for your son’s well-being. And consider what we have learned about the medical advantages and disadvantages of circumcision.

What benefits and risks have been scientifically established?

  1. Urinary tract infections. Boys who are not circumcised tend to get more urinary tract infections (UTIs) than their peers, especially in the first year of life. Even though infections might be up to 10 times more common in uncircumcised boys, about 99% ill not have a problem either way. By the way, evidence suggests that breastfeeding has a three-fold protective effect against UTIs in uncircumcised boys.
  2. Cancer of the penis. Newborn circumcision (as opposed to later circumcision) does seem to help protect against this devastating cancer later in life. But it’s a rare cancer either way. There are two ways to prevent cancer of the penis: remove the foreskin or keep it clean and healthy with good hygiene. Other important risk factors for developing this cancer include genital warts, having more than 30 sexual partners, and smoking.
  3. HIV. A growing number of studies link non-circumcision in men with increased risk for human immunodeficiency virus (HIV) infection. This makes sense because the mucous membrane of the uncircumcised penis allows for closer connection and exchange of fluids. But safe sexual practices are far more important than circumcision status in the risk of acquiring HIV.
  4. Other STDs. In the same way, it makes sense that uncircumcised men would be at higher risk for other sexually transmitted diseases (STDs). These include syphilis, genital herpes and warts. Practicing safe sex is especially important for circumcised men.
  5. Procedural complications. Somewhere between 0.2 and 0.6 percent of boys having a circumcision have a complication from the procedure, such as bleeding or infection. Severe or life-threatening complications are very rare, but they do occur.

There is no medical reason to recommend the routine surgical circumcision of baby boys. Good hygiene and safe sex practices can solve many of the possible problems either way, but sometimes this is easier said than done.

Your own perspective will be easy to identify: pro, con, or ambivalent. You can learn much from each of these positions.

Your son’s perspective is harder to predict. Perhaps he will want circumcision to continue a family, cultural, or religious tradition. Perhaps his thoughts will be different from yours.

I can’t tell you what your son’s choice would be. But I can tell you that it is far easier to get a circumcision later, if desired, than to successfully attach a working foreskin.

Whatever you choose, make sure it feels right for your family. And if you do decide to circumcise, please make sure your son gets a proper anesthetic, even if someone tries to tell you this is unnecessary or inconvenient.

There’s no need to suffer.

I’m Worried About Sleep Deprivation When Baby Comes. What Helps With That?

When I see families for their babies’ two-month physical, I like to ask them what they wished they had learned before the baby was born.

What, from those magical newborn weeks, do they wish they had known more about? Overwhelmingly, the most common answer is sleep!

You already know what it feels like to be grumpy, contrary, or “not at your best” from lack of sleep. Missing a whole night’s sleep makes you feel rotten.

The surprising truth is that sustained partial, or low-level, sleep deprivation has a bigger effect on behavior than either the short- or long-term total sleep deprivation studied in medical residents.

Interrupted sleep can make people more moody, more impulsive, less able to concentrate, easily frustrated, not to mention tired during the day.

By around four to six weeks after the baby arrives, the cumulative sleep deprivation becomes significant – especially for parents with more than one child.

So let’s talk about how healthy sleep habits begin, and how to match your rhythm to your baby.

Babies actually begin to sleep early in pregnancy. Before mothers miss their first periods, their babies are already taking naps.

Lots of naps!

Adults sleep about ⅓ of the time. Newborns sleep about ¾ of the time. But before birth, babies sleep about 9/10 of the time.

Much of our physical and mental growth happens when we are asleep.

So if babies are such experienced sleepers, with newborns sleeping an average of 16 to 18 hours a day, why do parents become so exhausted?

Because each episode of a baby’s sleep is brief. And most episodes happen during parents’ normal waking hours instead of at night.

Our daily sleep schedule is set by our circadian rhythm, or internal biological clock. This is approximately 24 hours.

It’s a strong tide that affects many bodily functions, such as heart rate, urine production, immune function, drug metabolism, cancer’s susceptibility to chemotherapy, hormone levels, and temperature. We tend to be born at night and die at night.

Surprisingly, while babies do have their own circadian rhythm, it starts out offset by the mother’s by eight hours.

You probably already have a sense of when your baby is the most active and the most quiet. For most families this does not coincide with the parents’ level of activity.

Once your baby is born, one of your first tasks as a family is to begin the slow adjustment of your baby’s and your cycles toward each other. Both sides need to change.

Here are some ideas on how to do this:

  1. Keep the room bright and not too quiet during the day, even when your baby is asleep.
  2. Keep it dark and quiet during the hours you would like him to be asleep (if you’re up with the baby, a dim nightlight can be practical for nighttime feedings.)
  3. Give arousing touch during the day, like playfully handling their hands and feet during the day even if they’re asleep, and only soothing cuddles and rocking at night.
  4. Make lots of eye contact during the day to stimulate your baby, and minimize eye contact at night.
  5. Use an upbeat voice during the day and a soft gentle voice at night.
  6. Sleep or nap yourself (or at least rest) when the baby is sleeping during the day.
  7. If you breastfeed at night, it will often help both mother and baby get drowsy and drift off back to sleep. If you pump, make sure to feed your baby milk at night that was pumped at night. Daytime milk has a different composition and can wake baby up.

I hope this context and these tips help you and your family get some good sleep in the early days.

How Do I Prepare For Labor And Delivery?

When the contractions of labor begin, you know that the moment you’ve all been waiting for is finally approaching.

Very soon now, the unfolding drama of development will shift to a baby you can see and who can see you, and to baby feet you can press on an inkpad and touch to a piece of paper, instead of feel dancing inside your belly.

In many ways though, the wonder of your baby’s continuous development does not change at birth. It’s an everyday miracle that keeps going.


Our roles as parents adjust with each new phase, but they all come down to new ways of doing the same things we did during pregnancy – providing a safe, nurturing, and gently stimulating environment for our children.

But it’s different when you are caring for a baby who’s made his grand entrance.

And this momentous passage can really hurt.

In childbirth classes I’ve attended, the focus has been on the mother’s discomfort, and whether she wants pain relief, or the full brunt of the experience.

But my question is, what does your baby want?

Her body will be going through mirror-image contortions to your own, shrinking where you are expanding, bones pressing together where yours stretch.

She will experience pressures unlike anything she was experienced before or will again, as she is permanently expelled from her paradise, into a wonderful world she has not yet seen.

As she moves towards the light of the outside world, for an instant she is poised in between, no longer able to breathe underwater, not yet having breathed air.

And then comes the first cry – a sound that changes you forever. A new voice in the world.

I wonder, does your baby want pain medication or drugs to make him numb during the earthquake passage? I can see why he might – or might not.

Most babies quickly become calm and curious after the initial cry to get air into their lungs. They seem eager and alert, not traumatized or exhausted.

Unless they get narcotics. Then they are measurably less alert or eager to discover their parents and the world around them.

Epidurals seem to lengthen labor, but don’t seem to have significant effects on various measures of newborn health.

But whether your delivery is by C-section or vagina, whatever anesthesia choices you make beforehand, and whatever is actually done, the moment arrives when you and your baby glimpse each other for the first time.

The baby will be quickly dried and given the Apgar test to make sure he’s ok. Then he will be brought to Mom, and the new family can marvel together.

In some ways, this is a strange new world for your baby. But some things are familiar.

Babies recognize their mothers’ smell, and the sounds of voices that are familiar to them.

Skin-to-skin contact and quiet conversation are a warm welcome to this side of the cervix.

When healthy babies enjoy skin-to-skin contact with their mothers, the are usually amazingly content during the first 90 minutes of life, with little or no crying.

If they are wrapped warmly and placed in a nearby bassinet, however, they cry an average of 20-40 seconds every five minutes for the next hour and a half.

They want to feel safe and warm next to you. And to start getting to know you from the outside.

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I hope you’ve found these insights and tips helpful.

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Wishing you and your baby a beautiful day today!
Dr. Alan Greene

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