Dr. Greene, I have a beautiful 3-month-old daughter that I've looked forward to for so long, but now I can't enjoy her. She's up crying every 2 hours all night and I am overwhelmed and exhausted. My postpartum depression is getting worse. My doctor has prescribed Zoloft, but I'm nervous about it since I'm nursing. Should I take it? Does it come through the breast milk? Should I stop nursing? Help!

More women become depressed while their children are babies than at any other time in life (Clin Pharmacokinet 1994 Oct;27(4):270-89). With the surging tide of postpartum hormones, mounting sleep deprivation, persistent noise, shifting body image, the change of life structure, and the loss of control of one's own time, this depression is not surprising -- even with a brand-new bundle of joy in the home.

For a nursing mother, making the decision to take medicine to treat this depression is tricky. We know some medicines are not safe to take when nursing; others are okay. For most medicines, there is not enough known to do better than make an educated guess. Most of the antidepressants fall into this last category.

Since most medications of any kind taken by the mother do show up in the breast milk, my rule of thumb is that, all other things being equal, it is better for a nursing mom not to take a medicine that is not clearly okay to prescribe for the baby.

In the case of depression, all other things are not equal.

Solid evidence is mounting that maternal depression is not good for babies' development. A study released just last month looked at 225 four-month-old infants, and their responses to the voices of depressed and non-depressed women. Babies do not learn as well when they are listening to the flatter, less melodic voices of depressed women. Adults' perky, high-pitched baby talk sets the stage for intellectual development (Child Development 1999;70:560-570).

Depressed mothers deserve treatment, both for their babies' sakes, and so that the mothers do not miss out on enjoying one of life's unrepeatable joys -- the all-too-brief babyhood of each child.

It’s best to first treat the depression with sleep, exercise, bright light, upbeat music, and healthy food. Exercise is particularly difficult in the postpartum period -- both time and energy are often lacking. But exercise has been proven to help specifically with postpartum depression (J Sports Med Phys Fitness 1997 Dec;37(4):287-91). Cooperation and commitment will be needed from family and friends to guard Mom's sleep and to free her up for daily aerobic exercise -- outside if possible (Prev Med 1999 Jan;28(1):75-85). An hour of aerobic exercise daily can be as powerful as even the strongest antidepressant medications. Even 10 minutes a day can make a noticeable difference.

Anaerobic exercise, while effective at treating depression, creates lactic acid that causes sore muscles. This lactic acid gets into the breast milk. It doesn't taste good and leads to fussier babies -- which in turn increases the risk of depressed moms (Pediatrics 1992 Jun;89(6 Pt 2):1245-7). I also wonder whether depression itself may alter breast milk, giving another good reason to treat.

Even an hour of quiet rest with no responsibilities can significantly improve the depressed symptoms (J Sports Med Phys Fitness 1997 Dec;37(4):287-91). Seeking out support and therapy is also very important.