Q: I had my first baby about a month ago, and ever since I have been feeling depressed and overwhelmed. I keep waiting for these feelings to go away, chalking them up to my adjustment to new parenthood, but they haven’t yet. At what point should I seek treatment?

A: Most mothers experience the “baby blues” during the first few days after giving birth. Symptoms include anxiety, irritability and weepiness. They go away over the next two weeks. The cause is unknown. It may be simply exhaustion from labor and delivery.

Postpartum depression is different. Compared to the “baby blues,” it is more severe, is constant throughout the day and also lasts longer. Since you’ve been feeling depressed for at least a month, I suspect you have postpartum depression. This condition can make you feel sad, worthless or guilty. You may find you’re unable to concentrate or take interest in anything, even your new baby.

We don’t know the causes of postpartum depression. Hormone fluctuations are one possibility. During pregnancy, your levels of estrogen and progesterone both rise dramatically. After delivery, those hormone levels plummet. These changes may lead to changes in your mood, sleep patterns, appetite and more.

It’s also possible that some women find the prospect of caring for a new baby very stressful.

Postpartum depression occurs in about five women out of every 100 who have a baby. Postpartum depression is not just a problem for women. Some fathers develop depression during the postpartum period, often when their wives develop depression. But fathers can develop depression in the weeks following the birth of the baby even if the mother is not depressed. In fact, some research indicates postpartum depression is more common in men than women.

If you think you have postpartum depression, be sure to seek help.

Write to Dr. K c/o Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.