A: Congratulations on your success with breastfeeding. You've given your son a terrific start in life!

It's true that exclusive breastfeeding delays the onset of menstruation after the baby is born. This lactational amenorrhea occurs because frequent suckling inhibits ovulation, the release of an egg each month. Ovulation is necessary for menstruation, and typically precedes menses by fourteen days. Women who breastfeed exclusively may not have a menstrual cycle for several months.

However, as babies add solid foods and liquids other than breast milk to their diet, most women begin to ovulate, and therefore menstruate, again. Because ovulation occurs prior to menstruation, it is possible for a woman to become pregnant again before she has her first postpartum period!

There are a number of reasons your menstrual cycle may not have returned. You should see a doctor for a full evaluation. You should discuss your medical history, have a physical exam and have laboratory tests to better understand why you're not menstruating. Your doctor will ask about the frequency of your menstrual cycles before you were pregnancy, discuss your current method of birth control, assess your general health and well-being, possibly give you a pregnancy test and order several hormone tests. With this kind of evaluation, you will be able to learn why you haven't yet menstruated.