Is it normal to have periods while breastfeeding post delivery?

Q: I want to know, how long does it take for the uterus to contract fully after delivery? I had my delivery 3 months back and last month I had my periods, not much but little. Now it seems that from this month onwards my regular periods have started. I have heard that lactating mothers don't have periods that early. I hope there is nothing to worry. Please advise.

A:It takes the uterus about 6 weeks post delivery to return to pre-pregnancy size. It is also normal to have regular periods while still breast feeding. Many women assume incorrectly, they can't conceive while they are breastfeeding. This is not true. I know of many patients who assumed that they were not having a period because they were breast-feeding: when in fact they were pregnant.