Pluses: Most women who are not breast-feeding can return to -- or begin taking -- the Pill when they go for their first postpartum checkup.
What You Should Know: The vast majority of birth-control pills prescribed in this country contain a combination of estrogen and progestin. Some clinicians will give nonnursing women a prescription while they're still in the hospital, but advise them not to begin taking the Pill until three to four weeks after they've given birth. The delay is to ensure that any additional risk of blood clotting after delivery will have passed. Other doctors sometimes prefer that nonnursing women wait to take the Pill until after their first postpartum menstrual period, at around six to ten weeks.
If you're breastfeeding, the estrogen released from the Pill can lower your milk's mineral content and also decrease the amount of milk produced. And although there is no evidence so far to suggest estrogen is bad for the baby, the hormone can enter the breast milk and be passed on to your baby. While some doctors do prescribe combination estrogen and progestin pills to nursing mothers, most now believe these women should consider other alternatives until their baby has been weaned.
There is a pill that contains only progestin, which won't affect the quantity or quality of breast milk. Dubbed the "minipill," it must be taken at the same time every day (which can be difficult for new moms) and has a slightly lower effectiveness rate than pills containing estrogen. To be on the safe side, doctors should wait six weeks before putting nursing mothers on this pill, too. Although the evidence is slim, some have voiced concern about progestin's effect on the newborn's liver and kidneys, which may not be able to process the hormone that gets into the breast milk.