Is It Possible to Get Pregnant While You're Breastfeeding?

If you just recently had a baby, your mind is probably overflowing with a myriad of questions about your new mom life, from how to know whether your baby is getting enough milk to when (or if) you’ll ever score a full night’s sleep again.

One that tends to top the list for most breastfeeding mothers is whether or not you can get pregnant while breastfeeding. You may have heard from a friend that nursing can serve as a form of birth control — and while that’s not entirely untrue, it’s not the whole story either.

Can you get pregnant while you’re breastfeeding?

The simple answer is yes. Although breastfeeding offers some protection from ovulation, the monthly occurrence where you release a mature egg from one of your ovaries, it is possible to ovulate and become pregnant prior to getting your first period.

The key players here are the hormones oxytocin and prolactin, which are responsible for milk production and the let-down reflex. Increased levels of these hormones actually suppress the brain from making the main hormone that stimulates the ovary to grow an egg each month. When a mother is breastfeeding exclusively, or even on a consistent basis, it is less likely that she is going to ovulate at all until she starts to wean.

That doesn’t mean that you won’t ovulate or conceive. The "protective" effect of breastfeeding becomes progressively less effective the longer it's been since you delivered your baby.  

Can you get pregnant if you’re breastfeeding and haven’t gotten your period yet?

Since ovulation comes before menstruation in your monthly cycle, the absence of your period does not eliminate the chance that you could be ovulating at any given point. In fact, it is most common for you to get a period about two weeks after ovulation.

In other words, if you wait until you get your period to start using other forms of birth control, it may be too late to prevent pregnancy if that’s what you’re trying to do.

Why do people think of breastfeeding as birth control?

Exclusive breastfeeding, which consists of nursing at least every four hours during the daytime and at least every six hours at night, for the first six months postpartum and before the return of your period is referred to as the lactational amenorrhea method (LAM) of birth control. It is considered an effective form of birth control so long as all of the criteria are met.

Breastfeeding outside of those criteria, especially when the mother is supplementing with formula or solids and her period has yet to return, does not offer the same contraceptive protection. For this reason, your OB/GYN will likely suggest that you start another kind of birth control if you're not actively trying to get pregnant.

If you don't want to get pregnant again, it's actually a good idea to speak with your OB/GYN about starting another form of contraception soon after delivery even if you are breastfeeding. Several forms of contraception have no impact on breastfeeding, including progestin-only birth control pills and IUDs.

Can breastfeeding interfere with your pregnancy if you do get pregnant?

It is generally considered safe to continue to breastfeed once you become pregnant. However, some women may experience cramping due to the release of small amounts of oxytocin (the same hormone that causes contractions) during breastfeeding. The concern is that, in rare cases, this can cause preterm labor or possibliy early pregnancy loss.

While this is unlikely, if you are pregnant and breastfeeding you should tell your OB/GYN if you start experiencing regular and/or increasingly painful contractions to rule out any interference with your pregnancy. The most important consideration to make when breastfeeding during pregnancy is to get enough calories to support both your growing fetus and developing child at the same time.

While you certainly can use breastfeeding to your advantage if you’re trying to prevent another pregnancy so quickly, it’s not a fool-proof method, so it's important to be careful. If you follow the rules laid out in the LAM method — exclusive breastfeeding of an infant younger than 6 months old before your period comes back — you have less than a 5 percent chance of getting pregnant. But you shouldn't rely on breastfeeding as a form of birth control, and your safest bet is to use a backup method even if you are nursing.

It's also important to note that doctors advise women to wait a full year and ideally 18 months to get pregnant again because it's the safest and healthiest option for them and their future pregnancies. Getting pregnant earlier than that, especially within the first six months of your previous baby's birth, can increase the risk of complications in the new pregnancy.