What are the odds of getting pregnant while breastfeeding

Don't Listen To Anyone Who Says You Can't Get Pregnant While Breastfeeding

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A little pregnancy-prevention preoccupied bird might have told you that if you’re breastfeeding, it’s basically impossible to get pregnant even if you have sex without protection. It makes sense—if you recently had a child, your body should do its due diligence and set up a natural baby-proofing mechanism so you don’t accidentally wind up with way more than you bargained for. But that logic isn’t as simple as it seems.

“It’s true and not true,” Jamil Abdur-Rahman, M.D., board-certified ob/gyn and chairman of obstetrics and gynecology at Vista East Medical Center in Waukegan, Illinois, tells SELF. Yes, the very act of breastfeeding suppresses ovulation, he explains. Namely, prolactin, the hormone that stimulates breast milk production, inhibits the FSH hormone that triggers your ovarian follicles to release eggs, he explains. Without an egg available for fertilization, you can't get pregnant, which is aces when you're still adjusting to new motherhood.

But the general thinking is that this only applies to people who are strictly breastfeeding, not those supplementing with other forms of nutrition for their babies. “When you’re only breastfeeding, your body is getting that constant hormonal feedback,” Sarah Yamaguchi, M.D., ob/gyn at Good Samaritan Hospital in Los Angeles, tells SELF. It’s like with birth control pills, she explains: Protection works best when there’s a consistent stream of ovulation-preventing hormones in action. When you miss birth control pills, you're more liable to get pregnant, and your body interprets on-and-off breastfeeding in a similar way, she says.

There’s no concrete rule about how often you need to breastfeed for this protection to kick in. However, most people who breastfeed frequently, around every four hours during the day and every six hours at night, don’t ovulate and won’t get pregnant, Abdur-Rahman says.

But even if that is true for you, it isn’t even in effect for a full year, the experts caution. “If it’s been more than six months postpartum, most people start ovulating again,” Abdur-Rahman says. You might also start ovulating before that but not realize it, which can lead to an accidental pregnancy, Yamaguchi adds. There's this idea that you'll realize you're ovulating because you'll get your period, but that's not how the menstrual cycle works. Once you start ovulating again, an ovary will release an egg, then if there's nothing to fertilize, you'll get your first real postpartum period. “When you have that first ovulation, you have no clue,” Yamaguchi says. So, when you factor in that you’re supposed to wait six to eight weeks after giving birth to have sex again, you only have about four months to enjoy the sex-with-less-chance-of-pregnancy phenomenon.

There are ways to keep tabs on whether you might be at risk of getting pregnant while breastfeeding, like using ovulation kits, monitoring your temperature, which usually gets higher when you ovulate, or checking your cervical mucus, which tends to get thinner at that time of the month, Abdur-Rahman explains. Still, he says, "it's dicey."

Even if you're pretty sure you're not ovulating yet, neither expert thinks breastfeeding alone, even within the first six months, is adequate birth control if you’re having sex but don’t want to get pregnant. “If you’re exclusively breastfeeding and you really don’t want to be pregnant, definitely use something,” Yamaguchi says.

There are plenty of contraceptive options, although Yamaguchi cautions that ones with estrogen can affect milk supply and also put people at higher risk of blood clots for the first few months postpartum, and that IUDs placed in the months after childbirth have a slightly higher risk of expulsion (although it’s still small overall). A chat with your doctor will help you figure out which birth control method is your best postpartum bet.

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