Can You Get Pregnant While Breastfeeding?

Blog

Apr 10

Something that causes a lot of confusion is trying to get pregnant while breastfeeding, or maybe even trying not to get pregnant while breastfeeding, especially when fertility treatments are involved. We’re going to talk about how breastfeeding impacts your hormones, fertility, and when it might be time to wean if baby #2 is something you’re thinking about.

Yes, You Can Get Pregnant While Breastfeeding

Let’s get this out of the way first—you absolutely can get pregnant while breastfeeding. Even if you’re exclusively breastfeeding, it’s not a 100% effective birth control method. It’s not super common, but it’s possible.

So what’s happening? This has to do with something called lactational amenorrhea. Basically, when you’re nursing a baby who is under six months old and you're their sole source of nutrition (and you're breastfeeding directly—not just pumping), your brain is pumping out a hormone called prolactin.

Prolactin is made by the pituitary gland and helps your body make milk. But it also does something else—it suppresses the production of FSH and LH, the hormones that tell your ovaries to ovulate. If you’re not ovulating, you’re not getting pregnant.

How Prolactin Affects Ovulation

Your pituitary gland is this little powerhouse hanging under your brain—picture a punching bag on a string. Different sections release different hormones. When the prolactin section is working overtime (like when you're nursing), it takes up the blood supply and action from nearby areas, including the one responsible for FSH and LH.

As prolactin levels rise, ovulation decreases. And what’s fascinating is that this doesn’t happen all at once. It’s a spectrum of ovulatory dysfunction:

Stage 1: Your cycles get shorter because the luteal phase (the second half of your cycle) gets shorter.
Stage 2: Your cycles get longer and more irregular—you're taking longer to ovulate.
Stage 3: No periods at all—amenorrhea.

So if you’re feeding your baby three times a day or more, there’s a good chance you’re still in that amenorrhea stage and not ovulating. But that doesn’t mean you're in the clear—ovulation happens before your first period, so you might not even know you’re fertile again until it’s too late.

When Will Your Period Return?

On average, ovulation returns somewhere between 6 to 12 months postpartum, especially once your baby starts getting nutrition from other sources. As prolactin naturally drops, FSH and LH start waking back up, and ovulation may return.

But just because your period is back doesn’t mean things are totally normal yet. Many people experience short luteal phases or irregular cycles for a while. That means you can get pregnant, but it might take more time—and the quality of ovulation and uterine lining may still be in flux.

Breastfeeding + Fertility Treatments: Should You?

If you’re doing fertility treatments, the conversation changes a bit.

Clomid + Breastfeeding

Clomid actually decreases prolactin, so we worry that it could interfere with milk supply. Also, medications can pass into breast milk, and we always want to avoid anything that could impact your baby.

IVF + Breastfeeding

I don’t recommend doing IVF while you’re still breastfeeding. Not because it’s impossible, but because:

Medications might stop your milk.
Prolactin can thin your uterine lining.
Your chance of implantation and pregnancy could be lower.

Especially if you don’t have many embryos, we don’t want to compromise the outcome by rushing. Your embryos are safe—they’re frozen and waiting. Let's give the baby in your arms everything you've got first.

Can Breastfeeding Cause Infertility?

It doesn’t cause infertility, but it delays fertility. The longer you’re breastfeeding frequently, the longer it might take your cycle to return to normal. If you're still breastfeeding a lot and struggling to get pregnant, one of the first things I’ll talk to you about is gradually reducing feedings—especially if your baby is over 6 months and getting other nutrition.

So… Can You Try to Get Pregnant While Breastfeeding?

You can, but should you? Honestly, I don’t recommend trying to conceive while still breastfeeding, especially not with fertility treatments involved. We want your hormones balanced, your uterine lining thick, your cycles regular—basically, we want your body ready to fully support that next pregnancy.

TL;DR: What You Need to Know

You can get pregnant while breastfeeding—especially if you're not exclusively nursing.
Breastfeeding suppresses ovulation through high prolactin levels.
Your period might not return for 6–12 months postpartum.
If you want to get pregnant, cutting back on feedings can help ovulation return.
Fertility treatments while breastfeeding? Not ideal.
Protect your milk supply and give your next embryo the best chance by waiting.

I hope this helped clear up some of the confusion around this topic. I know it can be overwhelming to think about timelines, babies, and your hormones all at once.