What Are Signs of Returning Fertility While Breastfeeding?

A lot of people assume they can’t get pregnant while breastfeeding, especially if their period hasn’t returned. But here’s the truth: 

You can be fertile before your first postpartum period returns. That’s because ovulation comes before a period, not after. So technically, your first postpartum ovulation can sneak up on you, and if you happen to have sex during that fertile window, pregnancy is possible, even if you haven’t had a period yet.

Whether you’re trying to avoid pregnancy or hoping to conceive again, it’s worth knowing how to spot the signs that your fertility might be coming back, without needing to stop nursing.

Exclusive Breastfeeding As Birth Control?

Breastfeeding naturally delays the return of fertility thanks to the hormone prolactin, which suppresses ovulation. If you're exclusively breastfeeding (no bottles, solids, or soothies, including overnight), this can be a pretty reliable form of birth control known as the Lactational Amenorrhea Method (LAM).

But it only works under certain conditions:

• Your baby is under 6 months old

• You're exclusively breastfeeding, including at night

• You haven't gotten your period yet

Once any of those change, especially if your baby sleeps longer stretches, starts solids, or you introduce pumping, the protection drops, and ovulation can return at any time.

So, How Can You Tell If You're Fertile Again?

You know your body best. Most of the signs of fertility are the same as before you had a baby. 

Here are some common signs that you might be in your fertility window:

1. Cervical mucus changes

If you notice clear, stretchy, egg-white-like discharge, that usually means estrogen is rising and your body may be preparing to ovulate.

2. Ovulation pain or cramping

A twinge or ache on one side of your lower belly can signal ovulation.

3. Increased libido

A sudden shift in desire can be a hormonal clue that ovulation is near.

4. First postpartum period

Once your period returns, that’s confirmation that ovulation likely happened about two weeks earlier.

Want to Be Sure? Here’s How to Track It

1. Watch your cervical mucus daily,  it’s the easiest early clue.

2. Try ovulation tests (OPKs), they detect your LH surge and help confirm when ovulation is near.

3. Track your cycle if it’s started again, even if irregular at first, patterns often settle over time.

To sum up: You can be fertile while breastfeeding, even if you haven’t seen your period yet. Whether you're avoiding pregnancy or hoping for another baby, tuning into your body's signals, especially cervical mucus, can give you the clarity you need, without needing to stop nursing.

Download the Lume App

If you’re thinking about trying again, the Lume app (available on iOS and Android) can help you understand your fertility readiness, figure out which supplements might support you, and help you feel a little less alone in the journey.