I'm Breastfeeding, So Why Have My Periods Started Again?

Is it normal for my periods to start while I’m breastfeeding?

Breastfeeding can delay the return of your periods, especially if you are exclusively breastfeeding your baby. Experts call this ‘lactational amenorrhea’. Feeding your baby stops certain hormones from releasing, which are important to ovulation (Gill 2016). However, when you get your first period after birth depends on how often you breastfeed, whether your baby is sleeping through at night, and whether they’ve started solid foods yet (Gill 2016, HSE 2022, LLLC 2023). It can also vary hugely from person to person (LLLI 2021). While your periods can be delayed for several months, or even years, while breastfeeding, it’s also possible to have a period within a few months of giving birth (Gill 2016).

Advertisement | page continues belowMost people who are fully breastfeeding become fertile and start their periods again between six and 18 months after giving birth (LLLC 2023, LLLI 2021, Yanniarti et al 2023). You're more likely to get your periods back sooner if:

• Your baby is sleeping for more than four hours at a time during the day, or is sleeping for more than six hours at a time at night.
• Your baby has begun to eat solid foods.
• You are supplementing some breastfeeds with formula milk.
• Your baby uses a dummy.
• Your baby is feeding less often during the day, and for less time at each feed.

(HSE 2022, LLLC 2023)

Your periods are less likely to return if:

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• You're feeding your baby on demand.
• Your baby hasn’t started solid food yet.
• You don’t offer your baby a dummy.
• You don’t give your baby supplementary formula feeds.
• Your baby still wakes at night for feeds.

(HSE 2022, LLLC 2023)

 

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When your periods return also depends on the level of the hormone progesterone in your body. If you have lower levels of progesterone, you're likely to get your periods back earlier than people with higher levels (Ingram et al 2004).

Advertisement | page continues belowSo it's possible that you could be breastfeeding around the clock, but still become fertile and start your periods again. While it’s unlikely to happen, it is possible to get pregnant within three weeks of giving birth, even if you’re breastfeeding and you haven’t started your periods (NHS 2024). So, if you don’t want to increase your family again just yet, it’s a good idea to use contraception when you and your partner have sex.

Is it normal to have irregular periods while breastfeeding?

While breastfeeding, your periods may be irregular and unpredictable compared to your periods before having your baby. You might find that they’re longer, shorter, or even absent for several months (Gill 2016).

More breastfeeding advice and information:

• Find ways to help relieve sore breasts.
• How to cope with leaky breasts.
• Sleep and breastfeeding.