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Can Breastfeeding Cause Irregular Periods?

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Can breastfeeding cause irregular periods? Here’s everything you need to know about nursing and how it can affect your cycles!

If you plan to breastfeed after birth, there will be a lot to learn, like how to get the proper latch; how to establish a good eat, play, sleep schedule; and where to find the best breastfeeding essentials. Don’t be afraid to ask as many questions as you need to, especially when it comes to your changing body and feeding your baby.

One question you may have as a first time mother is “can breastfeeding cause irregular periods?”

The short answer is, yes!

A fortunate side effect of birth is a significant break from any visits from Aunt Flow. Most mothers will go at least 6 months before experiencing their first postpartum period. But as hormone levels change and adjust, your period will sneak back in. It may also look and feel different than what you’re used to.

So, let’s dive into some specifics.

Below you’ll find information about how breastfeeding affects your hormones, when and what to expect after your period returns, and when you’ll likely experience a normal period and normal cycle.

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Breastfeeding and Hormonal Changes

Pregnancy is replete with hormonal changes that aid in preparing the body to give birth and stimulate milk production. You may have heard of the hormone, prolactin. This hormone, released by the pituitary gland, is responsible for breast milk production.

Breastfeeding mothers also experience specific hormone changes in response to the physical act of nursing.

Regular breastfeeding keeps prolactin levels high which prohibits the release of other hormones that enable your body to experience a new pregnancy (i.e. menstrual periods). This is known as lactational amenorrhea.

This phenomenon is unique to each mother and baby and can last for just a few months up to a few years. There are several factors that play into how soon your period will return.

Things like:

  • How frequently your baby feeds
  • Whether your baby takes any kind of supplements
  • If your baby takes a binky or pacifier
  • Your newborn’s sleep cycle
  • The introduction of solids to your baby’s diet
  • Your unique body chemistry and sensitivity to hormones

As your baby gets older and feeds less, this will signal the pituitary gland to produce less prolactin and your period may begin again, though you’re still technically breastfeeding.

Irregular Cycles while Breastfeeding

Three menstrual pads with varying amounts of small red beads on light blue background.

Your first period while breastfeeding may look and feel a lot different than what you’re used to. But don’t worry, irregular periods are completely normal during this time.

The same hormones that were responsible for blocking your regular flow may affect how much and how often you bleed once you start up again. Your own hormonal balance prior to breastfeeding may also affect how your cycle functions while nursing.

It’s normal to experience spotting, lighter periods than normal, and even missed periods from time to time that can stretch several months. Alternatively, your period may also be heavier and more painful than you’re used to. There’s no way to predict exactly how breastfeeding will affect your period and this can be different from pregnancy to pregnancy.

When will your normal cycle return?

A normal cycle can take a while to return. Again, this will depend on your particular body and your baby. Most non-lactating women will get their normal period within a couple months after birth. For women who do breastfeed, there can be a lot of variability and irregularity that can last the duration of your breastfeeding experience.

Once breastfeeding has ended, if you haven’t already resumed a normal cycle, you should get back into your pre-pregnancy rhythm pretty quickly.

Can your period affect milk production?

Four full breastmilk storage bags standing upright in freezer shelf.

You don’t have to give up breastfeeding just because your period returns. In fact, mothers are encouraged to nurse for at least a full year if they are mentally and physically able. While not serious, you should note that your milk supply can be affected by your menstrual cycle.

Changes aren’t typically drastic or long-lasting. You might see a slight reduction in milk production during this time and your baby might be a little fussier. Be prepared to nurse more often to compensate for shorter nursing sessions.

Your production should return to normal once your period ends. If you have concerns about decreased milk supply, consider taking calcium and magnesium supplements to minimize reduction.

When to Seek Medical Advice

While irregularity is normal during breastfeeding, you should still keep an eye out for certain changes, like excessive heavy bleeding (frequently soaking through pads), longer than normal periods, severe pain, or large clots.

Talk to your doctor if you have any concerns or experience any of the symptoms above. Your doctor can help to rule out health problems like:

  • Uterine fibroids (noncancerous cells on the uterus)
  • Extreme weight loss
  • Ovarian cysts or polycystic ovary syndrome (PCOS)
  • Pelvic inflammatory disease

Birth Control Options

You should also reach out to your healthcare provider to seek advice about the best birth control options and whether or not to use hormonal birth control. Many women use breastfeeding as a form of birth control, and while this isn’t a 100% reliable form of birth control, once your period starts you’ll need to find other means.

If you want to continue breastfeeding, be sure to work with your doctor to find the best option for you and your nursing baby.


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Is ovulation irregular while breastfeeding?

Not only can breastfeeding cause irregular periods, but it can also affect ovulation. It’s normal to have inconsistent cycles while breastfeeding and that includes ovulation. Be on the lookout for signs of ovulation like elevated basal body temperature and mood swings.

How long does it take for the menstrual cycle to regulate after breastfeeding?

This can vary from woman to woman, but a woman’s cycles will generally regulate by the 6th full cycle after fertility returns. There may also be a relationship between regularity and the timing of when the first period occurs.

Women who start having periods earlier on in their breastfeeding may have longer-lasting irregularity and those who resume their periods further into their journey may return to a normal cycle more quickly. And some women may not have a regular period until after their baby is fully weaned.

Has anyone got pregnant while breastfeeding?

Yes! It is possible to become pregnant while breastfeeding. When your period returns that means you are fertile.

Though you may not experience a regular period while breastfeeding, that doesn’t necessarily mean a lack of ovulation. Ovulation takes place mid-way through your cycle, so you can ovulate without actually having a period.

Want More?

Looking for more information on breastfeeding? Check out these 40 breastfeeding tips and these 20 important things to know about breastfeeding. And you can also utilize your hospital’s lactation consultant if you choose to give birth in that setting.

Here are some other great motherhood resources new moms need:

Your Turn

Now that we’ve answered the question, “Can breastfeeding cause irregular periods?”, let me know what other breastfeeding inquiries you may have or any helpful tips you think I should add!

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