What Really Happens to Your Body When You Stop Breastfeeding

From sore nipples to achy upper-body muscles, low libido and intense hunger, your body goes through many changes while breast or chestfeeding.

And just as your body underwent major changes to produce milk, it must also shift gears when your lactation journey comes to an end. It's true: The weaning process can cause its own set of (sometimes unexpected) physical and emotional symptoms.

But being well-informed can help normalize your experience and help you navigate the transition with greater ease.

That's why we enlisted experts to share what really happens to your body when you stop breastfeeding, along with ways to manage some of the more surprising side effects of weaning.

Feeling a little down while weaning? You're not imagining it.

"Just like when you're pregnant or lactating, weaning can lead to fluctuations in your hormone levels" that may affect your mood, says Cindy Rubin, MD, IBCLC, pediatrician and breastfeeding medicine specialist at In Touch Pediatrics and Lactation.

There are two hormones responsible for this shift — oxytocin and prolactin, says Melissa Kotlen, IBCLC, RN, an international board-certified lactation consultant, registered nurse and care manager at Boram Care, a postnatal care center.

These are considered "mothering hormones" because they contribute to a sense of love, calm, contentment and attachment, she says.

When you're breastfeeding, your body produces high levels of oxytocin and prolactin, but while you're weaning, those levels dip. That means many of those amazing feelings may dissipate, too, Kotlen says. It's not uncommon to feel tearful, sad, moody or irritable as a result.

Plus, even if you've chosen to wean, you may still feel grief or sadness that your breastfeeding journey has come to an end, Dr. Rubin says.

Even if your period was fairly regular pre-pregnancy, your monthly cycle may be a little inconsistent while you wean.

"Once again, we've got some hormones at play," Kotlen says. "This time it's estrogen and prolactin."

"During lactation, your estrogen levels are very low and your prolactin levels are very high, both aiding in suppression of your period," she says. "When you wean, though, you're teaching your body that it's OK for those hormones to return to 'normal' levels."

This transition is not always fast or predictable, though. Dr. Rubin says it's "similar to when menstruation begins during puberty — i.e., the first few periods may be 'anovulatory,'" she says. This means that you menstruate without ovulating.

"Anovulatory bleeding is often irregular," Dr. Rubin says. Your period may be heavier or lighter than usual or may last for a shorter or longer amount of time.

For some people, these post-breastfeeding anovulatory cycles can last for a while. But for others, they may start ovulating within their first period (or even while they're still lactating), Dr. Rubin adds.

The intensity of your period symptoms may also shift after weaning. For example, you may feel worse cramping, or you may even notice fewer symptoms of premenstrual syndrome (PMS), according to Penn Medicine.

When you stop breastfeeding, you may notice some changes in your skin, often like you're going through puberty. Your fluctuating hormones can cause some acne, Dr. Rubin says.

"When you wean, the hormones responsible for maintaining milk supply — prolactin and oxytocin — drop, and your progesterone and estrogen begin to rise again," Kotlen says.

But this hormonal shift also causes "an increase in natural oils (sebum) that can clog pores and cause acne, making you feel as though you're reliving your teenage years," she says.

On a positive note, other pregnancy-related skin changes may actually ‌improve‌ after weaning. For example, your stretch marks may lighten, and your areolas and nipples (which may have darkened and/or grown larger) will usually return to their original appearance, Kotlen says.

Breastfeeding takes up a lot of energy, which can make you feel exhausted, Dr. Rubin says. In fact, your body burns anywhere from 500 to 700 extra calories per day while you're nursing, per La Leche League International.

But weaning can lead to fatigue, too.

As your progesterone and estrogen levels begin to normalize, you might feel very tired, Kotlen says. "Some people even say they feel dizzy," she adds.

Plus, you might also be adjusting to a new sleep schedule, Kotlen says. Your body may still wake you up at 3 a.m. for a middle-of-the-night feeding session even once you've stopped nursing.

When you stop breast or chestfeeding, you don't automatically stop making milk.

In fact, "milk production can continue for many months after weaning," Dr. Rubin says.

Think of it like this: "Your body had to learn to produce milk, and now it has to learn to let go of it," Kotlen says. "Every body is on its own timeline: Some start the weaning process and milk is dried up within days, while others are still hanging onto milk a year later," she adds.

People who produced an overabundance of breastmilk also tend to take a bit longer to dry up their supply, Kotlen says.

And "if you're frequently stimulating your nipples or hand expressing 'just to check' if you're still making milk, you will likely continue to make milk," Dr. Rubin adds.

That's because nipple stimulation and hand expression send signals to your body that it needs to continue to produce milk, she says.

Feeling feverish while weaning? "Fluctuating hormones can sometimes cause chills and sweats," Dr. Rubin says. (It shouldn't cause a true fever, though.)

But "if you're feeling flu-like symptoms along with breast engorgement or have distinct areas of swelling or discomfort in your breasts, you may have mastitis," Dr. Rubin adds.

Mastitis is a "breast infection that can happen during or after weaning, as your body may hold onto milk and not release it (aka, milk stasis)," Kotlen says.

This stagnant milk inside your breast can quickly become an ideal environment for bacteria to breed, according to the Mayo Clinic.

Again, "symptoms include feeling like you have the flu (think: extreme tiredness, aches and chills) and running a high-grade fever (102 degrees Fahrenheit and above)," Kotlen says.

Breast redness, tenderness and lumpiness are all telltale signs of mastitis, too, she says. Your breasts may even feel warm to the touch.

Just as the risk for mastitis increases with weaning, so does painful engorgement and clogged milk ducts, Kotlen says.

Engorgement happens when milk isn't emptied from your breasts, and fluid and blood collect in your tissues, resulting in swelling, tightness and an increase in breast size, according to the Children's Hospital of Philadelphia.

Your breasts may feel hard, full, warm, tender to the touch and may even throb or ache with pain.

Clogged milk ducts can also happen if your breasts are full for long periods of time, Dr. Rubin says. Your ducts are not truly "clogged," but just get narrower due to inflammation, Kotlen adds.

Engorged breasts and clogged ducts are more common at the start of your lactating journey as your body adjusts to its new job of making milk. But these problems can return again when you're weaning.

That said, "some amount of engorgement is expected and is a necessary part of the weaning process," Dr. Rubin says.

In short, because you're no longer feeding your baby, milk stays in your breasts, which can be uncomfortable.

During breast or chestfeeding, some people feel a lull in libido.

That's because your estrogen levels are very low while lactating, which can contribute to vaginal dryness and decreased sexual desire, Kotlen says. Couple this with the exhaustion of taking care of your baby day and night, and sex often becomes low priority, she adds.

"The good news is that, after weaning, estrogen levels rise again, and libido will return," Kotlen says.

Of course, every person is unique. Some folks continue to have a high sex drive throughout their lactation journey while others still don't feel ready for intimacy after weaning. Both are totally natural.

What matters most is how you feel about your libido. As long as you're content, it's not important whether your sex drive is high or low.

People who breast or chestfeed often feel very hungry. As mentioned, "our bodies require about 500 extra calories while we're lactating," Dr. Rubin says. That means you may need to eat a little more to maintain your milk supply.

But as you wean, your caloric needs will lessen. "This can lead to changes in appetite and fluctuations in weight," Dr. Rubin says.

For example, if you're still in the habit of eating an extra snack each day, you might put on a few pounds because your body no longer needs the additional calories.

The changes your body goes through while weaning can be unexpected and sometimes uncomfortable.

Knowing what to expect before you stop breastfeeding can help you prepare for the transition. Still, it's OK to need a little assistance along the way.

If you have any questions or concerns about your weaning process, talk to your ob-gyn, midwife or an international board-certified lactation consultant (IBCLC). IBCLCs are great resources throughout your breast or chestfeeding and weaning journey.