It’s no secret that having your period can come with uncomfortable and annoying symptoms like bloating, frequent trips to the bathroom, a constant tummy ache, and painful cramps. But for people with irritable bowel syndrome (IBS), the symptoms can be even worse, from the start of your monthly period and throughout the cycle.

The reason could be the link between the gut and the way the reproductive system functions during a menstrual cycle. Read on to find out how your IBS symptoms can affect your period.

The Gut and the Reproductive System Influence Each Other

According to Olubunmi Oladunjoye, MD, MPH, a general internist and assistant professor at Baylor College of Medicine in Houston, the gut contains receptor cells for the female sex hormones estrogen and progesterone. So, changes in those hormone levels may impact how well the gut functions.

An article published in Gut Microbes in 2021 noted that the gut microbiota — all of the microorganisms in the gut — coordinates the activities of the reproductive system by interacting with sex hormones such as insulin, estrogen, and androgens.

Research also shows that excess harmful gut bacteria (dysbiosis) may increase estrogen levels by preventing the liver from breaking down excess estrogen. According to the Cleveland Clinic, high estrogen causes tumor-like cell overgrowth along the uterine lining, resulting in pain and conditions such as endometriosis.

And that’s not all. Disrupting the gut microbiome balance can also play a role in cancers, pregnancy complications, and disorders like polycystic ovarian syndrome, among other reproductive-related conditions. But, as the authors of the Gut Microbes article state, research is lacking on exactly how the gut and the reproductive system interact in that way.

The link between the gut and reproductive health is “essentially a control or balance of estrogens and progesterones,” says Rudolph Bedford, MD, director of gastroenterology at Providence Saint John’s Health Center in Santa Monica, California. He adds that estrogens, in particular, can “control and cause a variety of situations within the gastrointestinal tract.”

Using estrogen as an example, Dr. Bedford explains how female sex hormones interact with the gut microbiome: The liver deactivates active estrogen that been transported from the ovaries. This deactivated estrogen then exits the liver through the bile and moves to the small intestine, which is home to the microbiome. The gut bacteria produce an enzyme that interacts with the estrogen before it gets excreted. But if the microbiome gets interrupted, the estrogen may not metabolize properly. Instead, it may return to the bloodstream, eventually causing digestive issues such as constipation and bloating.

Bedford believes that the excess circulating estrogen and progesterone caused by dysbiosis may also result in heavy periods, uterine fibroids, breast cancer, and painful periods (dysmenorrhea) alongside altered bowel habits.

How Do Menstrual Cycles Impact Gut Health?

It all comes down to hormones. During your period, hormones affect more than just your mood and energy levels — they can also boss your digestive system around.

Sex hormones fluctuate during different phases of the menstrual cycle, explains Dr. Oladunjoye. ”Estrogen is usually at its peak just before ovulation, while progesterone is at its peak during the luteal phase — the phase between ovulation and the onset of menstruation. But these hormones drop to the lowest levels just before the period begins.”

Both estrogen and progesterone control smooth muscle contractions in the intestines, affecting how quickly food travels in the gastrointestinal (GI) tract. "During menstruation, some women tend to have abdominal pain, and some have diarrhea,” she says.” Many of these GI-related disturbances are linked to the actions of female sex hormones.”

Oladunjoye also notes that when progesterone is at its peak during the luteal phase, it usually causes constipation.

Also, every month before your period, your body releases natural chemicals known as prostaglandins, which play an essential role during your cycle. They trigger the muscles in your uterus to contract, making it easier to shed the uterine lining. The bad news is that these prostaglandins can have the same effect on your bowels. The result? More frequent poops and even diarrhea.

In a nutshell, the hormones associated with your period interact with your gut to cause a variety of symptoms. With IBS, the symptoms can be significantly worse, according to the International Foundation for Gastrointestinal Disorders.

What’s the Link Between IBS and Your Period?

Again, hormones appear to play a role in aggravating IBS symptoms. “Estrogen and progesterone inhibit the smooth muscle contractions in the intestines, which adversely affects gut motility and may be the cause of heightened IBS symptoms during periods,” says Oladunjoye.

In a study published in Cureus in 2021, more than half of the participants with IBS had bloating during all phases of their menstrual cycle. The study also found that premenopausal IBS patients had more symptoms during their period that affected daily activities and lowered their quality of life than they did during other cycle stages.

In a study published in Neurogastroenterology Motility in 2021, postmenopausal IBS patients had more severe symptoms than premenopausal patients did. The study also compared men (who don’t menstruate) of similar ages and found no age-related changes in symptom severity. The results suggest that lower levels of female sex hormones — especially estrogen and progesterone — may affect the brain-gut interaction and heighten IBS symptoms.

There’s evidence, too, that low sex hormone levels could also be behind the increased severity of pain and GI symptoms in IBS patients during their monthly cycle. Estrogen affects how the body uses the feel-good hormone serotonin, which raises your pain threshold to help you manage pain such as period cramps. If you experience terrible cramps at the beginning of your cycle, a dip in estrogen levels may be the culprit.

As female sex hormone levels drop, cramps and GI symptoms such as constipation, bloating, and bowel movements increase. People with IBS already suffer from the GI symptoms associated with periods, so when that time of the month arrives, the severity of these symptoms goes through the roof.

How to Ease IBS Symptoms During Your Period

When it’s that time of the month, Oladunjoye recommends treating your IBS symptoms the same way you would treat them at any other time. She suggests you:

Avoid trigger foods, such as fried foods, that could set off your symptoms, especially during your period.
Eat more foods containing soluble fiber.
Steer clear of gas-inducing foods like beans, broccoli, Brussels sprouts, and cabbage, as they increase bloating, particularly during your period.
Drink plenty of water.
Exercise regularly.
Get quality sleep.
Keep up with your IBS medications as prescribed by your physician.
Seek medical care to ensure a proper diagnosis and adequate treatment if your symptoms prevent you from performing your daily activities.

Caring for Your Gut and Reproductive Health

Maintaining the interplay between the sex hormones and the gut microbiome will promote gut-reproductive health, says Bedford, and improve period experiences. He notes that a healthy microbiome is important for a healthy reproductive system; it encourages the proper metabolism of sex hormones, which prevents the onset of digestive disturbances.

To keep your gut and reproductive health in tip-top shape, try these tips:

Stay physically active — from walking to lifting weights, the key is to keep moving. If you’re too busy and can’t get to the gym, Oladunjoye says at-home workouts can be just as effective. Here’s how you can get started.
A healthy, balanced diet is essential. Oladunjoye maintains that what we feed our gut can affect our reproductive health (and health overall). Include lots of fruits and vegetables in your diet, as they promote quality bowel movements. But keep in mind that certain fruits and vegetables can be hard to digest for some people. If that happens, it’s a good idea to see your doctor or a nutritionist to work out a food plan. And if getting enough fiber from food alone is challenging, Oladunjoye says taking a supplement could be helpful.
Consider taking probiotics, Bedford suggests. (Note: According to American Gastroenterological Association guidelines, there isn’t enough evidence to support the use of probiotics to treat IBS.)
Cut back on drinking alcohol, and don’t overdo it with caffeine either.
Try to manage and reduce stress.