Some studies suggest that HRT may increase your risk of developing ulcerative colitis (UC). Other research has found that people with UC can safely take HRT. But more research is needed.

Hormone replacement therapy (HRT) is a treatment primarily used to relieve symptoms of menopause. Symptoms that disrupt health and quality of life, such as sleep disturbances and hot flashes, could warrant the use of HRT.

While the Food and Drug Administration has approved HRT for menopause treatment, these medications are not right for everyone. For example, they may not be ideal for people with or at risk of ulcerative colitis (UC).

UC is a form of inflammatory bowel disease (IBD), a group of chronic conditions known for causing intestinal inflammation and ulcers. Common symptoms of UC include chronic diarrhea, abdominal pain, and problems with bowel movements.

More clinical studies are necessary to explore the possible link between HRT and the development or worsening of UC, but the current body of research suggests that such a link is possible. Here’s what the science currently says about HRT and UC and why you may need to proceed with caution.

The exact cause of UC isn’t known, but experts think it’s due to a combination of:

Some researchers have also looked into the possibility that HRT could increase the risk of developing UC. In one large cohort study published in 2012, researchers linked an increased risk of UC with HRT use based on results from 108,844 participants.

While more studies are needed, the authors of this landmark study suggested that estrogen pathways might explain the risk of UC from HRT use.

It’s also unclear whether HRT is safe for everyone with UC.

In a 2018 study involving 1,203 people with IBD, researchers found that the participants’ symptoms fluctuated along with their hormone levels. Factors that influenced these hormone fluctuations included:

Of the 93 participants using HRT, 61% said their symptoms had not changed. Another 31% said they weren’t sure whether their symptoms had changed. None of the participants said their symptoms were worse after taking HRT.

More studies of this nature are necessary to specifically explore HRT’s influence on UC and whether HRT negatively affects the symptoms and course of IBD.

Inflammation is an underlying factor in UC development. At the same time, UC-related inflammation may negatively affect your natural hormone levels.

While HRT may have a link to UC, research suggests that estrogen may protect against inflammation.

A 2020 review suggests that perimenopause and menopause may increase body inflammation, while estrogen may help regulate it.

Research has not found that UC negatively affects menopause. But it’s possible to experience an improvement in UC symptoms after menopause.

This is especially true in people who might have previously experienced symptom flares around their menstrual cycles. In a 2018 study, about half of menstruating people with UC reported worse symptoms during their period due to hormone fluctuations.

Interestingly, UC may also affect the time at which menopause starts. In a 2022 study, researchers found that people assigned female at birth with IBD experienced menopause an average of 1.5 years sooner than those without IBD. The reasons for this were not clear.

You may want to discuss the following information about HRT, estrogen, and IBD with a doctor.

Does HRT increase your risk of Crohn’s disease?

Crohn’s disease is a type of IBD that affects both your large and small intestines. The 2012 study on HRT mentioned above found that HRT use increased the risk of UC but not Crohn’s disease. More research is needed to find out why.

What medications should be avoided with ulcerative colitis?

Certain medications, including antibiotics and nonsteroidal anti-inflammatory drugs, are known to cause UC flares. If you need these medications, talk with a doctor about the correct doses and how long you should take them.

Can estrogen help ulcerative colitis?

Some research suggests that estrogen may actually help UC. But, as one 2021 review notes, the benefits are primarily seen after menopause. Furthermore, estrogen spikes during pregnancy may worsen UC symptoms.

While a doctor will help you weigh the overall benefits against the possible risks of HRT, UC is another important consideration. This may be true whether you currently have UC, have a family history of IBD, or have other risk factors for developing this condition.

Current research suggests a possible link between HRT and UC. However, estrogen itself may have other benefits, such as reduced inflammation. More studies are certainly needed.

In the meantime, you can work with a doctor to decide whether HRT is the best fit for you or whether other treatments might be safer.