For most people who menstruate, pain and other menstrual symptoms are an expected part of each month—but for people with endometriosis, those symptoms are often debilitating.

Endometriosis affects an estimated 190 million women worldwide. The condition happens when tissue similar to the kind that lines the uterus—called endometrium—grows outside of the uterus, usually on the ovaries, fallopian tubes, or on the outside of the uterus.

During a typical menstrual cycle, the tissue that lines the uterus builds up and then sheds—it’s what contributes to the pain felt as period cramps.

With endometriosis, the same thing happens, but when the build-up and shedding of tissue happens outside of the uterus, it causes inflammation, pain, swelling, and scarring in those areas.

Because it’s often misidentified as period pain, endometriosis is hard to catch and diagnose. Here, an ob-gyn and a reproductive medicine specialist help identify five signs your period pain and other symptoms are actually signs of endometriosis—and how to cope.

Some cramping or discomfort during your period can be expected.

“This is because your uterus is made of muscle and is working to squeeze fluid, or the blood during menstruation, out of the uterus,” Asima Ahmad, MD, Chief Medical Officer and co-founder of Carrot Fertility, and a double-board-certified ob-gyn, told Health.

However, severe or debilitating pain during your period is not normal. 

“Women and teenaged girls are generally taught that menstrual period cramps are supposed to hurt,” Albert Hsu, MD, fertility specialist and IVF Medical Director at UC Health, told Health. “However, menstrual periods should not cause such terrible cramping pain that you cannot go to work or school.”

Experts say if you experience severe pain during your period—enough to interfere with your daily activities—it’s important to get evaluated by a doctor.

Although pain associated with endometriosis typically shows up around menstruation, it’s not the only time.

People with endometriosis can experience pain while ovulating, having a bowel movement, or during urination.

The type of pain associated with endometriosis outside of menstruation may also feel different than period cramping—some people describe it as a stinging or burning sensation, while others say it feels sharp or throbbing. The pain may also radiate to other areas of the body, like the stomach, back, or legs.

Feeling pain during sex—known medically as dyspareunia—can be caused by a variety of things, including insufficient lubrication, vaginismus, and fibroids. It can also be a sign of endometriosis.

“Many times, people will think [pain during sex] is just a lubrication or positional issue, but it’s important not to ignore a recurring pattern,” said Hsu.

If you’re routinely having painful intercourse, Hsu said to take note of what kind of pain is occurring—whether it’s sharp, dull, or throbbing—and pay attention to when the pain occurs, such as with penetration or around the time of your period.

“[Those] things alongside potential imaging and examination will help your doctor determine what the cause of the pain may be,” Hsu said.

A woman or person assigned female at birth is considered infertile when they can’t get pregnant after 12 or more months of regular, unprotected sex. Similarly, undergoing fertility treatments unsuccessfully can also signal infertility. Endometriosis may be to blame.

“This is because endometriosis can cause infertility by affecting the egg or embryo quality, the fallopian tubes, the endometrial (uterine) lining and causing scarring or altering the anatomy of the pelvis,” said Ahmad.

Not everyone with endometriosis will have infertility, said Ahmad, but the condition increases the risk and may be able to explain infertility without a known cause.

“In some cases of unexplained infertility,” said Ahmad, “sometimes a laparoscopy can reveal undiagnosed endometriosis as being the cause of infertility.”

On the flip side, becoming pregnant may tamp down symptoms of endometriosis. According to Ahmad, the hormone progesterone becomes elevated during pregnancy, which can suppress endometriosis symptoms.

But that’s temporary. “Once pregnancy is over, your progesterone level drops, and symptoms can return,” said Ahmad.

Fatigue isn’t generally considered a classic sign or symptom of endometriosis.

“However,” said Hsu, “I have had a number of endometriosis patients who are simply exhausted by the toll of endometriosis-associated pain and/or endometriosis infertility.”

Some research points to a link between fatigue and endometriosis, too: A 2022 study published in the journal In Vivo found that chronic fatigue syndrome may be among the main symptoms of endometriosis, along with dyspareunia and bowel disorders. 

Though more research is needed on the link, Hsu said that the burden of missing school or work because of excruciating and debilitating pain symptoms, as well as the stress and anxiety associated with infertility and poor pregnancy outcomes, can lead to poor sleep quality and fatigue.

Endometriosis is typically diagnosed with surgery, which can be done through laparoscopy, a minimally invasive procedure that allows a surgeon to examine the abdominal or pelvic organs through small incisions.

According to Ahmad, doctors may suspect endometriosis based on reported symptoms or imaging, “but the gold standard for definitive diagnosis is surgical visualization, removal of endometriotic implants, and histological confirmation.”

“Unfortunately, for many women, it can take years—an average of 7.5 years—to be diagnosed with endometriosis,” said Ahmad. “And sometimes with that delay in diagnosis, the condition can worsen and cause inflammation, invasion or scarring of tissue.”

However, doctors don’t need to wait for surgical confirmation to start treating endometriosis, said Ahmad.

First-line treatments for pain associated with endometriosis include contraceptives (combination birth control pills, progestin-only birth control pills, and IUDs) and medications that help alleviate pain. For infertility associated with endometriosis, in vitro fertilization (IVF) is an option.

According to Ahmad, surgical interventions may further reduce symptoms. That could involve removing lesions or other tissue damaged by endometriosis or a hysterectomy, in which all or part of the uterus is removed.

“Everyone’s journey will be different,” said Ahmad, “so the right way to manage endometriosis for you should be discussed with your doctor.”