Endometriosis can elude diagnosis for years. What to know about the disease and new ways to find it

When Zoë Armstrong got an ultrasound report showing signs of endometriosis , she called her mom and cried. After years of suffering and seeking help from doctors, she finally had an answer.

“To see it on paper, I was like, ‘I’m not crazy,’” the 31-year-old recalled. “I very much knew what I was feeling in my own body.”

Armstrong’s experience is not unusual. The American College of Obstetricians & Gynecologists says people can wait a decade or more after the onset of symptoms to receive a diagnosis of endometriosis. The painful condition , which causes tissue similar to the lining of the uterus to grow on other parts of the body, afflicts 1 in 10 women worldwide.

New tests being used in other countries aim to help address the issue. And while they’re raising hopes among doctors and patients, they’re not currently available in the U.S., and some experts expect them to be a useful tool but not a complete solution.

Research suggests endometriosis is a type of chronic inflammatory disease. The exact cause is unknown, although experts say genetics plays a part.

Symptoms vary depending on the extent of the disease and where the tissue appears. Usually, it’s found on organs such as the bladder, bowel or ovaries, but in rare cases it can even be outside the pelvis. Symptoms may include bloating, fatigue and infertility – and most commonly pain that can strike during periods , intercourse and bowel movements.

“It can be debilitating pain that makes you not be able to go to school or work or be in bed for days at a time,” said Dr. Drorit Or at Mount Sinai West in New York.

Armstrong’s first symptoms, at age 11, were stabbing pains on her left side that repeatedly sent her to the school nurse. As an adult, she was also wracked with severe pain as well as nausea, heavy periods, acne and rupturing ovarian cysts.

Shortly after getting married a couple of years ago, she experienced pain she likened to having a tiny fencer inside her “just stabbing me incessantly for hours at a time.”

Armstrong was finally diagnosed at 29 by a doctor who also had the disease.

An ultrasound found an endometrioma, a fluid-filled cyst. She Googled the word, which is when she first cried with her mom. She also cried when a nurse diagnosed her verbally and when surgery formally confirmed the diagnosis.

One reason diagnoses can take so long, experts said, is that patients and doctors often normalize period pain. Symptoms also can overlap with those of other conditions, and not all health care providers have knowledge or expertise in endometriosis, said Dr. Megan Billow at the Cleveland Clinic.

One helpful step patients can take, Or suggested, is to keep a diary tracking when pain occurs, where it’s located and how intense it is.

“Then when you come to the doctor, you come prepared,” she said. “You can definitely ask: Do you think I have endometriosis?”

New diagnostic tests are now available in some other countries, but the U.S. Food and Drug Administration hasn't approved them.

One is a half-hour test called EndoSure, which detects endometriosis by measuring electrical signals in the gut using sensor pads on the abdomen, with results available to the physician afterward. Another, Endotest, analyzes a saliva sample for microRNAs that can indicate whether the condition is present, providing patients with results in two to three weeks.

In the United Kingdom, an institute that provides national health advice recently published draft guidance recommending both be used by the National Health Service for three years while more evidence is collected on how well they work. The goal is to speed up diagnosis in primary care .

Dr. Mark Noar, founder of Maryland-based EndoSure, said the company is in the process of submitting its application to the FDA in the U.S., seeking approval for the test to be used as an aid to help doctors make the diagnosis.

Meanwhile, the French company Ziwig is taking final steps to make Endotest available to U.S. patients through another pathway that allows lab-developed tests to be made available through certain certified laboratories without FDA approval. Ziwig's Dr. Andrew Spiers said the diagnostic test is a starting point. Once the doctor knows there's endometriosis, he said, that would be the time to do imaging if it hasn't already been done.

“I would not say that it’s the only tool that a patient would have in their diagnostic pathway,” Spiers said.

U.S. doctors agree that such tests wouldn’t replace other diagnostic tools and methods, but may be helpful. One thing they won't do, however, is solve the persistent problem of normalizing period pain.

Armed with a diagnosis, women can work with their doctors on treatment plans.

Treatments for endometriosis pain include pain relievers such as ibuprofen and a prescription medicine specifically for endometriosis; hormone therapies such as birth control pills, progestin therapy and medications that cause periods to stop temporarily; and surgical treatments including hysterectomy in some severe cases.

Armstrong underwent excision surgery, a procedure to remove endometriosis lesions and scar tissue. She said she still sees about three doctors a week for pelvic floor therapy and other issues. She also visits middle and high schools around New York City with the Endometriosis Foundation to educate students.

“They need to know what to look out for — not just for endo, but for other women’s health conditions in general,” she said.

Or, the Mount Sinai doctor, said young women should know there's help available — and hope.

“You don’t have to live in pain,” Or said. “You can have a very, very good life managing this disease.”

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