Diagnosing Endometriosis: New Biomarkers Enable Early, Noninvasive Detection

Researchers have discovered novel biomarkers that could allow doctors to detect endometriosis in its earliest stages through a simple blood test. The findings, published in Reproductive Biology and Endocrinology, could help clinicians intervene before the disease causes irreversible damage.

Endometriosis is a gynecologic disease wherein tissue similar to the lining of the uterus grows outside of the uterus. It affects one in 10 reproductive age women and can cause a wide range of often debilitating symptoms, including pelvic pain and infertility. Despite its prevalence and severity, it can take an average of eight to 10 years for adults to receive a diagnosis, and up to 14 for adolescents.

This delay is partly because the gold standard for diagnosing endometriosis is a laparoscopy, a safe but invasive surgical procedure.

Previous research led by Hugh Taylor, MD, Anita O’Keeffe Young Professor of Obstetrics, Gynecology, and Reproductive Sciences at Yale School of Medicine (YSM), uncovered molecular biomarkers—small RNA molecules called microRNAs—in the blood that can help scientists accurately and noninvasively detect endometriosis in adults.

In the latest study, Taylor and his colleagues have now discovered a new microRNA signature in adolescents and young adults that is associated with the early stages of the disease. This finding is critical as over half of patients with endometriosis report first experiencing symptoms in adolescence.

“We finally have a way to detect this disease that is so often ignored and misdiagnosed,” says Taylor, the study’s senior author. “We can prove that these patients have endometriosis in an earlier stage so they can get the treatment they need and get their lives back on track.”

MicroRNAs are found in every tissue and regulate gene expression. Differences in their activity have been linked to nearly every major disease. “They’re like a fingerprint that marks a disease or health state,” says Taylor.

Through examining microRNAs circulating in the blood, Taylor’s team previously discovered microRNAs that are significantly altered in adult patients with endometriosis. In a larger trial of 100 patients, they found that they could use these biomarkers to accurately detect endometriosis through a noninvasive blood draw. Participants on average were in their mid-30s.

In this latest study, the researchers specifically focused on younger patients to identify differences in microRNAs that might be affiliated with earlier stages of the disease.

“We need to diagnose the disease much earlier, because endometriosis often doesn’t start when a person is 25,” says lead author Alla Vash-Margita, MD, associate professor of obstetrics, gynecology, and reproductive science at YSM who specializes in treating children and adolescents. “We have hard data that it commonly starts in adolescence, shortly after the first period.”

The team studied 51 adolescents and young adults (aged 13 to 26) with pelvic pain who were scheduled for gynecologic surgery between 2019 and 2024. Before surgery, the researchers took blood samples from each person and isolated the microRNAs.

The surgeries confirmed endometriosis in 31 of the patients and comparing their blood samples with those not diagnosed with the disease revealed new differences in microRNA expression that were unique to early stages of endometriosis.

“Through future trials, we can and will develop a clinical diagnostic test that can be used for early diagnosis of endometriosis, so people don’t have to undergo major surgery,” says Vash-Margita.

Further studies validating the findings in distinct cohorts will be needed before a blood test could become commercially available. But the researchers are hopeful that noninvasive testing for endometriosis will become available in the coming years.

“It is so important that we come up with early diagnostics and distinguish this disease early on before it goes on to cause debilitating pain,” says Taylor. “The earlier we can diagnose it, the faster we can restore people’s lives.”