A specific blood test measuring androgen profiles could soon diagnose endometriosis without invasive surgery, according to a case-control study published in the European Journal of Endocrinology. Researchers at the University of Edinburgh found that women with endometriosis exhibit distinct hormonal patterns—notably elevated levels of 11-oxygenated adrenal androgens—that differentiate them from healthy controls. This discovery offers a potential pathway toward a reliable, non-invasive diagnostic test for a condition that currently requires surgical confirmation and years of patient delay.
The Long Path to Endometriosis Diagnosis
Patients typically wait between 4 and 11 years from the onset of symptoms to receive a definitive endometriosis diagnosis, according to Dr. Katie Cameron, a reproductive endocrinologist at the Johns Hopkins University School of Medicine who was not involved in the study. During this prolonged window, symptoms often worsen and severely diminish patient quality of life. Historically, research has focused primarily on estrogen as the primary driver of the disease, leaving the role of androgens largely underexplored.
To investigate whether a broader panel of hormones could improve detection, the research team analyzed blood samples from 159 women with surgically confirmed endometriosis and 57 healthy controls. Led by Dr. Douglas Gibson of the University of Edinburgh, the study measured both classical and 11-oxygenated androgens. The findings revealed a unique hormonal signature associated with the disease that does not appear in healthy individuals.
Distinct Androgen Profiles as Biomarkers
Women with endometriosis demonstrated significantly higher blood concentrations of several androgens, including testosterone. The most statistically significant marker was 11-cetotestosterona, an 11-oxygenated androgen found in elevated levels regardless of the disease stage. When investigators incorporated all androgen markers into a diagnostic model, it achieved an area under the curve of 0.99. A simplified version of the model successfully identified more than 95% of patients within a blinded test subset of the study cohort.
These results prompt a reexamination of endometriosis as an androgen-dependent disorder. However, these conclusions contrast with an earlier genetic study led by Marija Gjorgoska, which associated higher androgen levels with a lower risk of endometriosis. Dr. Gibson attributed the discrepancy to methodological differences, noting that the prior study estimated lifelong exposure using genetics, whereas his team measured direct hormone levels in diagnosed patients.
Validation Hurdles in Clinical Translation
While a non-invasive blood test would transform clinical care, experts emphasize that significant hurdles remain. Dr. Cameron noted that the data currently stem from a single study center focusing predominantly on a European population. Before clinical implementation, the test requires rigorous validation across diverse cohorts encompassing varied age groups, ethnicities, menstrual cycle phases, and concurrent hormone treatments.
Additionally, a validated diagnostic tool must reliably distinguish endometriosis from other origins of chronic pelvic pain rather than simply separating patients from healthy volunteers. Many previously promising biomarkers have faltered during this rigorous validation phase.
Reconsidering Danazol and Future Therapeutics
The findings also revive interest in danazol, an older androgen-derived medication approved for endometriosis that is rarely prescribed today due to adverse side effects such as weight gain, acne, voice changes, and unwanted hair growth. Rather than acting strictly as an added androgen, the researchers hypothesize that danazol functions by suppressing the body’s intrinsic production of the very 11-oxygenated adrenal androgens linked to the condition.
Investigating alternative delivery methods, such as vaginal administration, could minimize adverse side effects, though formal clinical trials remain necessary. Dr. Cameron agreed that danazol’s limitation lies in tolerability rather than efficacy, suggesting that targeted drugs designed to block 11-oxygenated androgens could eventually offer specific therapeutic options. The study received funding from the Wellcome Trust and the Medical Research Council, and the findings underscore the need for expanded research in an historically underfunded medical field.
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