Endometriosis Guidelines Differ on Biomarkers and Repeat Surgery

Most of the 47 endometriosis guidelines reviewed worldwide came from high-income settings, and they disagreed on biomarkers, repeat surgery, and fertility referral, according to a scoping review published October 14, 2026, in Communications Medicine.¹

Endometriosis affects about 10% of people of female sex of reproductive age, or roughly 190 million worldwide.² Diagnostic delays of 12 years or more have been reported, although some high-income settings have reduced that to about 6 years, according to the authors.¹ They noted that no globally applicable care guidance exists.

Guidelines Concentrate in High-Income Regions

The research team searched PubMed, Embase, and Scopus through October 2025 and grey literature through March 2026. They included 47 guidelines, 28 in English and 19 in other languages.

Thirty-eight were national guidelines, and 9 were international or regional. Europe produced about a third of all 47, while Africa accounted for 2% and the Eastern Mediterranean for 4%. Most guidelines (39) were original, and 8 were adaptations, most often of guidance from the European Society of Human Reproduction and Embryology, the National Institute for Health and Care Excellence, or the American College of Obstetricians and Gynecologists.

All guidelines targeted people of reproductive age, but 77% included adolescents, leaving roughly a quarter that did not, and 19% explicitly acknowledged gender-diverse individuals. Only 30% (14 guidelines) documented patient and public involvement in their development.

All guidelines were directed at gynecologists or fertility specialists, and 85% recommended a multidisciplinary team approach. Fewer than half (49%) explicitly included primary care clinicians.

Evidence Grading Varies Widely

Among the 39 original guidelines, 82% combined an evidence review with expert consensus, 8% relied on a systematic or evidence-based review alone, and 10% used expert consensus without a reported evidence review. The Grading of Recommendations Assessment, Development, and Evaluation framework was applied in 26%, while 44% used national or organizational grading systems and 31% issued ungraded recommendations.

More than 77% of guidelines addressed core diagnostic steps, including clinical assessment, pelvic examination, starting treatment before a confirmed diagnosis (empirical therapy), avoiding routine first-line laparoscopy, and specialist referral. Transvaginal ultrasound was recommended as first-line imaging, with magnetic resonance imaging reserved for suspected deep disease, in 94%.

For medical management, most guidelines recommended nonsteroidal anti-inflammatory drugs and hormonal therapy first, mainly combined oral contraceptives and progestins. Gonadotropin-releasing hormone analogues with add-back hormone therapy to offset adverse effects were recommended as second-line treatment in 79%.

Recommendations diverged on histological confirmation, the diagnostic value of biomarkers such as cancer antigen 125, repeat surgery, and excision vs ablation. Only 45% recommended aromatase inhibitors for refractory disease. Guidance on early fertility referral and avoiding routine surgery before assisted reproductive technology also varied. Among nonpharmacologic options, patient education (40%) and psychological support (30%) were recommended most often.

Authors Call for a Global Guideline

The authors concluded that a single global clinical guideline, adaptable to local settings, could promote methodological consistency and more equitable recommendations. They also called for guideline development in underrepresented regions, particularly Africa and the Eastern Mediterranean, and for broader inclusion of primary care and adolescent health providers.

The authors did not formally appraise guideline quality, so findings reflect the presence and content of recommendations rather than their rigor. The authors translated the 19 non-English guidelines with Google Translate and, where possible, had multilingual collaborators check them. The review also did not assess implementation or patient outcomes, and the authors noted that guideline availability is not a proxy for quality of care.

The study was supported by the Medical Research Future Fund. Several authors disclosed industry relationships, including consulting and speaker fees, and leadership roles with the World Endometriosis Society.

References

1. Gete DG, Evans D, Abbott J, et al. Global inequities and fragmentation in guidelines for endometriosis: a scoping review. Commun Med (Lond). 2026;6:495. doi:10.1038/s43856-026-01907-w
2. World Health Organization. Endometriosis. October 15, 2025. Accessed October 16, 2026. https://www.who.int/news-room/fact-sheets/detail/endometriosis