Endometriosis among Transgender and Gender Diverse Patients Imaging Study (ETRIS).

Objective: to assess the prevalence of surgically confirmed endometriosis among assigned-female-at-birth (AFAB) transgender and gender diverse (TGD) individuals undergoing laparoscopic pelvic surgery.

Design: retrospective multicenter cohort study from 2021 to 2024.

Setting: three academic medical centers in the Netherlands and the United Kingdom.

Participants: Eligible participants were AFAB TGD individuals aged ≥18 years who underwent pelvic laparoscopic surgery for any indication, including gender incongruence/dysphoria.

Interventions: Data on demographics, medical history, and diagnostic imaging were analyzed using descriptive statistics. Surgical confirmation of endometriosis was the primary outcome.

Results: Among 325 participants, endometriosis prevalence was 3.1% (n=10). The mean age of participants was 27.2 years and the mean body mass index (BMI) 24.9. Testosterone was predominantly used before surgery (95.4%), and among these users, 38.5% had been on testosterone for five or more years at the time of surgery. Overall, 6% of the sample reported dysmenorrhea, and among those with endometriosis, 30% experienced dysmenorrhea.

Conclusion: Endometriosis was present in 3.1% of the sample. This finding differs from previous literature as it reports a lower prevalence compared to cisgender women and to other studies on TGD people. This is potentially due to prolonged use of testosterone and early initiation of gender-affirming care (GAC).