East and South East Asian Ethnicity and Moderate-to-Severe Endometriosis

To investigate ethnic differences for moderate-to-severe endometriosis.

Analysis of a prospective registry (Canadian Task Force classification II-2).

Tertiary referral center.

A total of 1594 women with pelvic pain and/or endometriosis.

None MEASUREMENTS AND MAIN RESULTS: On logistic regression, adjusting for potential confounders, East/South East Asians were 8.3 times more likely than whites to have a previous diagnosis of stage III/IV endometriosis before referral (adjusted odds ratio [aOR], 8.33; 95% confidence interval [CI], 3.74-18.57), 2.7 times more likely to have a palpable nodule (aOR, 2.66; 95% CI, 1.57-4.52), 4.1 times more likely to have an endometrioma on ultrasound (aOR, 4.10; 95% CI, 2.68-6.26), and 10.9 times more likely to have stage III/IV endometriosis at the time of surgery at our center (aOR, 10.87; 95% CI, 4.34-27.21).

Moderate-to-severe endometriosis was more common in women with East or South East Asian ethnicity in our tertiary referral center.  This could be explained by East/South East Asians with minimal to mild disease being less likely to seek care or genetic/environmental differences that increase the risk of more severe disease among East/South East Asians. (ClinicalTrials.gov, NCT02911090.).