Endometriosis risk factors

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Joseph Nasr, M.D.[2] Aravind Kuchkuntla, M.B.B.S[3]

Risk factors predisposing women to the development of endometriosis include early age at menarche, nulliparity, positive family history, and the presence of congenital cervical stenosis or obstructive lesions in the uterovaginal tract. Additional epidemiologic risk factors include short menstrual cycle length, lower body mass index, and obstructive Müllerian anomalies.^[1][2]

Twin studies estimate the heritability of endometriosis to be approximately 50%.^[3]

The risk factors predisposing women to develop endometriosis include the following:^[4][5]

• Presence of cervical stenosis and other congenital outflow obstructions (leads to the retrograde efflux of the menstrual fluid into the fallopian tubes and peritoneal cavity); among individuals with obstructive Müllerian anomalies, the prevalence of endometriosis is 47% (95% CI, 36%–58%).^[1]
• Caffeine or alcohol use
• First-degree family relative with endometriosis (relative risk among sisters 5.2; 95% CI, 3.4–7.2).^[6][7]
• Nulliparity (associated with increased risk; pregnancy may be protective due to prolonged anovulation).^[8]
• Menarche before 12 years of age (associated with increased risk).^[2]
• Short menstrual cycle length (<28 days), associated with increased risk.^[9]
• Lower body mass index (associated with increased risk).^[10]
• Tall stature
• Genetic susceptibility with estimated heritability of approximately 50%.^[11]