Trends in pelvic pain symptoms over 2 years of follow-up among adolescents and young adults with and without endometriosis

We described trends in pelvic pain characteristics over 2 years of follow-up among adolescents and adults with and without endometriosis participating in the longitudinal observational cohort of the Women's Health Study: From Adolescence to Adulthood, using data reported at baseline and at years 1 and 2 of follow-up. Participants completed a questionnaire at baseline (between November 2012 and May 2019) and annually thereafter that included validated measures of severity, frequency, and life interference of dysmenorrhea, acyclic pelvic pain, and dyspareunia. Our study population included 620 participants with surgically confirmed endometriosis (rASRM stage I/II = 95%) and 671 community-based and hospital-based controls, with median age = 19 and 24 years, respectively. The proportion reporting hormone use varied across the 3 years ranging from 88% to 92% for cases and 56% to 58% for controls. At baseline, endometriosis cases were more likely to report severe, frequent, and life-interfering dysmenorrhea, acyclic pelvic pain, and dyspareunia compared with controls. Among cases, frequency and severity of dysmenorrhea and dyspareunia were relatively static across 2 years. However, acyclic pelvic pain improved. Severe acyclic pain decreased from 69% at baseline to 46% at year 2. Daily pain decreased from 28% to 14%, and life interference from 68% to 38%. Trends among controls remained fairly stable across 2 years. Among endometriosis cases who completed the questionnaire at all 3 time points, 18% reported persistent, severe acyclic pelvic pain at all 3 time points. Over time, different trends were observed by pelvic pain type among endometriosis cases and controls, supporting the importance of assessing multidimensional features of pelvic pain.