Background: Pelvic organ prolapse (POP) affects a considerable proportion of women. Limited information exists regarding the incidence of POP as women transition through menopause. Using data from the Study of Women's Health Across the Nation (SWAN), this diverse community-based longitudinal cohort study assessed the incidence of symptomatic POP and risk by race/ethnicity. Methods: Self-reported POP was ascertained by questionnaire at 11 approximately annual SWAN visits over a median of 13.3 years of follow-up. We estimated probabilities for reporting POP using interval-censored Kaplan-Meier survival plots. We estimated hazard ratios (HR) and 95% confidence intervals (CI) using interval-censored Cox proportional hazards models. Results: The estimated cumulative probability of POP increased linearly from 2.1% at age 45 to 10.1% by age 65 (4.0% per decade). At age 65, the probability was 4.2%, 4.8%, 8.9%, 9.7%, and 33.9% for Japanese, Chinese, Black, White, and Hispanic women, respectively. Compared with White women, the unadjusted HR for POP was 3.09 (95% CI = 2.18-4.39), 0.96 (0.71-1.31), 0.43 (0.22-0.85), and 0.48 (0.26-0.88) for Hispanic, Black, Chinese, and Japanese women, respectively. After adjustment for financial strain and vaginal birth, the low hazards among Chinese and Japanese women and the high hazard for Hispanic women remained significant. Conclusion: Incidence of symptomatic POP increased as women aged through midlife. Risks varied by race and ethnicity and were not accounted for by population differences in socioeconomic life contexts or the probability of having had a vaginal birth. Although not associated with menopause, health providers should incorporate screening for and information about POP when treating menopausal symptoms and health needs of midlife women. Research on pathophysiological factors associated with increasing POP in midlife is warranted.
Keywords: cohort study; ethnicity; incidence; midlife; pelvic organ prolapse; race.