Introduction and hypothesis: To evaluate an association between hysterectomy and urinary incontinence (UI) in postmenopausal women.
Methods: Women (aged 50-79) with uteri (N = 53,569) and without uteri (N = 38,524) who enrolled in the Women's Health Initiative (WHI) Observational Study between 1993 and 1996 were included in this secondary analysis. Baseline (BL) and 3-year demographic, health/physical forms and personal habit questionnaires were used. Statistical analyses included univariate and logistic regression methods.
Results: The baseline UI rate was 66.5 %, with 27.3 % of participants having stress urinary incontinence (SUI), 23 % having urge UI (UUI), and 12.4 % having mixed UI (MUI). 41.8 % of women had undergone hysterectomy, with 88.1 % having had the procedure before age 54. Controlling for health/physical variables, hysterectomy was associated with UI at BL (OR 1.25, 95 % CI 1.19, 1.32) and over the 3-year study period (OR 1.23, 95 % CI 1.11, 1.36). Excluding women with UI at BL, a higher incidence of UUI and SUI episodes was found in hysterectomy at year 3. Among women who had undergone hysterectomy, those with bilateral oophorectomy (BSO) did not have increased odds of developing UI at BL or over the 3-year study period. Hormone use was not associated with a change in UI incidence (estrogen + progesterone, p = 0.17; unopposed estrogen, p = 0.41).
Conclusions: Risk of UI is increased in postmenopausal women who had undergone hysterectomy compared with women with uteri.