Does cesarean section reduce postpartum urinary incontinence? A systematic review.

BACKGROUND The impact of delivery mode on the development of urinary incontinence has been much debated. The primary objective of this systematic review was to compare the prevalence of postpartum urinary incontinence after cesarean section compared with vaginal birth. METHODS The MEDLINE (1966-2005) and CINAHL (1982-2005) databases were searched for reports specifying postpartum prevalence or incidence of unspecified, stress, urge, and mixed urinary incontinence by mode of birth. Primary authors were contacted to request unpublished data about severity, parity, and timing of cesarean section. All data were entered into Review Manager software, and odds ratio (OR), absolute risk reduction, and number needed to prevent were calculated. RESULTS Cesarean section reduced the risk of postpartum stress urinary incontinence from 16 to 9.8 percent (OR = 0.56 [0.45, 0.68], number needed to prevent = 15 [12,22]) in 6 cross-sectional studies, and from 22 to 10 percent in 12 cohort studies (OR=0.48 [0.39, 0.58], number needed to prevent = 10 [8,13]). Differences persisted by parity and after exclusion of instrumental delivery, but risk of severe stress urinary incontinence and urge urinary incontinence did not differ by mode of birth. CONCLUSIONS Although short-term occurrence of any degree of postpartum stress urinary incontinence is reduced with cesarean section, severe symptoms are equivalent by mode of birth. Risk of postpartum stress urinary incontinence must be considered in the context of associated maternal and newborn morbidity and mortality.