Urinary incontinence after vaginal delivery or cesarean section.

Background: It is uncertain whether women who deliver by cesarean section have an increased risk of urinary incontinence as compared with nulliparous women and whether women who deliver vaginally have an even higher risk.

Methods: We studied 15,307 women enrolled in the Epidemiology of Incontinence in the County of Nord-Trøndelag (EPINCONT) study, which involved a community-based cohort. The data base for this study was linked to data from the Medical Birth Registry of Norway. We included women who answered questions related to urinary incontinence, were younger than 65 years of age, and had had no deliveries, cesarean sections only, or vaginal deliveries only.

Results: The prevalence of any incontinence was 10.1 percent in the nulliparous group; age-standardized prevalences were 15.9 percent in the cesarean-section group and 21.0 percent in the vaginal-delivery group. Corresponding figures for moderate or severe incontinence were 3.7 percent, 6.2 percent, and 8.7 percent, respectively; figures for stress incontinence were 4.7 percent, 6.9 percent, and 12.2 percent, respectively; figures for urge incontinence were 1.6 percent, 2.2 percent, and 1.8 percent, respectively; and figures for mixed-type incontinence were 3.1 percent, 5.3 percent, and 6.1 percent, respectively. As compared with nulliparous women, women who had cesarean sections had an adjusted odds ratio for any incontinence of 1.5 (95 percent confidence interval, 1.2 to 1.9) and an adjusted odds ratio for moderate or severe incontinence of 1.4 (95 percent confidence interval, 1.0 to 2.1). Only stress and mixed-type incontinence were significantly associated with cesarean sections. The adjusted odds ratio for any incontinence associated with vaginal deliveries as compared with cesarean sections was 1.7 (95 percent confidence interval, 1.3 to 2.1), and the adjusted odds ratio for moderate or severe incontinence was 2.2 (95 percent confidence interval, 1.5 to 3.1). Only stress incontinence (adjusted odds ratio, 2.4; 95 percent confidence interval, 1.7 to 3.2) was associated with the mode of delivery.

Conclusions: The risk of urinary incontinence is higher among women who have had cesarean sections than among nulliparous women and is even higher among women who have had vaginal deliveries. However, these findings should not be used to justify an increase in the use of cesarean sections.