Effect of mode of delivery on the incidence of urinary incontinence in primiparous women.

OBJECTIVE

To estimate the effect of mode of delivery on the incidence of urinary incontinence in primiparous women.

METHODS

A population-based survey was mailed to all Oregon women who delivered a liveborn neonate in a 1-year period. Data were collected on urinary incontinence, childbirth experience, and other risk factors for incontinence at 3-6 months postpartum. Univariable analyses were conducted using t tests and Wilcoxon rank-sum tests for continuous variables and chi tests for categorical variables. Logistic regression analyses were used to estimate odds ratios and 95% confidence intervals for demographic and clinical risk factors.

RESULTS

A total of 15,787 women completed the survey, for a response rate of 39%. Of these women, 5,599 were primiparous, completed the survey in the desired timeframe, submitted information on their urinary continence, and did not have incontinence before pregnancy. A total of 955 (17.1%) reported leakage of urine. Women who had vaginal deliveries were more likely to have urinary incontinence than women who had cesarean deliveries (odds ratio 4.96 [95% confidence interval 3.82-6.44], P<.001). This risk increased with assisted delivery and perineal laceration. No statistical difference in the incidence of urinary incontinence was found among women who had elective cesarean deliveries (6.1%), women who had cesarean deliveries after laboring (5.7%), and women who had cesarean deliveries after laboring and pushing (6.4%).

CONCLUSION

Urinary incontinence is common in the immediate postpartum period after a woman's first pregnancy. Although vaginal delivery increases the risk of urinary incontinence, labor and pushing alone without vaginal delivery do not appear to increase this risk significantly.

LEVEL OF EVIDENCE: II.