Risk of urinary incontinence after childbirth: a 10-year prospective cohort study.

OBJECTIVE

To estimate prospectively the effect of first delivery on subjective bladder function and to assess the influence of subsequent deliveries and obstetric events

METHODS

We performed a prospective, observational cohort study. During a 10-week period in 1995, 304 of 309 eligible primiparous women (98%) entered the study at the postpartum maternity ward and completed a bladder function questionnaire. The 10-year observational period was completed by 246 of 304 subjects (81%).

RESULTS

Prevalence of moderate-severe stress urinary incontinence increased from 5 of 304 subjects (2%) at baseline to 27 of 229 (12%) at 10 years follow-up (P < .001). Prevalence of moderate-severe urinary urgency increased from 0 subjects (0%) at baseline to 31 of 229 (13%) at the 10-year follow-up (P < .001). The relative risk (RR) (adjusted for maternal age and parity) of moderate to severe urinary incontinence increased significantly 10 years after first delivery (RR 5.8, 95% confidence interval [CI] 1.2-33.7). At multivariable analysis adjusted for age and parity, stress urinary incontinence symptoms at 9 months and 5 years follow-up were independently associated with the presence of symptoms at 10 years after index delivery (RR 13.3, 95% CI 3.9-33.1 and RR 14.1, 95% CI 2.5-18.8, respectively). Number of vaginal deliveries or other obstetric covariates did not affect the risk of stress urinary incontinence or urinary urgency.

CONCLUSION

Vaginal delivery is independently associated with a significant long-term increase in stress urinary incontinence symptoms, as well as urinary urgency, regardless of maternal age or number of deliveries.

LEVEL OF EVIDENCE

II-2.