Objective To estimate the risk for stress urinary incontinence and pelvic organ prolapse surgery related to vaginal birth or cesarean delivery. Study Design A cohort study of all women having their first and all subsequent deliveries by cesarean (n = 33,167), and an age-matched sample of women only having vaginal deliveries (n = 63,229) between 1973 and 1983. Hazard ratios were calculated using Cox regression models with 95% confidence intervals. Results Women only having vaginal deliveries had increased overall risks of incontinence (hazard ratio, 2.9; 95% confidence interval, 2.4–3.6) and prolapse surgery (hazard ratio, 9.2; 95% confidence interval, 7.0–12.1) compared with women only having cesarean deliveries. Conclusion Having only vaginal childbirths was associated with a significantly increased risk of stress urinary incontinence and pelvic organ prolapse surgery later in life compared with only having cesarean deliveries.