OBJECTIVE: The object of this study was to determine the prevalence of anal incontinence among women with previous multiple pregnancy and childbirth and assess risk factors. STUDY DESIGN: A 77-item questionnaire was administered to 769 mothers of multiples. Statistical analyses included X-2, Student t test, and logistic regression. RESULTS: Seven hundred thirty-three (95.3%) women completed the survey, 94% of them white, with a median age of 37 years. Fecal incontinence affected 10% (6.3% arose during pregnancy, 40.6% after delivery, 53.1% unrelated to childbirth). Although delivery by cesarean section only was associated with lower prevalence in univariate analysis (5.8% vs 11%, P =.02), age was the only significant covariate in multivariate regression (P =.0001). Flatal incontinence affected 25.2% (21.2% during pregnancy, 30.3% after delivery, 48.5% unrelated), increasing with age (P =.0001). Soiling affected 10%, increasing with age (P =.0001). CONCLUSION: Mothers of multiples reported substantial rates of fecal (10%) and flatal (25.2%) incontinence. Advancing age was the major risk factor. Delivery by cesarean section only was not significantly protective, although elective (before labor) cesarean deliveries were not separately assessed. (Am J Obstet Gynecol 2003;189:1627-31.)