OBJECTIVES: The objectives of this work were to determine the prevalence of irritable bowel syndrome (IBS) and IBS subtypes in women presenting for fecal incontinence (FI) treatment and to assess the impact of IBS on FI symptoms and quality of life (QOL). METHODS: In this multicenter prospective cohort study, women reported at least monthly solid, liquid, or mucus FI. Rome III clinical criteria defined IBS. Women also self-reported having an IBS diagnosis. Baseline questionnaires included the following: Modified Manchester Health Questionnaire, Fecal Incontinence Severity Index, Bristol Stool Scale, Pelvic Floor Distress Inventory, and the Pelvic Floor Impact Questionnaire. RESULTS: Of the 133 women enrolled, 119 completed Rome III IBS questionnaires, and 111 reported on whether they had a previous diagnosis of IBS. The prevalence of IBS was 31% (95% confidence interval [CI], 22.9%-40.2%) according to the Rome III IBS criteria. The most common subtypes were IBS-mixed (41%) and IBS-diarrhea (35%). Twenty-four (22%) of 111 patients had a previous diagnosis of IBS. Among women who met Rome III IBS criteria, 23 (66%) of 35 women had never had a diagnosis of IBS. Women with FI and IBS reported significantly worse QOL compared to women without IBS despite similar FI severity and stool consistency. CONCLUSIONS: Irritable bowel syndrome negatively affects QOL and affects one third of women with FI presenting for care in tertiary centers. Our findings suggest that assessment of IBS symptoms and diagnosis may be important for women presenting for FI treatment.