Objective: To determine the prevalence of and factors associated with fecal incontinence in women with urinary incontinence or pelvic organ prolapse. Methods: Study subjects were recruited prospectively, and all participants received questionnaires regarding bowel function and underwent a standardized history and physical examination. Fecal incontinence was defined as the involuntary loss of feces sufficient to be considered a problem by the patient. Results: Forty-two subjects had fecal incontinence, an overall prevalence of 17%. One hundred seventy women had urinary incontinence, pelvic organ prolapse, or both, and 36 of these (21%) had fecal incontinence. One hundred (40%) women had urinary incontinence, of whom 31 also had fecal incontinence. Seventy women had isolated pelvic organ prolapse and five (7%) were incontinent of feces. Univariate analysis revealed that any degree of pelvic organ prolapse, increasing degrees of prolapse within each vaginal segment, urinary incontinence, advanced age, postmenopausal status, increased vaginal parity, prior hysterectomy, history of irritable bowel syndrome, and abnormal sphincter tone were associated significantly with fecal incontinence. Multiple logistic regression analysis indicated that only urinary incontinence (odds ratio [OR] 4.6, P < .001, 95% confidence interval [CI] 1.9, 11.2), abnormal anal sphincter tone (OR 2.3, P = .04, 95% CI 1.1, 5.1), and irritable bowel syndrome (OR 8.3, P = .002, 95% CI 2.1, 32.8) were associated with fecal incontinence. Conclusions: There is a high rate of fecal incontinence in women with urinary incontinence and pelvic organ prolapse. Clinicians providing health care to a similar group of women should inquire routinely and specifically about fecal incontinence.