BACKGROUND Obesity, well known as a risk factor for several diseases, can also lead to pelvic floor dysfunction (PFD). However, scant data are available regarding PFD in obese individuals. Our study was designed to assess the prevalence, severity, and the quality of life (QOL) effect of PFD in obese women before and after bariatric surgery at a university hospital in Italy. METHODS A total of 100 obese (body mass index [BMI] ≥30 kg/m(2)) women completed 6 validated specific and QOL questionnaires about PFD. The patients were evaluated by physical examination, endoanal ultrasonography, rectal balloon distension test, and dynamic magnetic resonance imaging. Of the 100 patients, 87 were reassessed 12 months after bariatric surgery. RESULTS The prevalence of PFD was 81%, and 49% of patients reported that their symptoms adversely affected their QOL. Urinary incontinence (UI) was the most common disorder (61%) and was associated with the BMI (P = .04). Fecal incontinence and pelvic organ prolapse symptoms were reported by 24 and 56 patients, respectively. Urogenital prolapse and rectocele was documented in 15% and 74% of patients, respectively. After a mean BMI reduction of 10 kg/m(2), the prevalence of PFD decreased to 48% (P = .02), with a significant improvement in QOL. The prevalence of UI decreased to 9.2% (P = .0001) and was associated with the decrease in postoperative BMI (P = .04). The rate of resolution of the symptoms was 84%, 85%, and 74% for UI, fecal incontinence, and pelvic organ prolapse, respectively. CONCLUSION In the present sample of obese women, PFD was common and adversely affected their QOL. A clear association was found between the BMI and UI. Weight loss resulted in improved UI, fecal incontinence, and symptoms of pelvic organ prolapse.