The study population consists of women with pelvic organ prolapse and occult stress urinary incontinence. They are randomised within two groups : one group with pelvic organ prolapse surgery alone and one group with implantation of TOT together with prolapse surgery for prevention of stress urinary incontinence.TOT implantation is performed as described previously, while the pelvic organ prolapse surgery could either be of abdominal (open or laparoscopic) or vaginal approach. Eighty eight (88) patients will be enrolled at 3 sites centers.