1. To evaluate whether a standardized tension-free vaginal tape-obturator(TVT-O) procedure, when added to a planned improved reconstruction pelvic surgery, improves the rate of urinary stress continence in subjects with occult stress incontinence.
2. Observe the immediate and short-term complications, overall urinary tract function, and other aspects of pelvic health between subjects with and without a TVT-O procedure.

The primary aim of this randomized study is evaluate whether a standardized TVT-O procedure, when added to a planned improved reconstruction pelvic surgery for the treatment of pelvic organ prolapse, improves the rate of urinary stress continence in subjects with occult stress incontinence. Secondary aims include comparison of immediate and short-term complications, overall urinary tract function, and other aspects of pelvic health between subjects with and without a TVT-O procedure. The value of preoperative urodynamic testing with prolapse reduction and 1 hour pad test will also be compared between subjects with and without a concomitant TVT-O procedure.

Inclusion Criteria:

• In the absence of medical contraindications for improved pelvic floor reconstruction surgery and the TVT-O surgery
• Bulge of paries anterior vaginas stage III-IV
• Uterine prolapse stage II-II
• Without symptoms of stress urinary incontinence
• Screening tests of occult stress urinary incontinence(OSUI) should be positive
• ≥55 years old.

Exclusion Criteria:

• Pregnancy
• Illegible to follow up after surgery
• Previous surgery for stress urinary incontinence
• Unfinished data collection before surgery