Inclusion Criteria:  Patients with "III-IV degree uterine/apex/anterior vaginal wall prolapse and I-II degree of posterior vaginal wall prolapse" who agree to be treated by transvaginal pelvic mesh implantation. All surgeries were performed by surgeons with extensive experience in transvaginal mesh implantation (>20 vaginal mesh implantation per year) using macroporous, monofilament, polypropylene mesh.  Exclusion Criteria:  1. Have had sex in the past 5 days or had vaginal irrigation; 2. Use oral or vaginal antibiotics, antifungal, immunosuppressant, hormone drugs or probiotics for the last 30 days. 3. Combined with immunosuppressive diseases, diseases with contraindication of vaginal estrogen such as breast cancer, endometrial cancer. 4. If the patient has a uterus before surgery and does not undergo total transvaginal hysterectomy during surgery, 5. Intraoperative bladder injury or intraoperative hemorrhage >500ml or postoperative hematoma.