OBJECTIVE To investigate whether the sonographically measured size of the mesh implant in women who had undergone vaginal polypropylene mesh repair 6 weeks previously correlates with the original size of the mesh and whether the mesh ensures complete support of the anterior or posterior compartment. METHODS Forty postmenopausal women with anterior or posterior vaginal wall prolapse and sonographically proven cystocele (n = 20) or rectocele (n = 20) were evaluated preoperatively and 6 weeks after vaginal mesh repair. Introital ultrasound was performed to identify the polypropylene mesh and measure its distal to proximal length and configuration as well as its thickness. The initial mesh length was compared with that measured by ultrasound 6 weeks postoperatively. Vaginal length was measured pre- and postoperatively. RESULTS The mean +/- SD age of the women was 68 +/- 7 years. The 20 women with cystocele underwent repair by means of anterior transobturator mesh implantation; the initial mesh length was 6.8 +/- 1.1 cm versus 2.9 +/- 0.6 cm postoperatively. The 20 women with rectocele underwent repair by posterior transischioanal mesh implantation; the initial mesh length was 9.9 +/- 0.8 cm versus 3.3 +/- 0.5 cm postoperatively. The mesh supported 43.4% of the length of the anterior vaginal wall and this value was 53.7% for the posterior wall (P = 0.016). CONCLUSIONS Sonography is recommended for postoperative evaluation of the anterior and posterior mesh positions after prolapse surgery. There is a considerable discrepancy between the implanted mesh size and the length measured 6 weeks later by postoperative ultrasound. Published by John Wiley & Sons, Ltd.