OBJECTIVE To study the long-term effects of vaginal dissection on the innervation of the striated urethral sphincter. METHODS Perineal nerve terminal motor latency was measured before and 8 weeks and 1 year after anterior colporrhaphy, colpoperineoplasty, and vaginal hysterectomy in 33 women, 19 of whom also underwent endoscopic suspension of the bladder neck. RESULTS In the entire series, the mean perineal nerve terminal motor latency was prolonged before surgery over that in normal continent women and further prolonged 8 weeks and 1 year postoperatively. In the subjects who underwent vaginal hysterectomy and anterior colporrhaphy, perineal motor latencies were not significantly prolonged at the 8-week postoperative follow-up and had almost returned to preoperative values 1 year later. However, in those who underwent additional endoscopic bladder neck suspension, perineal motor latencies were prolonged at both postoperative follow-up examinations. Perineal motor latencies were unchanged 1 year postoperatively in continent patients (N = 19) but were prolonged in incontinent patients (N = 14). CONCLUSIONS Vaginal dissection, especially during endoscopic bladder neck suspension, can worsen preexisting perineal neuropathy in patients with pelvic relaxation and stress incontinence.