Effect of Vaginal Delivery on Perineal Descent and Pudendal Nerve Terminal Motor Latency

ABSTRACT

PURPOSE: Significant associations between perineal descent (PD) and pudendal nerve terminal motor latency (PNTML) have previously been described in patients with fecal incontinence. This had led to the hypothesis that pelvic floor muscle and nerve injury initiated by childbirth might progress and cause fecal incontinence. Purpose: This study was undertaken to evaluate the association between vaginal delivery and PD, PNTML. Also, we evaluated the correlation between PD and PNTML. Methods: Sixty one women who visited the Dept. of Surgery from Aug. 1998 to May. 1999 were randomly selected. Women were excluded, who had chronic constipation,operation within 6 months before the investigation, anal trauma, diabetes mellitus, and neurologic disease. They had a mean year of 43 12.5 years (range 23~70), a mean vaginal delivery 1.9 1.5 (range 0~6). PD at rest and during push, and PNTML were measured. Results: PD during push (p=0.006) and the change of PD between at rest and during push (p=0.003) were significantly increased with increasing number of vaginal deliveries. Rt PNTML (p=0.08) and Lt PNTML (p=0.03) were significantly increased with increasing number of vaginal deliveries. There was correlation between Lt PNTML and change of PD (r=0.59, p=0.0). Conclusions: PD and Lt PNTML was increased with repeated vaginal deliveries. Our findings support the hypothesis that damage induced by vaginal delivery to pudendal nerve and pelvic floor will progress.