Antepartum pudendal neuropathy and the effect of vaginal delivery in women with type 1 diabetes mellitus in pregnancy

Abstract

Vaginal delivery is associated with a significant risk of pelvic floor neuropathy and anal sphincter dysfunction. Becauseinsulin-dependent diabetes mellitus (IDDM) predisposes to neuropathy, our aim was to determine the incidence of pudendalnerve dysfunction in a cohort of pregnant insulin-dependent diabetic patients and to examine the effect of vaginal delivery onpudendal nerve and anal sphincter function. Materials and Methods: The pudendal nerve was evaluated usingelectromyography of the anal sphincter (EMG) and clitoral anal reflex (CAR) assessment, during the third trimester in 16pregnant insulin-dependent diabetic women. Upper limb neurological assessment included median motor, ulnar f-wave,median and ulnar sensory nerve and median transpalmar nerve conduction studies, while the lower limbs were assessed usingtibial motor and f-wave studies. Anal manometry and endoanal ultrasound studies were also performed. Thirteen womenunderwent full reassessment at three months postpartum. Results: An increased sensory threshold (>9mA) on CAR wasdemonstrable antenatally in 5 women on the right and 8 on the left. Seven women showed prolonged distal latency (>42ms)on the right and in 8 on the left. Five women showed prolongation of median transpalmar nerve conduction studies (>2.2ms),which was associated with diabetes of greater than 12 years duration (p=0.029). The median squeeze pressure was 129mmHgand median resting pressure was 62mmHg. There were no significant changes in nerve conduction or anal manometricpressures postnatally. Discussion: Pregnant women with type 1 IDDM exhibit subtle changes of axonal neuropathy anddemyelination, but we found no increased susceptibility to pudendal nerve injury during vaginal childbirth. (Int J DiabetesMetab 14: 82-86, 2006 )