Bowel dysfunction: a pathogenic factor in uterovaginal prolapse and urinary stress incontinence

Abstract

Objective To investigate the aetiological importance of bowel dysfunction in patients with uterovaginal prolapse and urinary stress incontinence. Design Observational study using a questionnaire about obstetric history and bowel function, and anorectal physiological studies. Setting Physiology unit and gynaecological outpatients departments of two teaching hospitals. Subjects Twenty-three women with uterovaginal prolapse (mean age 57 years), 23 women with urinary stress incontinence (mean age 52 years) and 27 control women (mean age 52 years). Results There was no statistically significant difference between the three groups in their parity, age or birthweight of their children. However, straining at stool as a young adult prior to the development of urogynaecological symptoms was significantly more common in women with uterovaginal prolapse (61%vs 4%, P < 0.001) and women with urinary stress incontinence (30%vs 4%, P < 0.05), compared with controls. A bowel frequency of less than twice per week as a young adult was also more common in women with uterovaginal prolapse than in control women (48%vs 8%, P < 0.001). At the time of consultation, 95% of the women with uterovaginal prolapse were constipated, compared with only 11% of control women. Many of these women also needed to digitate to achieve rectal evacuation. Compared with controls, women with uterovaginal prolapse had a prolonged pudendal nerve terminal motor latency (1.9 ms vs 2.2 ms, respectively, P= 0.003). Women with stress incontinence of urine had a normal pudendal nerve latency (2.0 ms). Other tests of anorectal function were normal. Conclusions Constipation, in addition to obstetric history, appears to be an important factor in the pathogenesis of uterovaginal prolapse.