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

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.