The long-term prevalence of anal incontinence in women with and without obstetric anal sphincter injuries

Abstract

Introduction:Anal incontinence (AI) is a distressing and common condition for women. Women who sustain obstetric anal sphincter injuries (OASI) have been reported to have a higher prevalence of long-term AI than those who do not. However, the data is wide ranging, inconsistent and seldom comparative, with rates quoted varying between 13.1% and 74%. Methods:139 women who sustained OASI at their first delivery and 44 women who did not (controls) were contacted at 6 weeks and then a mean of 8 years following their first delivery. They were asked to complete a questionnaire including the St Mark’s Incontinence Score (SMIS) to assess the prevalence and severity of anal incontinence. Results:There was a high prevalence of anal incontinence (SMIS ≥1) in both women with OASI (62%) and controls (59%) (NS). The prevalence of severe AI (SMIS ≥ 6) was 27% in the OASI group and 18% in controls (NS). Higher grade tears and operative delivery were associated with higher rates of severe AI. In women with OASI, the mode of subsequent delivery did not impact the prevalence of AI. Conclusion:Women with OASI have a similar prevalence of long-term AI compared with women who do not sustain OASI. Some degree of AI is common 8 years post-partum, with our study demonstrating a high prevalence of 59% in controls. Brief summary:Women with and without OASI were contacted 5–15 years post-partum, and there was no difference in the rates of anal incontinence between the two groups.