Anal incontinence after vaginal delivery: a prospective study in primiparous women

Objective To investigate the incidence and degree of anal incontinence afte r vaginal delivery among primiparous women and to define associated risk fa ctors. Design Prospective observational study. Setting Karolinska Institutet, Danderyd Hospital, Sweden, a university hosp ital. Participants Three hundred and forty-nine primiparous women. Methods Questionnaires distributed within the first days after delivery and re-distributed five and nine months postpartum. Analysis of delivery recor ds. Results Eighty percent of the women answered all questionnaires. At five mo nths postpartum, 2% of the women had symptoms of faecal incontinence and 25 % had symptoms of involuntary flatus. At nine months postpartum, 1% of the women had symptoms of faecal incontinence and 26% had symptoms of involunta ry flatus. The majority of the women had infrequent symptoms and a decrease in severity was noted at nine months. Symptoms of incontinence were more c ommon in women who sustained a sphincter tear at delivery. Risk factors for incontinence at five months included maternal age, duration of the second stage of labour, instrumental vaginal delivery, and clinically diagnosed sp hincter tear at delivery. Development of incontinence at nine months was as sociated with maternal age and clinically diagnosed sphincter lear at deliv ery. Conclusions The present study demonstrates that infrequent involuntary flat us is a common symptom after vaginal delivery in primiparous women. These s ymptoms of involuntary flatus frequently improved and only a few women suff ered from frank faecal incontinence. Factors associated with an increased r isk of anal incontinence and sphincter tears should be considered during de livery.