Anal incontinence in women with third or fourth degree perineal tears and subsequent vaginal deliveries

We contacted 208 women 13 years after they suffered an obstetrical anal sphincter tear in order to estimate the effect of subsequent vaginal deliveries on anal continence. Among the 177 eligible responders, 129 sustained a partial or complete 3rd degree and 48 a 4th degree tear; 114 women had subsequent vaginal deliveries. Anal incontinence was more common in women with 4th (25.0%) than with 3rd degree tears (11.5%, p = 0.049). Subsequent vaginal deliveries were associated with a higher prevalence of severe incontinence in women with 4th degree tears (p = 0.023). No aggravation or increase in prevalence of incontinence was observed in women with 3rd degree tears. These results suggest that in a subsequent pregnancy, careful evaluation is necessary and an abdominal delivery may be advisable for women with previous major sphincter trauma.