Outcome of obstetric anal sphincter injuries in terms of persisting endoanal ultrasonographic defects and defecatory symptoms

OBJECTIVE: To determine the prevalence of persisting endoanal ultrasonographic defects among women with obstetric anal sphincter injuries (OASIS), and the incidence of defecatory symptoms. METHODS: In a prospective study in Enschede, Netherlands, women with OASIS were enrolled between 2007 and 2012. Three months after surgical repair, all women had an endoanal ultrasound, and data were collected on gas and fecal incontinence, soiling, and fecal urgency. RESULTS: Overall, 99 women were included. At follow-up, 35 (35.4%) women had a persisting defect of the external anal sphincter on ultrasound, and 5 women (5.1%) also had a persisting defect of the internal anal sphincter. Overall, 35 (35.4%) women had one or more defecatory complaints-predominantly involuntary loss of gas and fecal urgency. Overall, 22 of 35 (63.0%) women with and 13 of 64 (20.3%) women without a persisting defect on ultrasound had defecatory complaints. The number of defecatory symptoms showed a positive correlation with severity of injury. Women with a persisting defect had a threefold higher risk of defecatory complaints as compared with women who had a successful repair (odds ratio, 6.6; 95% confidence interval, 2.6-16.6). CONCLUSION: The results emphasize the importance of adequate repair of OASIS and demonstrate that repair can be difficult or underestimated.