Obstetric Anal Sphincter Injury

A 26-year-old woman complained of flatus and fecal incontinence of solid stool. One year earlier, she was delivered of a 3.86-kg (8.5-lb) infant; a severe perineal tear was repaired after the birth.

A very attenuated perineal body with poor resting and squeeze pressures was noted on digital rectal examination. The anovaginal septum was scarred and foreshortened. Results of a flexible sigmoidoscopic examination were normal.

An unrecognized or improperly repaired traumatic tear to the sphincter muscles can occur after a vaginal birth. A midline episiotomy is associated with an increased risk of sphincter damage.¹ Surgical repair after careful anorectal assessment and evaluation of the severity of anal incontinence is usually successful.

This patient underwent overlapping sphincteroplasty to repair the anal sphincter. The procedure restored complete anal continence.