Obstetric rectal laceration in the absence of an anal sphincter injury.

Rectal laceration in the absence of concurrent anal sphincter injury at the time of parturition is not a frequently reported finding. This rarely encountered injury is also referred to as a buttonhole injury. It is a disruption of the vaginal and rectal tissue with resultant disruption of the anal epithelium in the setting of an intact external anal sphincter. A 30-year-old gravida 1 para 0 at 39 weeks presented for induction of labour due to chronic hypertension. During her labour course, she developed with superimposed preeclampsia with severe features and magnesium sulfate was initiated. She underwent a spontaneous vaginal delivery of an infant weighing 3840 g. Following delivery, stool was visualised in the vagina. A rectal examination revealed a rectovaginal defect separate from the second-degree perineal laceration, which extended proximally to the cervix. The anal sphincter was noted to be intact with good tone. Both defects were repaired, and she had an uncomplicated recovery.