Obstetric rectal buttonhole tear and a successful three-layer repair: A case report.

An obstetric rectal buttonhole tear (ORBT) is a rare obstetric complication with only 21 cases reported in the literature. The choice of two- or three-layer repair of ORBT is controversial. In this case, the author describes (with high-quality images) an ORBT repaired in three layers in order to provide clinical lessons to healthcare professionals involved in obstetrical care. The patient was a 26-year-old pregnant woman with a previous vertex delivery and 4 previous first-trimester miscarriages. In the index pregnancy, she had a spontaneous vertex vaginal birth of a 3095 g male baby at 39 weeks of gestation. During childbirth, she sustained an ORBT and a third-degree perineal tear involving <50% of the external anal sphincter. The ORBT was repaired in three layers using continuous 2-0 Vicryl to the rectal mucosa, and interrupted polydioxanone (PDS) 3-0 to the adjoining vagino-rectal fascia. Subsequently, the external anal sphincter was repaired end-to-end with interrupted PDS 3-0. Thereafter, the vagina was repaired with continuous Vicryl 2-0. The wound healed with no complications over the 12 weeks of postnatal clinic visits. A three-layer repair is arguably preferable given that closure of the fascia between the rectal and vaginal mucosae (vagino-rectal fascia) may improve the tensile strength at the injury site. However, a two-layer repair may be undertaken in rare cases where the vagino-rectal fascia is not identifiable.