This animation displays the sagittal and inferior views of a perineal laceration with layered repair. Structures in these views include the internal anal sphincter, external anal sphincter, rectum, anus, peritoneum, and the vagina. Descent and enlargement of the fetal head during delivery leads to a site of midline episiotomy and a fourth degree perineal tear. The doctor repairs this laceration through the use of sutures and performs a digital exam to ensure the repair is intact. Complete failure of the laceration repair occurs during the passage of a large, firm bowel movement.
