Uterine rupture during a trial of labor after previous cesarean delivery.

Uterine rupture, which involves complete separation of the uterine wall, occurs in about 1% of those attempting vaginal birth after cesarean. Because uterine rupture is one of the most significant complications of a trial of labor (TOL) after previous cesarean, identifying those at increased risk of uterine rupture is paramount to the safety of a TOL after previous cesarean birth. It seems that both antepartum demographic characteristics and intrapartum factors modify the risk of uterine rupture. The ability to reliably predict an individual's a priori risk for intrapartum uterine rupture remains a major area of investigation.