Risk of ruptured uterus is approximately 1%.
Approximately 1.3% of women who undergo a trial of labor have major complications.
Of patients with complications 12.5-20% require hysterectomy, 12.5-25% have fetal death, 16.6-25% have permanent fetal injury, and <1% have maternal death.
If it fails and repeated cesarean section is performed maternal morbidity, including infection and operative injuries increases substantially.
Failure associated with prelabor factors of maternal age >30 years, fetal weight >4000g, induction of labor, absence of previous vaginal delivery and previous cesarean delivery for dystocia.
Reasonable choice in women whose previous cesarean was for dystocia in the second stage of labor with a greater than 75% chance of achieving vaginal delivery.
Is inappropriate if an emergency cesarean delivery cannot be performed because of unavailability of surgical and anesthesia support.