Rate of uterine rupture during a trial of labor in women with one or two prior cesarean deliveries

OBJECTIVE: We sought to determine whether there is a difference in the rate of symptomatic uterine rupture after a trial of labor in women who have ha d 1 versus 2 prior cesarean deliveries. STUDY DESIGN: The medical records of all women with a history of either 1 o r 2 prior cesarean deliveries who elected to undergo a trial of labor durin g a 12-year period (July 1984-June 1996) at the Brigham and Women's Hospita l were reviewed. Rates of uterine rupture were compared for these 2 groups. Potential confounding variables were controlled by using logistic regressi on analyses. RESULTS: Women with 1 prior cesarean delivery (n = 3757) had a rate of uter ine rupture of 0.8%, whereas women with 2 prior cesarean deliveries (n = 13 4) had a rate of uterine rupture of 3.7% (P = .001). in a logistic regressi on analysis that was controlled for maternal age, use of epidural analgesia , oxytocin induction, oxytocin augmentation, the use of prostaglandin E-2 g el, birth weight, gestational age, type of prior hysterotomy, year of trial of labor. and prior Vaginal delivery, the odds ratio for uterine rupture i n those patients with 2 prior cesarean deliveries was 4.8 (95% confidence i nterval, 1.8-13.2) CONCLUSIONS: Women with a history of 2 prior cesarean deliveries have an al most 5-fold greater risk of uterine rupture than those with only 1 prior ce sarean delivery.