161: Timing of delivery in women with prior uterine rupture: A decision analysis

Abstract

Limited data are available to guide the timing of delivery in women with a history of prior uterine rupture. The purpose of this study is to determine the optimal gestational age (GA) to perform a repeat cesarean in women with prior uterine rupture. A decision-analytic model was built using TreeAge software to compare the outcomes of repeat cesarean delivery when performed at 32-36 weeks’ gestation in a theoretic cohort of 100 women with prior uterine rupture. Strategies involving expectant management until a later GA accounted for the risks of spontaneous rupture, spontaneous delivery, uterine rupture following spontaneous labor, and IUFD during each successive week. Maternal outcomes included death and hysterectomy. GA-associated risks of neonatal complications included neonatal death and cerebral palsy. Probabilities were derived from the literature and total quality-adjusted life years (QALYs) were calculated. Univariate sensitivity analyses were used to vary model inputs to investigate the robustness of our baseline assumptions. We assumed a 0.6% baseline rate of spontaneous repeat uterine rupture. In our theoretical cohort of 100 women, compared to 36 weeks’ gestation, repeat cesarean at 34 weeks would prevent 3.86 uterine ruptures (Table 1). Additionally, the prevention of recurrent uterine rupture would lead to 0.0079 fewer maternal deaths, 0.61 fewer hysterectomies, and 1.22 fewer neonatal deaths. However, delivery at 36 weeks as opposed to 34 weeks would result in 0.47 fewer cases of cerebral palsy. Balancing these outcomes, repeat cesarean delivery at 34 weeks was optimal as it maximized maternal and neonatal QALYs. Univariate sensitivity analysis found that repeat cesarean at 34 weeks remained the optimal strategy until the probability of spontaneous repeat uterine rupture fell below 0.2% or rose above 0.9% (Figure 1). Weighing the risks of maternal morbidity and mortality against GA-associated neonatal complications, the optimal time for repeat cesarean delivery in women with prior uterine rupture is at 34 weeks.View Large Image Figure ViewerDownload Hi-res image Download (PPT)