26: Elective induction of labor at 39 weeks versus expectant management in low-risk multiparous women

Abstract

The ARRIVE Trial demonstrated lower cesarean delivery rates, decreased hypertensive disorders of pregnancy and potentially improved perinatal outcomes in low-risk nulliparous women undergoing elective induction of labor (eIOL) at 39 weeks as compared to expectant management (EM). Our objective was to compare maternal and neonatal outcomes between eIOL and EM in low-risk multiparous women. A retrospective cohort study of low-risk multiparas (previous delivery ≥20 weeks with no prior cesarean) delivering non-anomalous singletons between 390-420 weeks from 2014-2017 at our institution. Women were considered eIOL if they delivered between 390 - 394 weeks following an IOL without an obstetric or medical indication and EM if they delivered between 395 to 420 weeks. The primary outcome was a neonatal composite of perinatal death, neonatal respiratory support, Apgar score ≤ 3 at 5 minutes, and shoulder dystocia. Secondary outcomes included rate of cesarean, select maternal/neonatal outcomes, and number of medical visits >39 weeks as proxy for health care utilization (Table 2). Groups were compared using Chi-square, Fisher’s exact, two sample Student t-test, and Wilcoxon rank-sum tests as appropriate. Multivariable logistic regression models were used to adjust for potential confounders. Of the 1,987 low-risk multiparas meeting inclusion criteria, 555 (28%) underwent eIOL and 1,432 (72%) had EM. Women who underwent eIOL were more likely to be non-Hispanic, married and have private insurance (Table 1). eIOL was associated with decreased risk of neonatal composite morbidity (aOR 0.57, 95% CI: 0.34 – 0.93) compared to EM. Specifically, there was decreased risk of shoulder dystocia in the eIOL group (aOR 0.57, 95% CI: 0.33 – 0.99). There were no perinatal deaths in either group. Cesarean delivery rate was similar among groups (7% eIOL vs. 8.1% EM, aOR 0.77, 95% CI: 0.52 – 1.14). There was no difference between groups with respect to chorioamnionitis, preeclampsia or medical visits > 39 weeks (Table 2). In our patient population, elective induction of labor at 39 weeks among low-risk multiparous women was associated with decreased perinatal morbidity without an increase in cesarean delivery rate. Prospective studies measuring true intent are needed to inform policies regarding eIOL in these women.View Large Image Figure ViewerDownload Hi-res image Download (PPT)