Maternal and neonatal outcomes in electively induced low-risk term pregnancies

Abstract

Elective induction of labor has been discouraged over concerns regarding increased complications. We evaluated the mode of delivery and maternal and neonatal morbidities in low-risk patients whose labor was electively induced or expectantly managed at term. This was a retrospective cross-sectional study from 12 US institutions (19 hospitals), 2002 through 2008 (Safe Labor Consortium). Healthy women with viable, vertex singleton pregnancies at 37-41 weeks of gestation were included. Women electively induced in each week were compared with women managed expectantly. The primary outcome was mode of delivery. Of 131,243 low-risk deliveries, 13,242 (10.1%) were electively induced. The risk of cesarean delivery was lower at each week of gestation with elective induction vs expectant management regardless of parity and modified Bishop score (for unfavorable nulliparous patients at: 37 weeks= 18.6% vs 34.2%, adjusted odds ratio, 0.40; [95% confidence interval, 0.18-0.88]; 38 weeks= 28.4% vs 35.4%, 0.65 [0.49-0.85]; 39 weeks= 23.6% vs 38.5%, 0.47 [0.38-0.57]; 40 weeks= 32.3% vs 42.3%, 0.70 [0.59-0.81]). Maternal infections were significantly lower with elective inductions. Major, minor, and respiratory neonatal morbidity composites were lower with elective inductions at ≥38 weeks (for nulliparous patients at: 38 weeks= adjusted odds ratio, 0.43; [95% confidence interval, 0.26-0.72]; 39 weeks= 0.75 [0.61-0.92]; 40 weeks= 0.65 [0.54-0.80]). Elective induction of labor at term is associated with decreased risks of cesarean delivery and other maternal and neonatal morbidities compared with expectant management regardless of parity or cervical status on admission.