Elective induction versus spontaneous labor: a retrospective study of complications and outcome

This retrospective study was undertaken to identify whether electively induced labor places the mother or her fetus at increased risk as compared with her spontaneous labor cohort.

This study compares the labor, delivery, and fetal outcome of 253 parturients in which labor was electively induced with 253 matched controls who began labor spontaneously. All patients were delivered at Huntington Memorial Hospital in Pasadena, California, during the calendar year 1990. The patients were between 37 and 41 weeks' gestation and had no medical or obstetric conditions necessitating induction. The cases and controls were matched for age group, parity, gestational age, and delivering obstetrician.

Epidural anesthesia was used in 83.8% of patients in the induction group versus 55.7% in the spontaneous group. Patients with labor induced had a shorter first stage of labor. Meconium staining was found significantly more often in the spontaneous group than in the induced group (16.2% vs 6.7%). This contributed to a greater rate of neonatal consultations in the spontaneous labor group. Although cesarean section rates between the two groups were similar, nulliparous patients in the induction group with an estimated Bishop score of less than or equal to 5 had a 50% cesarean section rate. Iatrogenic prematurity was not encountered. No differences existed between the two groups with respect to intrapartum maternal complications, fetal complications, or postpartum complications.

When compared with spontaneous labor, elective induction of labor at term does not appear to pose an increased risk to the mother or her fetus in a carefully selected patient population. However, elective induction of labor in a nulliparous patient with an unfavorable cervix should be discouraged.