619 Timing of induction of labor has no association with labor or delivery complications

Abstract

To assess labor, delivery, maternal and neonatal complications associated with timing of induction of labor. This was a secondary analysis of 2 randomized trials involving 6 cervical ripening methods. The inclusion criteria were patients with obstetric or medical indication for IOL, singleton gestation and unfavorable cervix. The 6 cervical ripening methods included: Foley + 4 mg compound PGE (gel) vs Foley + 10 μg misoprostol (oral) vs 100 μg misoprostol (oral) vs 10 mg dinoprostone (pessary) vs Athad + Prepidil 0.5 mg (gel) vs 25 μg then 50 μg misoprostol (intra-vaginal). For this analysis, 905 patients were included and divided into 4 groups according to time period of labor induction: Early Day (ED)- 06:00 to 12:00; Late Day (LD)- 12:00 to 18:00; Early Night (EN)- 18:00 to midnight; Late Night (LN)- midnight to 06:00. The demographic, obstetric, labor and delivery characteristics and neonatal outcomes were compared. Demographic were significant for mean maternal age, BMI categories, mean gestational age and gestational age categories (LN had largest percent < 37 weeks), There were non-significant between the 4 groups for percent of nulliparous, ethnicity, maternal weight, BMI. There were significant differences for indications of induction with more preterm and hypertensive disorders at LN; however the percent of bishop score < 6 was similar. The most common indication for induction is hypertensive disorders follow by oligohydramnios and post-term. The duration of medical induction, 1st and 2nd stage of labor were similar. The mode of delivery and cesarean indications were similar. The rate of meconium, chorioamnionitis and uterine tachysystole were similar. Neonatal outcomes were similar for gender, birth-weight, umbilical cord pH, Apgar < 7 and NICU admission. IOL at LN had younger mom and more at < 37 weeks with hypertensive disorders. There were no difference in duration in medical induction, 1st and 2nd stage of labor, and mode of delivery across the 4 IOL periods. There were differences in labor or neonatal complications associated with timing of IOL.