The Comparison of Perinatal Outcomes in Early Delivery Versus Postdate Labor

Background Prenatal mortality and morbidity increase after 40 weeks of gestation. The current study aimed at comparing maternal and neonatal outcomes between term and postterm pregnancies. Methods The current prospective cohort study was performed on 1180 singleton, cephalic fetus, and uncomplicated pregnancy cases admitted for labor. Pregnant mothers were divided into 3 groups. Group 1 included 750 cases in 38 to 40 weeks, group 2 included 250 cases in 40 to 41 weeks, and group 3 included 180 cases in over 41 weeks of gestation. Prenatal outcomes were recorded as: fetal distress, meconium passage, meconium aspiration, fetal weight ≥ 4 kg, Apgar score in 1 and 5 minutes, neonatal intensive care unit (NICU) admission, maternal infection, postpartum hemorrhage, and the rate of cesarean section. Results There were significant differences in the rate of fetal distress (P < 0.001), meconium passage (P = 0.001), meconium aspiration syndrome (P < 0.001), Apgar score ≤ 3 at 1 (P = 0.025) and 5 minutes (P < 0.001), admission to NICU (P < 0.001), rate of cesarean section (P < 0.001), and maternal infection (P = 0.001) among the groups. The frequency of fetal distress was lower in group1 compared with group 2 (1.6% versus 4.4%; P = 0.011). Also fetal distress was significantly lower in group 1 than group 3 (1.6% versus 10.9%; P < 0.001). The meconium passage and meconium aspiration syndrome were statistically lower in group 1 compared with group 2 (1.6% versus 8%; P < 0.001 for meconium passage, and 0.9% versus 5.6%; P < 0.001 for meconium aspiration syndrome). Also meconium passage and meconium aspiration syndrome were significantly lower in group 1 compared with group 3 (1.6% versus 13.9%; P < 0.001 for meconium passage, and 0.9% versus 10%; P < 0.001 for meconium aspiration syndrome). The cesarean section was more frequent in group 2 compared with group 1 (24.8% versus 13.6%; P < 0.001) and in group 3 compared with group 1 (33.3% versus 13.6%, P < 0.001). There was no significant difference in the mean fetal weight, fetal weight ≥ 4 kg, and postpartum hemorrhage in females between the 3 groups. Conclusions Late-term and postterm births are associated with higher rates of fetal and neonatal morbidity and maternal risks compared to pregnancy termination before 40 weeks of gestation, and earlier birth induction is recommended in such cases.