Timing of elective Cesarean section and neonatal outcomes in term singleton deliveries: A single-center experience.

Objective This study aimed to evaluate the timing of elective Cesarean sections at 37-41 weeks from a tertiary hospital in Japan. The primary outcome was the rate of adverse neonatal outcomes, especially focusing on neonates delivered at 38 weeks of gestation. Study design The study population was drawn from singleton pregnancies delivered following planned Cesarean birth at the Fukuda Hospital from 2012 to 2019. Information on deliveries was obtained from the hospital database, which contains clinical, administrative, laboratory, and operating room databases.  Results After excluding women with chronic conditions, maternal complications, indications for multiple births, or a neonate with an anomaly, 2208 neonates remained in the analysis. Among adverse neonatal outcomes, the rate was significantly higher in neonates delivered at 37 weeks of gestation (unadjusted odds ratio 13.22 [95% confidence interval {CI} 6.28, 27.86], P < 0.001) or 38 weeks of gestation (unadjusted odds ratio 1.82 [95% CI 1.04, 3.19], P = 0.036) compared to neonates delivered at 39-41 weeks. The adjusted risk of any adverse outcome was significantly higher at 38+0-1 weeks (adjusted odds ratio [OR] 2.40 [95% CI 1.35, 4.30], P = 0.003) and 38+2-3 weeks (adjusted OR 1.89 [95% CI 1.04, 3.44], P = 0.038) compared to neonates delivered at 39-41 weeks, respectively. Conclusion Our findings suggest that elective Cesarean sections might be best scheduled at 39 weeks or later. When considering a Cesarean at 38 weeks, it appears that 38+4 weeks of gestation or later could be a preferable timing in the context of reducing neonatal risks. However, as the composite outcome includes mostly minor conditions, the clinical significance of this finding needs to be carefully interpreted.