Cesarean section was not associated with mortality or morbidities advantage in very low birth weight infants: a nationwide cohort study.

This study investigated the role of cesarean section (CS) in mortality and morbidity of very-low-birth-weight infants (VLBWIs) weighing less than 1500 g. This nationwide prospective cohort study of the Korean Neonatal Network consisted of 9,286 VLBWIs at 23-34 gestational weeks (GW) of age between 2013 and 2017. The VLBWIs were stratified into 23-24, 25-26, 27-28 and 29-34 GW, and the mortality and morbidity were compared according to the mode of delivery. The total CS rate was 78%, and was directly proportional to gestational age. The CS rate was the lowest at 61% in case of infants born at 23-24 GW and the highest at 84% in VLBWIs delivered at 29-34 GW. Contrary to the significantly lower total mortality (12%) and morbidities including sepsis (21%) associated with CS than vaginal delivery (VD) (16% and 24%, respectively), the mortality in the 25-26 GW (26%) and sepsis in the 27-28 GW (25%) and 29-34 GW (12%) groups were significantly higher in CS than in VD (21%, 20% and 8%, respectively). In multivariate analyses, the adjusted odds ratios (ORs) for mortality (OR 1.06, 95% CI 0.89-1.25) and morbidity including sepsis (OR 1.12, 95% CI 0.98-1.27) were not significantly reduced with CS compared with VD. The adjusted ORs for respiratory distress syndrome (1.89, 95% CI 1.59-2.23) and symptomatic patent ductus arteriosus (1.21, 95% CI 1.08-1.37) were significantly increased with CS than VD. In summary, CS was not associated with any survival or morbidity advantage in VLBWIs. These findings indicate that routine CS in VLBWIs without obstetric indications is contraindicated.