Does cesarean section prevent mortality and cerebral ultrasound abnormalities in preterm newborns?

Despite the increased use of the cesarean section (CS), the rates of cerebral palsy, a frequent consequence of brain damage, have remained stable over the last decades. Whether an actual decrease in cerebral palsy has been masked by increased survival of infants delivered by CS or not, remains undefined. To investigate the role of CS, we compared risks of mortality and brain damage, as defined by ultrasound (US) abnormalities, in preterm newborns by mode of delivery.

Information on fetal, maternal, and neonatal risk factors was collected from the paired clinical records of preterm newborns and mothers. Crude and adjusted odds ratios (OR) of mortality and ultrasound abnormalities, according to mode of delivery (i.e., vaginal, elective CS, and emergency CS) were calculated. All the analyses were controlled for possible confounding by indication.

In newborns of gestational age <32 weeks, no effect of CS on cerebral US abnormalities was found (OR 0.71 and 0.73 for emergency CS and elective CS, respectively). None of the maternal and neonatal factors were associated with both cerebral US abnormalities and mode of delivery. Among newborns of gestational age >or=32 weeks, after controlling for known and potential confounders in a multivariate model, the adjusted ORs remained close to one for both elective CS and emergency CS.

CS does not reduce overall mortality in preterm newborns. No protective effect of CS on US abnormalities was found after stratifying by gestational age and controlling for possible confounding. These results do not encourage the widespread use of CS in preterm labor.