Effect of cesarean section on outcome in high- and low-risk very preterm infants.

The effect of mode of delivery on the survival and morbidity of 24- to 32-week infants (500-1500 g) was studied in 262 consecutive deliveries. The study population was divided into high-risk (e.g., hypertension) and low-risk (e.g., incompetence of the cervix) groups by evaluation of risk factors. 194 very preterm newborn were classified as high risk and 68 as low risk. In both groups the perinatal outcome of vaginal delivery and cesarean section delivery was compared. Cesarean section was associated with a highly significantly improved survival rate in the high-risk group, but was not associated with differences in fetal outcome in the low-risk group. The results of this study do not support primary cesarean section as the method of delivery for all very preterm fetuses.