The effect of type of delivery on neonatal outcome in singleton infants of birth weight of 1,000 g or less.

To evaluate the relationship between management of delivery and neonatal outcome in singleton neonates with birth weights between 501 and 1,000 g, a retrospective analysis was performed. In the 54-month period ending June 30, 1981, a total of 109 singleton neonates were born at Vanderbilt University Hospital, Nashville, Tenn, with birth weights between 501 and 1,000 g, 31 weighing 501 through 750 g, and 78 weighing 751 through 1,000 g. The overall neonatal survival rate was 60%, 39% in the group weighing 501 through 750 g and 69% in the group weighing 751 through 1,000 g. In terms of morbidity and mortality, there was no difference between neonates delivered by cesarean section compared with those delivered vaginally. The only significant factor found relating to neonatal mortality was the occurrence of labor. In the 17 newborns delivered without occurrence of labor, the frequency of neonatal death was significantly decreased, although this difference may be caused by differing risk factors in the infants delivered without occurrence of labor. When labor was present and the fetus had a cephalic presentation, cesarean section was not found to be superior to vaginal delivery in terms of neonatal morbidity or mortality for neonates of 1,000 g or less.