Recent advances in antepartum fetal evaluation have contributed to a marked reduction in fetal deaths in pregnancies complicated by overt diabetes mellitus. To determine the effect of these changes on neonatal morbidity and mortality, a retrospective analysis of complications in 322 infants of diabetic mothers (IDM) in White classes B–R was undertaken. The majority (89 per cent) of the IDM were delivered at term with a mean gestational age of 38 weeks. Neonatal morbidity correlated significantly with gestational age, occurring in 80 per cent of the preterm and 40 per cent of the term infants. The overall incidence of complications was: hyperbilirubinemia 37 per cent, hypoglycemia 31 per cent, hypocalcemia 13 per cent, polycythemia 8 per cent, and necrotizing enterocolitis 2 per cent. Respiratory distress syndrome (RDS) occurred in 9 per cent and congenital malformations in 6 per cent of the infants. Nine infants died, and four of these deaths were due to anomalies. These data indicate that (1) a reduction in fetal mortality has been accompanied by a reduction in neonatal mortality; (2) neonatal morbidity has been decreased but remains significant in the IDM; and (3) congenital anomalies have replaced RDS as a major cause of neonatal death for the IDM.