During the period 1971 to 1975, 260 women with diabetes mellitus, Classes B through R, were delivered of their infants at Los Angeles County Women's Hospital. The plan of patient management included frequent clinic visits and hospitalization to assure good control. A program of intensive antepartum fetal surveillance was begun at 34 weeks' gestation, with the use of daily 24 hour urinary estriol determinations and a weekly contraction stress test (CST). A lecithin/sphingomyelin ratio was evaluated for all patients before elective delivery. The perinatal mortality rate in these diabetic pregnant women was 46 per 1,000 as compared to 24 per 1,000 in the general population. Only three stillbirths occurred in the diabetic group, none within one week of a negative CST. Congenital malformations were responsible for almost half of the neonatal deaths. There were no deaths due to iatrogenic prematurity or trauma. Mean gestational age at delivery was 37.9 weeks and vaginal delivery was the mode for approximately half of the women. Two thirds of the infants did experience some morbidity.