Neonatal mortality and morbidity were reported over a 4-yr period from 1986-1989 in premature infants weighing less than 1,500 g, 278 of whom were born in the same obstetrico-neonatal unit. Total mortality was 15%, and was higher in premature infants weighing less than 1,000 g (38%) and lower if the gestational age was greater than 27 wk. Mortality was lower in small for gestational age (SGA) infants than in appropriate for gestational age (AGA) infants (5% vs 19%, P less than 0.001), and lower in inborn babies than in outborn (12% vs 19%, P less than 0.02) but only in neonates weighing less than 1,000 g. Neonatal morbidity was mainly due to hyaline membrane disease and cerebral haemorrhage. The incidence of broncho-pulmonary dysplasia was low (4%). These results indicate that gestational age, birth weight and place of delivery play a role in mortality and morbidity in very low birth weight premature infants.