The Stockholm Neonatal Project: neonatal mortality and morbidity at the Children's Centre, Karolinska Hospital.

Two hundred and ninety-one very-low-birth-weight (VLBW) infants were studied prospectively during the period of 1988-1993. All inborn VLBW infants and most of the VLBW infants born in Greater Stockholm and requiring neonatal intensive care were included in this study. The overall mortality was 17.5% and the mortality in the group with the lowest gestational age at birth, i.e. 23-24 weeks, was 25%. The mortality for boys was higher than for the girls. The mode of delivery, i.e. vaginal versus caesarean section and multiple birth, did not seem to affect the mortality rate. Respiratory insufficiency and/or cerebral complications were the most common cause of neonatal death. Patent ductus arteriosus was found in 35% of the infants, of whom 43% needed surgical ligation. One-third of infants with retinopathy of prematurity (30/92) required cryotherapy.