Collaborative study of very-low-birthweight infants: Techniques of perinatal care and mortality.

The neonatal units in two large maternity hospitals collaborated in a study of 440 liveborn infants weighting 500-1500 g born in 1977 and 1978: 377 (85.7%) were born in hospital. The overall survival rate was 70.5%, with a range of 67.5% to 71.5% for the inborn and outborn categories of infants in each hospital. In hospital A the survival rate of infants weighing greater than or equal to 1100 g was higher than that in hospital b, whereas the survival rate of infants weighing less than 800 g was higher in hospital B. Obstetric risk factors and obstetric management differed little between the hospitals, but there were several important differences in paediatric management; in particular, hospital B (with a better survival rate of infants weighing under 800 g) used ventilatory support and parenteral feeding much more frequently.