Perinatal factors and adverse outcome in extremely low birthweight infants.

Perinatal factors associated with death or disability at 2 years were identified in an inborn cohort of 196 live births with a birth weight of 500-999 g. Antepartum haemorrhage, multiple pregnancy, breech presentation, perinatal asphyxia, hypothermia on admission, hyaline membrane disease, persistent pulmonary hypertension, severe respiratory failure, and intraventricular haemorrhage were associated with increased mortality. Factors associated with increased survival included maternal hypertension, caesarean birth, increasing maturity or size at birth, female sex, and fetal growth retardation. Stepwise multiple discriminant function analysis showed that six factors correctly classified the outcome in 83% of infants: intraventricular haemorrhage was the most important factor followed by the presence of acidosis and hypoxia in the early neonatal period, birth weight, pre-eclamptic toxaemia, and caesarean birth. This study also showed that intraventricular haemorrhage, seizures, antepartum haemorrhage and delay in regaining birth weight were associated with increased disability among survivors.