Factors identified during the neonatal period associated with risk of cerebral palsy

To identify factors during the neonatal period that are associated with the subsequent development of cerebral palsy (CP).

Case-control study.

Ten hospitals in Victoria, Australia.

Cases were babies with moderate or severe CP identified from the Victorian Cerebral Palsy Register. Controls were matched with cases for year of birth, plurality, sex, birthweight, gestation and hospital of birth.

A range of neonatal variables was compared between cases and controls, initially in a univariate analysis and subsequently in a logistic regression. The analysis was matched where possible. Where missing data prevented a matched analysis, an adjusted unmatched analysis was performed.

Those neonatal factors making an independent contribution to the risk of CP in both term and preterm infants.

Among babies born at term, 73% of cases and 2% of controls were identified by at least one of the following factors: seizures, congenital abnormalities of the brain and elsewhere, 'other lesions', abnormal muscle tone and meconium aspiration. Among babies born preterm, 68% of cases and 26% of controls were identified by the following factors: seizures, intraventricular haemorrhage, periventricular leukomalacia, 'other lesions' and abnormal muscle tone.

The neonatal factors which best identify neonates who will subsequently develop CP are different for term and preterm babies. Babies born at term are identified more efficiently than those born preterm. Among term babies especially, some of these factors are clearly of a long-standing nature and are not associated with delivery.