Childhood neurological disorders in twins.

In order to examine neurological outcome in twins, a multi-centre prospective cohort study of infants was used. Women entered at the first prenatal visit, with follow-up of offspring to the age of 7 years. Outcome measures were death, cerebral palsy, seizure disorders including neonatal, febrile or nonfebrile, and intelligence quotient. Among a total of 52,364 livebirths, there were 1079 twins. Overall, rates of fetal or neonatal death and cerebral palsy were higher in twins. Neonatal and febrile seizures occurred with similar frequency in twins as in singletons. Although twins were much more likely than singletons to be low in birthweight, twins < 2500 g were not at higher risk for cerebral palsy than low birthweight singletons. The risk of cerebral palsy and of nonfebrile seizure disorders was similar in monozygous and dizygous pairs, and in like-sex and unlike-sex pairs. Death of one twin was associated with higher rates of cerebral palsy and of nonfebrile seizure disorders in survivors, but not with lowered intelligence. Data from this cohort suggest that low birthweight and survival status of the co-twin are dominant predictors of childhood neurological morbidity in twins.