Cerebral Palsied Twins

Abstract

Forty-four pairs of twins are described in which one member of each pair suffers from cerebral palsy. They are compared with 44 control twin pairs. The 44 cerebral palsied twins were taken from 488 consecutive cases of cerebral palsy, giving an incidence of twinning of 9%, the highest incidence being among diplegic patients. Less than half of the twins of cerebral palsied patients were surviving and well,the majority were stillborn (including those delivered as macerated fetuses), died neonatally or within the first year of life or were mentally handicapped. In pairs in which one member was cerebral palsied and the other was stillborn or had died in early infancy, the ratio of like-sexed to unlike-sexed pairs was greater than would be expected. There was an excess of first-born cerebral palsied twins and second-born stillborn or dead twins. The average birth weight of the cerebral palsied patients was less than that of their surviving healthy twins and of the control twins; the stillborn or dead twins had the lowest average birth weight of all groups and were all premature. The maturity of the cerebral palsied twins, based on the estimated period of gestation, was considerably less than that of the control twins. The incidence of abnormal pregnancy and parturition was no greater in the cerebral palsied group than in the control group; the ages of the mothers at the time of delivery were no greater than expected. The cerebral palsied patients showed more abnormal neonatal signs than did their surviving twins and the control twins. The casualty rate among the nine pairs of probable uniovular twins was higher than that among the 25 pairs of probable binovular twins, three pairs of uniovular twins in which both members survived are described. The incidence of mental impairment, visual, auditory and speech defects was considerably higher among the cerebral palsied twins than among the controls. In the majority of cerebral palsied twins the cerebral defect is unrelated to abnormalities of pregnancy and parturition or to maternal age. The most important factor appears to be low birth weight due either to multiple pregnancy alone, or to a combination of multiple pregnancy and preexisting fetal abnormality.