Antepartum Events and Cerebral Handicap

Abstract

Twenty years ago Penrose, Drillien and others developed the two-population theory to explain the causes of mental retardation (Drillien et al. 1966; Penrose 1983; Zigler 1967). In this model, heredity and sociocultural deprivation are the major causes of mild retardation while brain damage and maldevelopment cause most severe retardation. This two-population model has been challenged in recent years by reports that disorders that might damage fetal brains are as frequent in the histories of mildly as of severely retarded individuals (Costeff et al. 1983; Drillien 1968; Hagberg et al. 1981; Lilienfeld and Pasamanick 1956). The identity of these damaging disorders has not usually been determined, but a few of the retarded children reportedly had mothers who were hypertensive or bled during pregnancy (Broman et al. 1975; Drillien 1968; Hagberg et al. 1981). Other children had placental infarcts, clinical evidences of asphyxia at birth, a history of kernicterus or cyanotic disorders in the neonatal period (Broman et al. 1975; Costeff et al. 1983; Drillien 1968; Drillien et al. 1966; Hagberg et al. 1981).