Fetal alcohol syndrome: a Japanese perspective.

To estimate and prevent the effects of prenatal alcohol on the central nervous system (CNS), brain dysfunction in fetal alcohol syndrome (FAS) and fetal alcohol effects (FAE) was compared by both epidemiological and experimental studies. The FAS infants exhibited a more severe degree of CNS involvement than the FAE infants. The CNS involvement features were developmental delay and intellectual impairment in both FAS and FAE. The increased risk of low birth weight and CNS involvement were much more significant in women who were heavy drinkers or alcoholics and smoked. The beneficial effect of supplementary zinc on the fetal cerebrum of FAS or FAE rats was limited, never reaching the unexposed control level. One of the most vulnerable structures in the rat fetus exposed to ethanol in utero was the synaptic formation in the hippocampus. The consistent dysmorphogenesis of synapses during early brain development may be associated with the functional impairment of the CNS in FAS and FAE.