Fetal alcohol. Teratogenic causes of developmental disabilities

Abstract

Fetal Alcohol Syndrome (FAS) and Fetal Alcohol Effects (FAE) are preventable forms of mental retardation and developmental disability caused by heavy prenatal alcohol exposure. Our best evidence of the overall prevalence of FAS is around 1 in 750 live births, but this figure will vary according to the drinking habits of the community and the diagnostic skills and interests of local physicians. It is likely that many infants are born with FAS or FAE, are never recognized as such, and are never properly diagnosed or evaluated. Other diagnoses that are sometimes confused with FAS include Noonan syndrome and William syndrome. More often, children with milder FAS or FAE go unrecognized. Careful evaluation of possible maternal alcohol abuse during pregnancy can be an important factor in differential diagnosis and proper case management. Alcohol is a teratogenic drug that can produce a wide variety of deficits from prenatal exposure, depending on the dose, timing, and conditions of exposure, as well as on individual differences in sensitivity on the part of the mother and the child. Not all children who are exposed are affected. Perhaps 30-40% of the children of chronic alcoholic mothers who were drinking during pregnancy will have FAS. These children are at high risk for mental retardation or developmental disability. Even within this group, however, there can be large individual differences in eventual outcome. Prognosis involves an interaction between the extent of the damage and the stability and structure of the environment. Children whose mothers were abusing alcohol during pregnancy can be at risk for various learning and attentional problems even without FAS, but in the absence of morphologic effects, the diagnostic and prognostic picture is less clear. Systematic efforts toward both prevention and intervention can assure that each child develops to his or her own best potential.