fetal alcohol syndrome (FAS), pattern of physical, developmental, and psychological abnormalities seen in babies born to mothers who consumed alcohol during pregnancy. The abnormalities include low birthweight, facial deformities, and mental retardation, and there appears to be an association with impulsive behavior, anxiousness, and an inability on the part of the affected children to understand the consequences of their actions. When some but not all of these abnormalities are present, they are referred to as fetal alcohol effects (FAE). FAE has been observed in children of mothers who drank as little as two drinks per week during pregnancy. FAS affects 1 to 2 babies per 1,000 born worldwide. Many require constant lifelong supervision and end up institutionalized because of dysfunction in the family. FAS was first defined as a syndrome in 1973, although it has been observed for centuries. See also alcoholism.

Various congenital disorders in a newborn caused by the mother drinking alcohol during pregnancy. The main symptoms are retarded growth, abnormalities of the central nervous system, and certain face and head abnormalities. The child may be mentally retarded. Behavioral problems (e.g., poor concentration, impulsiveness) are sometimes the only obvious symptoms. The syndrome is common in babies born to chronic alcoholics, but health care organizations now commonly recommend that women cease drinking alcohol entirely while pregnant. Other disorders have been linked to alcohol in breast milk.

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