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Fetal Alcohol Syndrome


Kevin C. Dysart

, MD, Nemours/Alfred I. duPont Hospital for Children

Reviewed/Revised Mar 2021 | Modified Sep 2022

Alcohol exposure in utero increases the risk of spontaneous abortion, decreases birth weight, and can cause fetal alcohol syndrome, a constellation of variable physical and cognitive abnormalities.

At birth, infants with fetal alcohol syndrome (FAS) can be identified by small stature and a typical set of facial traits including microcephaly, microphthalmia, short palpebral fissures, epicanthal folds, a small or flat midface, a flat elongated philtrum, a thin upper lip, and a small chin. Abnormal palmar creases, cardiac defects, and joint contractures may also be evident.

After birth, cognitive deficits become apparent. The most serious manifestation is severe intellectual disability Intellectual Disability Intellectual disability is characterized by significantly subaverage intellectual functioning (often expressed as an intelligence quotient < 70 to 75) combined with limitations of adaptive... read more , which is thought to be a teratogenic effect of alcohol given the high number of intellectually disabled infants born to women who have an alcohol use disorder. Fetal alcohol syndrome may be the most common cause of noninherited intellectual disability.

Diagnosis of Fetal Alcohol Syndrome

  • Clinical evaluation

Diagnosis of fetal alcohol syndrome is given to infants with characteristic findings born to women who used alcohol excessively during pregnancy.

No single physical or cognitive finding is pathognomonic; lesser degrees of alcohol use cause less severe manifestations, and the diagnosis of mild cases can be difficult because partial expression occurs. It is often difficult to distinguish the effects of alcohol on the developing fetus from those of other exposures (eg, tobacco, other drugs) and factors (eg, poor nutrition, lack of health care, violence) that affect women who drink excessively.

Treatment of Fetal Alcohol Syndrome

  • Supportive care

There is no treatment for fetal alcohol syndrome. Supportive care should include an appropriate stimulating and nurturing environment. Good nutrition and growth are especially important. Many children with fetal alcohol syndrome will need learning support in school.

Because it is unknown when during pregnancy alcohol is most likely to harm the fetus and whether there is a lower limit of alcohol use that is completely safe, pregnant women should be advised to avoid all alcohol intake. Siblings of an infant diagnosed with fetal alcohol syndrome should be examined for subtle manifestations of the disorder.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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