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Fetal Alcohol Syndrome

  • Definition

    In 1973, Jones and Smith coined the term "fetal alcohol syndrome" (FAS) to describe a pattern of abnormalities observed in children born to mothers who drink alcohol.

    Alcohol has been found to be acutely toxic to the developing fetus.


    Evidence suggests that the morphologic and functional deficits observed in children with fetal alcohol syndrome are related to two concepts - the timing of the toxic event ("critical period") and the peak alcohol concentrations ("critical dosage"). Alcohol itself is highly toxic to the fetus.


    The specific mechanisms through which alcohol exerts its devastating effects remains speculative. These mechanisms may include a direct toxic effect on fetal cells, a disruption of prostaglandin metabolism, and fetal hypoxia secondary to compromised blood flow to the placenta.

    In addition, alcohol or its metabolites may impair placental transfer of essential amino acids and zinc, both necessary for making proteins, which accounts for intrauterine growth retardation.

    All mothers who drink alcohol are at risk of causing fetal alcohol syndrome in their unborn child.


    Alcohol and Birth Defects

    mental retardation is the most common and serious birth defect associated with FAS. The average IQ for persons with FAS is 67, and one-half of all those afflicted with the syndrome have an IQ of less than 70. Thus, most of these persons are in the mildly retarded range (50 to 70).

    Perhaps the most notable defects in FAS involve the face and eyes. In general, these defects are obvious and include facial bone hypoplasia (under-development), a long, underdeveloped philtrum (the groove in the middle of the upper lip), a thin upper lip, a short nose, and ptosis (drooping of the eyelids).

    Although the typical facial features may not be as apparent during the newborn period, they become more prominent as the infant develops. As these children grow into young adulthood, however, the facial abnormalities become more subtle and thereby contribute to the difficulty of recognizing FAS in older persons.

    With these physical abnormalities come sensory deficits that frequently involve vision, hearing and speech. Hyperacusis (abnormal acuteness of hearing) is common in infants, and approximately one third of these infants have a conductive hearing loss and another one-third have a sensorineural hearing loss.

    More than 90 percent of infants with FAS have delays in receptive and expressive language development.


    Despite warnings about the devastating effects on their unborn child, some women continue to drink during pregnancy.

    Treatment of women who continue to drink during pregnancy consists of counseling, with an emphasis on prohibiting alcohol consumption, and explanations of the dangers of alcohol use during pregnancy, including the possibility of infants born with FAS.

    The management of infants with FAS is difficult, since no specific therapy exists. In general, the prognosis is poor.


    How does alcohol harm the fetus?

    How much alcohol is harmful?

    Is there a risk of birth defects?

    What birth defects are possible?

    How can the risks involved be minimized?

    Where can I get treatment for alcohol abuse?

    The only sure way to prevent this problem is to abstain from alcohol during the entire length of a pregnancy.

    The essential features of prevention for FAS are early recognition of risk and appropriate educational intervention.

    Most women are reluctant to report the volume of alcohol they consume; moreover, if there is a positive history of alcohol consumption, the volume is usually underestimated. For these reasons, it is difficult to determine the exact amount of alcohol ingested during a woman's pregnancy.

    Pregnancy can be an opportunity to address alcohol abuse openly and to seek treatment since there are at least two lives affected.