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Fetal Alcohol Syndrome

A Historical And Research Perspective Of Fas

In 1899, the first observation connecting children of alcoholic mothers to the associated risks was shown in a study comparing these children to children of non-alcoholic relatives. However, alcohol consumption during pregnancy was not considered to be a risk to the fetus until it was formally concluded as a risk factor in 1973. During the late 1960s, federally funded studies investigating causes of mental retardation and neurological abnormalities did not include alcohol as a possible teratogen. In fact, intravenous alcohol drips were used to help prevent premature birth. However, by the 1970s, concerns began to grow regarding the adverse effects of toxic substances and diet during pregnancy. Cigarette smoking was known to produce babies of low birth-weight and diminished size and malnutrition in pregnant women seriously impaired fetal development. When the effects of prenatal exposure to alcohol were first discovered, studies were launched internationally to determine long-term effects. It is now considered that alcohol consumption during pregnancy causes neurological and behavioral problems that affect the quality of life for the child.

In 1974, a United States study compared the offspring of 23 alcoholic mothers to 46 non-drinking mothers with participants that were defined using the same general characteristics such as geographic region, socioeconomic group, age, race, and marital status. By the age of seven years, children of alcoholic mothers earned lower scores on math, reading, and spelling tests, and lower IQ scores (an average of 81 versus 95). Although 9% of the children born to non-drinking mothers tested 71 or lower 44% of children of alcoholic mothers fell into this range. Similar percentages of reduced weight, height, and head circumference were also observed. A Russian study in 1974 demonstrated that siblings born after their mothers became alcoholics had serious disabilities compared to children born before the mother became an alcoholic. Fourteen of the 23 children in this category were considered mentally retarded. A 1982 Berlin study reported for the first time that FAS caused hyperactivity, distractibility and speech, eating, and sleeping disorders. In a study that began in 1974 and followed subjects until the age of 11 years, children of "low risk" mothers who simply drank "socially" (most not even consuming one drink per day after becoming pregnant) found deficits in attention, intelligence, memory, reaction time, learning ability, and behavior were often evident. On average, these problems were more severe in children of women who drank through their entire pregnancy than those who stopped drinking. A 1988 study confirmed earlier findings that the younger child of an alcoholic mother is more likely to be adversely affected than the older child. In 1990, a Swedish study found that as many as 10% of all mildly retarded school-age children in that country suffered from FAS.

Until recently, most studies regarding FAS have been with children. In 1991, a major report done in the United States on FAS among adolescents and adults aged 12–40 years with an average chronological age of 17 years revealed that physical abnormalities of the face and head as well as size and weight deficiencies were less obvious than in early childhood. However, intellectual variation ranged from severely retarded to normal. The average level of intelligence was borderline or mildly retarded, with academic abilities ranging between the second and fourth grade level. Adaptive living skills averaged that of a seven-year-old, with daily living skills rating higher than social skills.

Since the 1990s, studies that involve the specific effects of alcohol on brain cells have been undertaken. In order to understand the specific mechanisms that lead the developmental abnormalities, studies in 2002 demonstrated that in rodents, the time of greatest susceptibility to the effects of alcohol coincides with the growth-spurt period. This is a postnatal period in rodents but extends from sixth months of gestation to several years after birth in humans. It is during this time that alcohol can trigger massive programmed brain cell death and appears to be the period in which alcohol can have the greatest damaging effects on brain development.


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Science EncyclopediaScience & Philosophy: Ferroelectric materials to Form and matterFetal Alcohol Syndrome - Alcohol As A Teratogen, A Historical And Research Perspective Of Fas, Diagnosis And Prevention