The relationship between the consumption of alcohol and congenital defects has long been part of conventional wisdom. In the Book of Judges (13:7) an angel tells the wife of Manoah, "Behold, thou shalt conceive and bear a son; and now drink no wine or strong drink . . ." (The son was Samson, whose great strength became legendary.) In Carthage and Sparta the bridal couple were forbidden to drink wine on their wedding night so that defective children might not be conceived. In 18th-century England, the College of Physicians called gin a cause of "weak, feeble and distempered children" and petitioned Parliament to control the distilling trade.
In 1899, William Sullivan, a physician to a Liverpool prison, made a careful study that anticipated the rigorous control required by scientific testing today. He compared the offspring of heavy-drinking women with the offspring of their nondrinking female relatives and reported that the rate of infant mortality and stillbirth was two and a half times higher among the children of the drinking mothers. He also observed that several women prisoners who had previously borne infants with severe and sometimes fatal defects had borne healthy infants while they were imprisoned and forced to abstain from alcohol.
Within the last few years conventional wisdom has been repeatedly reinforced by scientific investigations. In 1973, dysmorphologists Kenneth Jones and David Smith, of the Child Development and Mental Retardation Center at the University of Washington in Seattle, supported by the National Institute of Child Health and Human Development, described a distinct pattern of abnormalities in children of alcoholic mothers that they called the fetal-alcohol syndrome (FAS). Children afflicted with FAS can have a composite of defects, including growth deficiency, particularly in length; mental retardation; craniofacial abnormalities, such as microcephaly and small palpebral fissures; and limb and heart malformations.
Soon after the description of FAS was published, the Seattle group learned of a French study (Lemoine, 1968) in which the same constellation of symptoms was observed. Since then, reports of new research from the United States and elsewhere have steadily augmented the rolls of known patients. The incidence of FAS is now estimated as between one and two live births per 1,000, with the incidence of partial expressions at approximately three to five live births per 1 ,000.
Disturbances of intellectual function are the most serious manifestations of maternal alcohol abuse, affecting the vast majority of FAS children. The greater the alcohol consumption by the pregnant woman, the greater the likelihood of multiple symptoms. Milder consumption of alcohol has been linked to minimal brain dysfunction - subtle but more frequent abnormalities of attention, behavior, and learning.
Alcohol readily crosses the placenta and remains in the fetus for long periods in high concentration. It has recently been established that the fetus has a low level of alcohol dehydrogenase, the enzyme necessary for the metabolism of alcohol. This finding suggests that the teratogenic alcohol has a much longer period of activity within the fetus than in the adult.
The future for affected children is dim. Surgical correction of some heart defects may be feasible; some heart-cavity closures heal without treatment; some adjustments may be possible for hip and joint disabilities. But the smallness of these babies generally persists despite good nutrition. They continue to exhibit slow motor and mental development. They do not catch up with normal children.
Scientists have not yet determined precisely the timing and degree of risk to the fetus of maternal drinking. In Seattle, studies by James Hanson, Ann Streissguth, and David Smith suggest that the month preceding recognition of pregnancy appears to be of particular danger. Moreover, occasional binge drinking and moderate drinking appear to be implicated along with heavy and steady consumption of liquor. Safe levels of drinking are not known, nor is the factor of individual variability understood.
Because factors other than alcohol (such as nicotine and nutrition) may confound human studies, animal studies are invaluable. Joan Martin in Seattle is working with animals to determine what dosage of alcohol is compatible with viable offspring, free of skeletal abnormalities. These animals are subsequently watched for maldevelopment and behavioral sequelae. Also at the Retardation Center in Seattle, Donald Pious and his colleagues are studying growth deficiencies of both genetic and environmental origins. They have completed the first in-vitro study of a growth deficiency of prenatal onset, the cause of which, alcohol, is purely environmental. They are also studying the dose-response relationship.
Responsibility for the support of research to address these issues and learn why and how alcohol is detrimental to the fetus is shared by the NICHD and the National Institute on Alcoholism and Alcohol Abuse.
The NICHD considers FAS, first of all, a serious problem in pediatrics. It is one that affords a good measure of hope. Through accurate understanding of the intrauterine effects of alcohol and through widespread public awareness, this major cause of mental retardation could be greatly reduced. Beyond this, the fetal-alcohol syndrome can serve as a model system for studying congenital malformations.