Fetal alcohol spectrum disorder

• Published in: Canadian Medical Association journal (CMAJ) Vol. 169; no. 11; pp. 1181 - 1185
• Main Authors: Koren, Gideon, Nulman, Irena, Chudley, Albert E, Loocke, Christine
• Format: Journal Article
• Language: English
• Published: Canada CMA Impact, Inc 25.11.2003
• Series: Practice
• Subjects: Adult; Alcohol Drinking - adverse effects; Alcohol Drinking - blood; Alcohol Drinking - psychology; Alcoholism; Attention Deficit and Disruptive Behavior Disorders - etiology; Children of alcoholics; Counseling; Female; Fetal Alcohol Spectrum Disorders - complications; Fetal Alcohol Spectrum Disorders - diagnosis; Fetal Alcohol Spectrum Disorders - prevention & control; Fetal alcohol syndrome; gamma-Glutamyltransferase - blood; Humans; Infant, Newborn; Informed Consent; Meconium - chemistry; Practice; Pregnancy; Treatment
• ISSN: 0820-3946; 1488-2329

At least half of Canadian and American women drink socially1 and half of all pregnancies are unplanned;2 thus, an estimated quarter of all newborns (about 100 000 infants a year in Canada) are exposed to some alcohol during early gestation. Fetal alcohol syndrome (FAS) was originally described as intrauterine and postnatal growth retardation (below the third percentile); specific facial changes (short palpebral fissures [2 standard deviations below normal for age], smooth philtrum and thin vermilion border of the upper lip); and adverse brain effects (mainly mental retardation).3,4 However, during the late 1970s and 1980s, it became apparent that this classic triad of symptoms was relatively uncommon in the offspring of heavy drinkers (occurring in only 4%-5%).5 More often (in 30%-40% of children of heavy drinkers), the brain injury manifests as mild rather than severe cognitive dysfunction and a more subtle and complex pattern of neurobehavioral problems (Box 1) with or without physical features of classic FAS. The broader term "fetal alcohol spectrum disorder" (FASD) has been coined in recent years to encompass the wide range of adverse fetal effects of ethanol - from the classic FAS to its more partial presentations. Overall, it is estimated that FASD affects up to 9.1 of every 1000 babies born in the United States and Canada.6,7 Counselling of women who drank small amounts of alcohol before realizing they had conceived is a complex but important task, because an estimated 25% of all pregnant Canadians fall into this group. About 90% of Canadian women know that alcohol "is not good for the unborn baby" and many believe that even brief and mild exposure to alcohol poses fetal risk.14 Two recent meta-analyses failed to show adverse fetal effects after mild social drinking (up to several drinks a week) by nonalcoholic women.15,16 In contrast, recent studies suggest significant differences in aggressive and externalized behaviour in 6-year-old children with prenatal exposure to as little as 1 alcoholic beverage a week compared with an unexposed control group.17 It is clear, however, that substantial prenatal alcohol exposure - either heavy daily or weekend binge drinking - is the rule in children diagnosed with classic FAS.13 Fetal alcohol syndrome is defined by the classic triad of intrauterine and postnatal growth retardation, specific facial anomalies and adverse brain effects (mainly mental retardation). However, the triad occurs infrequently, and it is now appreciated that a spectrum of clinical problems, both physical and neurobehavioural, stems from alcohol exposure in utero. Koren and colleagues review the range of clinical problems in fetal alcohol spectrum disorder. They also provide information regarding screening questionnaires for diagnosing problem drinking, counselling of women during pregnancy and a novel laboratory test that uses neonatal meconium to detect evidence of maternal drinking.