em (CNS). To meet the clinical case definition, the child must have symptoms in each of the following three categories: (1) growth deficiency in both the prenatal and postnatal periods: (2) abnormalities in facial and skull structure, including small eye openings (i.e., short palpebral fissures), alterations in nose and forehead structure, an absent or elongated groove between the upper lip and nose (i.e., philtram), a thin upper lip, a flattened midface, and underdevelopment of the upper or lower jaw; and (3) CNS deficits, such as mental retardation and behavioral problems (Sokol and Clarren 1989). Of these symptoms, the facial abnormalities are the most characteristic of FAS, whereas the CNS anomalies have the most significant effect on overall development. Separately, each of these features is defined as an alcohol-related birth defect (ARBD) or a fetal alcohol effect.
The features associated with FAS may change with age, complicating the diagnosis. Before age 2, CNS dysfunction is difficult to assess, and the classic facial abnormalities [ILLUSTRATION OMITTED] may not be clearly evident. At older ages, growth deficits are offset by the adolescent growth spurt as well as normal changes in facial length and width associated with maturation. Because of these changes, growth deficits and facial features become less apparent after puberty, and without prepubertal photographs and reliable growth records, FAS may be difficult to diagnose in adolescents or adults.
Accurately assessing fetal alcohol exposure may prove even more difficult. To obtain correct information regarding the quantity of alcohol consumed as well as the timing and duration of alcohol use during pregnancy, clinicians and researchers need reliable methods to determine alcohol exposure. Although biological tests are available to measure the amount of alcohol consumed, these tests reflect use over a very short time period and do not allow estimates of the pattern or d...