Cognitive changes may be only sign of foetal alcohol exposure

Most children exposed to high levels of alcohol in the womb do not develop the distinct facial features seen in foetal alcohol syndrome, but instead show signs of abnormal intellectual or behavioural development, according to a study by researchers at the National Institutes of Health and researchers in Chile.

These abnormalities of the nervous system involved language delays, hyperactivity, attention deficits or intellectual delays. The researchers used the term s functional neurologic impairment to describe these abnormalities. The study authors documented an abnormality in one of these areas in about 44 percent of children whose mothers drank four or more drinks per day during pregnancy. In contrast, abnormal facial features were present in about 17 percent of alcohol exposed children.

Foetal alcohol syndrome refers to a pattern of birth defects found in children of mothers who consumed alcohol during pregnancy. These involve a characteristic pattern of facial abnormalities, growth retardation, and brain damage. Neurological and physical differences seen in children exposed to alcohol prenatally— but who do not have the full pattern of birth defects seen in foetal alcohol syndrome—are classified as foetal alcohol spectrum disorders.

“Our concern is that in the absence of the distinctive facial features, health care providers evaluating children with any of these functional neurological impairments might miss their history of foetal alcohol exposure,” said Devon Kuehn, M.D., of the Epidemiology Branch of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the NIH institute involved in the study. “As a result, children might not be referred for appropriate treatment and services.”

The Centres for Disease Control and Prevention provides information on the treatments for FASD.

Dr Kuehn conducted the study with NICHD colleagues Tonia C. Carter, Ph.D., Mary R. Conley and Jim Mills, M.D, as well as researchers at the National Heart, Lung and Blood Institute, the National Capital Consortium, in Bethesda, Md., and the University of Chile in Santiago.

Their findings appear online in Alcoholism: Clinical and Experimental Research.

The research was conducted as part of a long-term study of heavy drinking in pregnancy known as the NICHD–University of Chile Alcohol in Pregnancy Study. To conduct the study, the researchers asked over 9000 women at a community health clinic in Santiago, Chile about their alcohol use during pregnancy. They found 101 pregnant women, who had four or more drinks per day during their pregnancies and matched them with 101 women having similar characteristics but who consumed no alcohol when they were pregnant. After these women gave birth, the researchers evaluated the infants’ health and conducted regular assessments of their physical, intellectual and emotional development through age 8.

The researchers documented differences in the rate of children affected in the following areas:

Some of the women with heavy drinking habits also engaged in binge drinking (5 or more drinks at a time). Even though these women already had high levels of alcohol consumption, the researchers found that this habit increased the likelihood of poor outcomes for their children.

Source: National Institutes of Health