Most children exposed to high levels of alcohol in the womb do not develop the distinct facial features seen in fetal alcohol syndrome, but many suffer from other problems, according to a study.

Among children examined in the study, these abnormalities of the nervous system involved language delays, hyperactivity, attention deficits or intellectual delays. Researchers with the National Institutes of Health and in Chile documented an abnormality in one of these areas in about 44% of children whose mothers drank four or more drinks a day during pregnancy. In contrast, abnormal facial features were present in about 17% of alcohol-exposed children.

Fetal 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 fetal alcohol syndrome — are classified as fetal alcohol spectrum disorders.

"Our concern is that in the absence of the distinctive facial features, healthcare providers evaluating children with any of these functional neurological impairments might miss their history of fetal alcohol exposure," Devon Kuehn, MD, of the Epidemiology Branch of the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development, said in a news release.

"As a result, children might not be referred for appropriate treatment and services."

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 more than 9,000 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:

• Abnormal facial features: 17% of the alcohol-exposed children, 1% of the unexposed children.

• Delayed growth: 27% of the alcohol-exposed children, 13% of the unexposed children.

• Cognitive delays (including intellectual): 35% of the alcohol-exposed children, 6% of the unexposed children.

• Language delays: 42% of the alcohol-exposed children, 24% of the unexposed children.

• Hyperactivity: 27% of the alcohol-exposed children, 2% of the unexposed children.

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

The study is scheduled for publication in the journal Alcoholism: Clinical and Experimental Research. To read the abstract and access the study via subscription or purchase, visit http://bit.ly/OjNyDP.