Some babies who do not have full-blown fetal alcohol syndrome can still develop IQ problems, a new study indicates.

Mothers who drink heavily during pregnancy put their babies at risk of fetal alcohol syndrome (FAS), which can lead to growth retardation, and long-term mental, developmental and behavioral problems. Some babies with FAS also develop distinctive facial features, such as a flat midface, and thin upper lip.

While not every baby born to heavy drinkers develops FAS, they can still end up with a low IQ stemming from their exposure to alcohol, investigators at Wayne State University in Detroit, Michigan have now found.

“Even kids without the full fetal alcohol syndrome may have problems with IQ,” lead author Dr. Sandra W. Jacobson told AMN Health. “These children slip by us because we don’t recognize the ‘face’” of FAS, she added.

Certain factors appeared to increase the risk of alcohol-related IQ problems, Jacobson and her colleagues report in the journal Alcoholism: Clinical and Experimental Research.

Specifically, they found that children whose mothers were 30 or older, or had a more severe drinking problem, and children raised in an intellectually non-stimulating home environment, appeared to be at particular risk of alcohol-related problems at age 7.

These findings suggest that all babies born to heavy drinkers should be watched closely, even if they show no signs of FAS, an expert told Reuters Health.

“Children of moderate to heavy drinkers should all be followed,” said Dr. Lynn T. Singer of Case Western Reserve University in Cleveland, Ohio, who was not an author on the study.

Singer added that even though certain babies appear to be more vulnerable to the long-term effects of alcohol exposure in the womb, “it doesn’t mean if you don’t have those factors, you’re safe,” she cautioned.

Many clinicians have believed that babies born to heavy drinkers, but did not show signs of FAS, might develop only “mild problems” stemming from their alcohol exposure.

To investigate whether these so-called “mild” effects of alcohol influenced some children more than others, Jacobson and her colleagues followed 337 inner-city African-American children until they were 7-1/2, noting how much their mothers drank during their pregnancies.

In an interview, Jacobson explained that only one mother said she drank alcohol every day during her pregnancy. Consequently, most of the damage from alcohol likely comes from concentrated drinking, such as when expecting mothers down 5 glasses of alcohol at a party, she said.

SOURCE: Alcoholism: Clinical and Experimental Research, November 2004.