Expectant Mothers Who Drink On Rise

The speaker paused and repeated his message for emphasis.

"Fetal alcohol syndrome is the most common recognizable cause of mental retardation in the United States. It’s a cause that is totally preventable."

The speaker was Kenneth Lyons Jones of the University of California-San Diego, and his audience was about 100 fellow scientists studying developmental toxicology. They were attending a conference at UW-Madison, and the Friday morning topic was chemically induced birth defects in humans.

Researchers are trying to unravel the molecular mechanisms by which substances such as alcohol disrupt human development. It’s well established that alcohol consumption by pregnant women can cause devastating defects in their babies: low weight, small heads, facial abnormalities, low intelligence, hyperactivity, joint problems.

"You can tie them all in a bundle and they don’t have anywhere near the effect that alcohol does on the unborn baby," Jones said.

Despite the evidence, the number of expectant mothers who admitted drinking alcohol increased from 12.4 percent in 1991 to 16.3 percent in 1995.

Estimates vary wildly. The Center for Disease Control uses the most conservative estimates, which put the range of FAS babies at somewhere between 800 and 4,000 a year. Studies done by the March of Dimes, which advocates for prevention of birth defects, put the number of FAS babies at 5,000 a year and estimate another 50,000 children may have some damage.)

"Unfortunately, we’re not doing a very good job of educating pregnant women about the deleterious effects of alcohol," Jones said.

Scientists suspect the devastation comes from alcohol’s effects on the baby’s brain as it forms facial structures and controls movement in the womb. But scientists don’t know why some women drink a lot and have apparently normal babies, while others drink less but damage their infants.

"There is no safe amount for all women to drink during pregnancy," Jones said. Some risk factors are known, but genetic factors may be critical. Metabolism may play a role.

(Known risk factors are a mother older than 30, of low socio-economic status and of ethnic background, especially African American or American Indian.)

In a conversation after his speech, Jones said research findings may help educators craft better messages about the dangers of drinking while pregnant.