Most moms-to-be know that heavy drinking during pregnancy is dangerous to an unborn child's health. But what about a glass of wine or a mixed drink here and there? A controversial study published Tuesday in the Journal of Epidemiology and Community Health is the latest to suggest that light consumption of alcohol may not be harmful to the baby's physical, emotional and cognitive development.
But many doctors are worried, saying the study could be misinterpreted as a green light to imbibe.
"You can walk on a railroad track and not be hit by a train, but that doesn't mean it's a safe thing to do," said Dr. Michael Katz, senior vice president for Research and Global Programs with March of Dimes, and professor emeritus of Pediatrics at Columbia University. "I worry about this article because it could be over-interpreted, and over-interpreting data of this nature is probably dangerous."
March of Dimes, a leading non-profit organization devoted to pregnancy and baby health, currently recommends that women abstain from alcohol while pregnant.
Dr. Richard Besser, ABC News Chief Health and Medical Editor, said, "I'd be very concerned if a woman saw this study and felt that it gave her a green light to drink during pregnancy."
Other doctors were somewhat less worried about how pregnant women would interpret the results.
"It does not justify heavy drinking," said Dr. Bruce Levin, professor and chair in the department of Biostatistics at Columbia University's Mailman School of Public Health in New York. "But it does alleviate concerns that light drinking causes huge problems."
"While many would rather counsel moms not to drink at all," said Dr. Ian Holzman, vice chair of Clinical Affairs and professor of Pediatrics at Mount Sinai Medical Center in New York, "It has always seemed a bit of a stretch to believe that minimal amounts of drinking would harm the fetus. I believe the bulk of the evidence is consistent with this study."
Thus far, the study, which includes data from more than 11,000 children born between September 2000 and January 2002, has found no significant differences in the behavioral and cognitive development of children whose mothers either abstained from alcohol or drank lightly while pregnant.
But the researchers so far have only looked at these kids until the age of five. The children in the study will continue to be monitored as they mature -- and even the researchers doing the work say pregnant women should not take their findings so far as an excuse to drink while pregnant.
"We are not taking on an advocacy role with this research," said Dr. Yvonne Kelly, lead author of the research and graduate tutor in the department of Epidemiology and Public Health at University College London. "These findings are consistent with those from our prior work. We will continue to assess the relationship as children get older."
In the study, women were placed into categories, including teetotalers who never drank alcohol; those who abstained while pregnant; light drinkers (one to two drinks per week); moderate drinkers (three to six per week, or three to five at any one time); and heavy drinkers (seven or more drinks per week or six in one sitting). Nine months after giving birth, the mothers were interviewed on their drinking patterns while pregnant, as well as social and economic factors.
While this research has not yet shown that light drinking during pregnancy is linked to developmental risks, it is widely known that heavy drinking during pregnancy can cause significant physical and behavioral problems in children, including fetal alcohol syndrome, birth defects, and low birth weights. According to the Centers for Disease Control and Prevention, binge drinking, defined as having five or more drinks on at least one occasion in 30 days, is particularly harmful to fetal brain development.
Mothers-to-be who drank heavily in the new study were more likely to have children who were hyperactive, with more behavioral and emotional problems than children whose mothers abstained.
"The link between heavy maternal alcohol use and risks to the fetus is well-established," said Dr. Rahil Briggs, director of Healthy Steps at Montefiore Medical Center. "We know less about those mothers-to-be who drink small amounts. In that way, [the study] is helpful."
But it does not change many doctors' minds.
"I don't think there will ever be a time that the American Congress of Obstetricians and Gynecologists or the American Academy of Pediatrics come out to say, 'Oh yes, you can consume small amounts of alcohol during your pregnancy," said Dr. Ari Brown, a pediatrician in private practice in Austin, Texas and co-author of the book "Baby 411." "As such, practicing clinicians won't either. The potential lifetime risks to the child simply aren't worth taking."