Now, a new study adds fuel to the debate, finding that expectant mothers who drink moderately have children with better mental health than children of mothers who abstain. But even the author of the paper says her findings don’t mean moms-to-be should start imbibing.
“I really think we should recommend abstaining [from drinking] during pregnancy,” says study co-author Janni Niclasen, a post-doctoral student at the University of Copenhagen. “I really believe that even a glass of wine now and again is really damaging.”
In the U.S., doctors caution that any amount of alcohol could endanger the baby, while in many other countries moderate drinking during pregnancy is considered OK. Many moms remain passionately divided on the issue.
Studies have shown that heavy drinking causes birth defects. Niclasen was curious about how maternal drinking affected the mental health of their offspring.
“We know that drinking heavily is really, really bad for the fetus, but we are not so certain whether or not drinking a glass of wine is OK,” she says.
Niclasen looked at data from the Danish National Birth Cohort, which surveyed 37,000 women between 1996 to 2002. The women answered questions three different times and when their children were 7 years old, the kids took a questionnaire that assessed their emotions and relationships.
What Niclasen found surprised her: Children with mothers who drank moderately — about 90 units throughout pregnancy, which works out to about two drinks a week — experienced better mental health than children whose mothers completely abstained from drinking.
“The abstainers did the poorest in all outcomes. They were the poorest educated, smoked the most, did not exercise, and watched a lot of TV,” she says.
The moms who drank moderately did everything else right, in general; they exercised regularly, ate better, did not watch a lot of TV, had healthy BMIs, and were better educated. While these lifestyle factors have a huge impact on mental health, Niclasen found that when she controlled for them, mom’s alcohol consumption still had small influence on the children’s mental health.
Dr. David Streitman, an associate professor of maternal fetal medicine at Magee Womens Hospital of UPMC in Pittsburgh, said this study shows a correlation, not causation, between moderate alcohol consumption and a child’s mental health. Streitman, who was not involved in the study, said to be wary when interpreting the results.
“There is so much that happens to these kids between birth and 7 years of age … there is a lot of stuff you are not accounting for,” he said. Things like reading to a child or taking a lot of walks together could account for the small differences in mental health.
Even if the results don’t give us clear-cut answers, studies like these do add to a better understanding, Streitman said. “Really these types of papers help us generate new ideas … sometimes these lead to fantastic discoveries.”
Niclasen says one of the drawbacks of maternal alcohol studies is that the moms self-report their drinking habits and often underestimate or overestimate.
People have tried to quantify the amount of drinking a pregnant woman could do before risking her unborn baby’s health, but “it’s a rough estimate at best,” Streitman says. “There could be a ‘safe number’ [of drinks]. But we don’t know what that is.”
So for now, experts continue to recommend none.