No safe drinking level in pregnancy, specialist asserts

No, no, and no, Dr. Timothy Naimi says.

Nobody recommends women drink alcohol while pregnant. There is no safe amount of alcohol a pregnant woman can drink, given ample evidence that alcohol kills brain cells in the developing fetus. And no one should change their thinking based on a British study that found no increased risk for social or cognitive problems among five-year-olds whose mothers had one or two drinks a week while pregnant.

“The results are highly implausible,” said Naimi, a Boston Medical Center physician and alcohol epidemiologist. “Alcohol is the leading fetal neurotoxin in the world. One would be challenged to come up with an explanation of why [the study results] would be biologically true.”

The British researchers report in the Journal of Epidemiology and Community Health on more than 11,500 children enrolled in a national study. Their mothers were asked about their drinking habits during pregnancy and the children's vocabulary and other cognitive abilities were tested at home by researchers. Children born to light drinkers scored better than children whose mothers stopped drinking during pregnancy. But there was something else about the light drinkers that was also important, the authors and Naimi said.

Light drinkers had family income that was twice as high as those who gave up alcohol while pregnant. They were more than twice as likely to be highly educated and almost twice as likely to work as a manager or professional as the non-drinkers during pregnancy. Teetotalers and heavy drinkers were not included in the comparison that the authors used. When the authors took the light drinkers' social circumstances into account, the differences between the children diminished.

“This study is hopelessly confounded by socioeconomic factors in that, as most people would be aware, people with high socioeconomic status generally have kids with much lower rates of behavioral and learning problems. And yet these are the same women who may consume very small amounts of alcohol in pregnancy,” Naimi said.