If you haven’t heard about the recent study on “light drinking” during pregnancy, let me begin by saying that the data does not show that it is safe for pregnant women to drink.

While it is unlikely that an occasional drink will harm most unborn babies, there are some, for reasons we don’t fully understand, who may be affected by even small amounts of alcohol. So, if you are pregnant or are thinking of getting pregnant please follow the current recommendation and Just Say No to drinking while pregnant.

As for the recent findings and why they are generating so much controversy, read on.

The data source for the study in question was the UK (United Kingdom) Millennium Cohort study—a nationally representative longitudinal study. Trained interviewers conducted home visits when babies were 9 months and 3 years of age. During the first visit, mothers were asked about their drinking patterns during pregnancy, other health related behaviors, socioeconomic conditions and household composition. During the second visit, children (now 3 years of age) were assessed for behavioral and cognitive ability using the Strengths and Difficulties Questionnaire, British Ability Scale, and Bracken School Readiness Assessment.

Nearly 10,000 mother/baby pairs participated in the study. The findings, published in the International Journal of Epidemiology showed that there was no increased risk of behavioral or cognitive deficits at age 3, in children whose mothers consumed no more than 1-2 drinks per week or per occasion (at one time) during pregnancy, compared to children whose mothers abstained.

When boys and girls were evaluated separately, the study found that boys born to light drinkers were 40 percent less likely to have behavior problems and 30 percent less likely to be hyperactive, compared to boys born to mothers who had abstained. They were also more likely to score higher on vocabulary tests and were better able to identify colors and shapes.

Similarly, girls born to light drinkers were 30 percent less likely to have emotional symptoms and peer problems compared with girls born to mothers who had abstained.

If you are an expectant mother, you might be inclined to think twice about abstaining, under the pretext that 1 or 2 drinks each week will make your son better behaved or expand your daughter’s social circle.

But before you pop that cork or pop top, consider the following:

• This is only one study.

• Levels of drinking were self-reported, presumably some mothers may have reported not drinking during pregnancy, when in fact they did.

• This is an observational study which cannot determine causation. The fact that children of mothers who drank small amounts of alcohol during pregnancy scored higher on certain tests, doesn’t mean alcohol caused the improved performance.

• Behavioral problems or cognitive deficits may be obvious at older ages.

Yvonne Kelly, lead author, in an interview with Medical News Today suggested that light drinkers may be more social than non-drinkers, or that light drinkers may be more relaxed and this might cause better cognitive and behavioral outcomes in their children. She further emphasized the need for more research.

Women who have had a drink or two before they realized they were pregnant will find the results reassuring. But many health care providers worry that mothers will use the findings to justify drinking while pregnant. Given what is known about the effects of alcohol on the fetal brain, pregnant mothers should think twice before they belly up to the bar to imbibe.