For decades, women have been told that drinking any amount of alcohol during pregnancy can harm their developing child. The zero-alcohol rule is so ingrained that just walking into a bar while pregnant can draw suspicious stares.

But new data from Denmark suggest that light to moderate drinking early in pregnancy — up to eight drinks a week — has no effect on intelligence, attention or self-control in children at age 5. Drinking more heavily, however, was associated with measurable negative effects.

Researchers studied more than 1,600 Danish women and their children. In five papers published in the BJOG journal, the authors report finding no effect of light, moderate or even binge drinking in pregnancy on children's overall IQ, ability to pay attention or executive function, which involves self-control and the ability to organize and plan behavior, at age 5.However, children of heavy-drinking women who had nine or more drinks a week had reduced attention span and were nearly five times more likely to have low IQ than children of nondrinkers.

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