Ulrik Schioler Kesmodel and Erik Lykke Mortensen of Aarhus University said the study involved 1,628 Danish children registered in the Danish National Birth Cohort Better Health for Mother and Child, which includes information on mothers' alcohol habits during pregnancy.
The study, published BJOG, an obstetrics and gynecology journal, found children born to mothers who consumed between one and six alcohol units per week were as intelligent and well-developed as children of mothers who abstained from alcohol.
Mothers who had been drinking five or more drinks on a single occasion a limited number of times before realizing they were pregnant might breathe a sigh of relief -- their children were not harmed, the study said.
"The Danish Health and Medicines Authority recommends pregnant women to abstain completely from alcohol consumption, but we know from other studies that about half of the pregnant women do not entirely stay away from alcohol during pregnancy," Kesmodel said in a statement. "Many of these mothers report binge episodes during the period before they even knew that they were pregnant. Now we have scientific evidence which may set their minds at ease."