Drinking when pregnant ‘harms IQ’

A new study has found that drinking even small amounts of alcohol during pregnancy can reduce a child’s intelligence.

The study of over 4,000 mothers was published by the Public Library of Science One and was carried out by academics at Bristol and Oxford universities.

According to the research children of women who drank just two glasses of wine a week during pregnancy had lower IQs. Tests showed that at aged eight the children of mothers who had consumed between one and six units of alcohol a week were 1.8 IQ points less intelligent than children whose mothers had abstained.

The report concluded: “Associations between child’s genotype and outcome were only present among those whose mothers reported drinking alcohol in moderation during pregnancy.

“This suggests that, even amongst women drinking moderate amounts of alcohol, subtle changes in exposure to alcohol due to an ability to metabolise the substrate may be important, and offers some support to the hypothesis that even small amounts of alcohol in utero have an effect on future cognitive outcomes.”

At present the government’s advice is that pregnant women, and women planning a pregnancy, should avoid drinking alcohol in the first three months of pregnancy. The National Institute for Health and Clinical Excellence (Nice) further advises that, “if women choose to drink alcohol during pregnancy they should be advised to drink no more than one to two UK units once or twice a week”.

Nice continues: “Although there is uncertainty regarding a safe level of alcohol consumption in pregnancy, at this low level there is no evidence of harm to the unborn baby.

“Women should be informed that getting drunk or binge drinking during pregnancy (defined as more than five standard drinks or 7.5 UK units on a single occasion) may be harmful to the unborn baby.”

The NHS’s website advises women that, “during pregnancy, alcohol can pass freely from the placenta to the unborn baby and it is known that excess alcohol can harm the foetus. There is general agreement that women should not drink excessively during pregnancy. However, it is difficult to investigate the effects of alcohol on unborn children and it is therefore not clear what level of drinking is harmful to a pregnant woman and her baby.”

Ron Gray, co-author of the study, said: “This is a complex study but the message is simple: even moderate amounts of alcohol during pregnancy can have an effect on future child intelligence. So women have good reason to choose to avoid alcohol when pregnant,”

However Dorothy Bishop, professor of neuropsychology at the University of Oxford, told The Independent: “Unfortunately the researchers have lumped together mothers who reported drinking less than one unit [a small glass of wine] a week with those who drank as much as six units [a bottle of wine] a week. This makes it impossible to determine from these data if there is a safe level of drinking in pregnancy.”