One or two glasses of wine a week enough to harm unborn child: study
November 16, 20123:50AM
Just two glasses of wine a week might be enough to harm an unborn child, new research suggests. Source: Supplied
JUST one or two glasses of wine a week during pregnancy are enough to lower a child's IQ, a new study suggests.
The research, led by researchers from Oxford and Bristol universities and published in the journal PLOS ONE, is one of the first of its kind to look at the effects of moderate drinking during pregnancy.
Lead researcher Dr Ron Gray, from the National Perinatal Epidemiology Unit at the University of Oxford, said it was a complex study but the message was simple.
"Even moderate amounts of alcohol during pregnancy can have an effect on future child intelligence," he said. "So women have good reason to choose to avoid alcohol when pregnant."
Current official guidelines vary around the world. In Australia, women are told that "for women who are pregnant or planning a pregnancy, not drinking is the safest option."
It is well established that heavy drinking can damage a child in utero.
However the guidelines also say that, based on the evidence in 2009 when the policy was updated, the risk is "likely to be low if a woman has consumed only small amounts of alcohol (such as one or two drinks per week) before she knew she was pregnant or during pregnancy."
Previous studies on the effects of moderate alcohol intake on a child's IQ have produced conflicting results, because it is difficult to separate it from other factors such as lifestyle, smoking, diet, affluence and education.
The new study tried to isolate alcohol as a factor by looking at genes linked to the metabolising of alcohol in 4000 mothers and their children.
If a mother had genes that made her clear alcohol more slowly from the bloodstream, she would expose her fetus to more alcohol.
And if the children had these slow-processing genes, and their mothers drank even in moderation during pregnancy, they scored 3.5 points lower on IQ tests, on average.
There were four genetic variations that affected how alcohol is metabolised, and each was linked to a two-point loss of IQ in the child.
The results mean that, in theory, some women may be able to drink a glass of wine occasionally without harming their babies.
However because they do not know the genetic makeup of themselves or their child, women should not take the risk, the researchers said.
"Even at levels of alcohol consumption which are normally considered to be harmless, we can detect differences in childhood IQ, which are dependent on the ability of the foetus to clear this alcohol," said Dr Sarah Lewis from the University of Bristol, the report's first author.
"This is evidence that even at these moderate levels, alcohol is influencing foetal brain development."
Dr Simon Newell, vice president for training and assessment at the Royal College of Paediatrics and Child Health, said: "It is impossible to say what constitutes as a 'safe' amount of alcohol a mother can drink as every pregnancy is different, so our advice to mothers is don't take a chance with your baby's health - drink no alcohol at all."
