Drinking one or two glasses of wine a week during pregnancy1 can have an impact on a child's IQ, a study says.
一项研究显示,怀孕期间每周喝一两杯葡萄酒将影响孩子的智商。
Researchers from
Oxford2 and Bristol universities looked at the IQ scores of 4,000 children as well as
recording3 the alcohol
intake4 of their mothers.
They found "moderate" alcohol intake of one to six units a week during pregnancy
affected5 IQ.
Experts said the effect was small, but reinforced the need to avoid alcohol in pregnancy.
Previous studies have produced inconsistent and confusing evidence on whether low to moderate levels of alcohol are harmful in pregnancy, largely because it is difficult to separate out other factors that may have an effect such as the mother's age and education.
But this research, published in the PLOS One journal, ruled that out by looking at changes in the
genes6 that are not connected to social or lifestyle effects.
'Why take the risk?'
The study found that four
genetic7 variants8 in alcohol-metabolising genes in children and their mothers were strongly related to lower IQ at age eight.
But this effect was only seen among the children of women who drank between one and six drinks a week during pregnancy and not among women who
abstained11 when they were pregnant.
The researchers said although a causal effect could not be proven, the way they had done the study strongly suggested that it was exposure to alcohol in the womb that was responsible for the differences in child IQ.
Dr Ron Gray, from Oxford University, who led the research added that although the differences appeared small, they may well be significant and that lower IQ had been shown to be associated with being socially disadvantaged, having poorer health and even dying younger.
"It is for individual women to decide whether or not to drink during pregnancy, we just want to provide the evidence.
"But I would recommend avoiding alcohol. Why take the risk?"
A Department of Health spokesman said that since 2007 their advice had been that women who are trying to conceive or are pregnant should avoid alcohol.
But Dr Clare Tower,
consultant12 in obstetrics and fetal
maternal13 medicine, at St Mary's Hospital, Manchester, stressed that women who have had the occasional
alcoholic14 drink in pregnancy should not be overly alarmed by the findings.
"Current UK advice is that the safest course of action is abstinence during pregnancy.
But she
pointed17 out that another recent study had found no effect on IQ at five years.