Children born to mothers who smoke during pregnancy are 65 per cent more likely to develop asthma, new research has revealed.

The study, published online in the American Journal of Respiratory and Critical Care Medicine, looked at the case history of nearly 22,000 children, and found that those whose mothers smoked during the first three months of pregnancy were at the greatest risk of asthma or of developing a wheeze.

Dr Asa Neuman, of the Karolinka Institute, Stockholm, Sweden, said: "These results indicate the harmful effects of maternal smoking on the foetal respiratory system begin early in pregnancy, perhaps before the woman is even aware she is pregnant."

The scientists looked at eight birth cohorts from across Europe to reach the results. They found that in 39 per cent of cases, children were born with a wheeze when the mother smoked during pregnancy and 65 per cent of children developed asthma.

Dr Neuman said the results should serve a warning to young women who smoke, saying they should "be encouraged to quit before getting pregnant."

Posted by Robert Mair on 17/08/2012