Women who are already obese when they become pregnant are significantly more likely to have a child that suffers from frequent wheezing, a new study has shown.

Wheezing is a high-pitched whistling sound that is made while breathing. It is due to narrowed airways and the most common cause of recurrent wheezing is asthma.

According to Spanish researchers, it is already well established that obesity during pregnancy can have detrimental effects both on the mother and baby. They decided to look at the issue of wheezing more closely.

They looked at over 1,000 pairs of mothers and children and found that during the first 14 months of life, the risk of wheezing was four times greater among the children of obese mothers compared to the children of normal weight mothers.

The results stood even when other factors were taken into account, such as the birth weight of the child and whether the mother smoked.

"The independent relationship of obesity before pregnancy with the increased risk of frequent wheezing in children adds more evidence to the effects of foetal exposure and its consequences on asthma-related phenotypes (traits)," the researchers said.

They suggested that losing weight may lead to ‘possible preventative benefits'.

Details of these findings are published in the journal, Paediatric and Perinatal Epidemiology.

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