Women who are overweight or obese when they become pregnant might be more likely to have children who develop asthma as teenagers, new research shows.
The findings, published in The Journal of Epidemiology & Community Health, could point to yet another consequence of the rising rates of obesity worldwide. Scientists have documented a number of complications that are more likely to arise in women who are obese before they become pregnant, among them a greater risk of preterm deliveries.
The prevalence of asthma has risen substantially across the globe since the 1970s. In the latest study, researchers from England and Finland sought to explore whether the obesity trend might have played a role, focusing on about 7,000 teenagers who were born in northern Finland.
The researchers questioned the mothers of the children about their lifestyles and backgrounds. They also collected detailed health histories of both parents, including medical records from before conception.
The researchers found that the teenagers whose mothers had been overweight or obese just before they became pregnant were 20 percent to 30 percent more likely to have asthma or a history of wheezing. And the teenagers whose mothers had the highest pre-pregnancy weight were nearly 50 percent more likely to have had a history of severe wheezing.
Previous research has shown that excess weight during pregnancy might increase levels of leptin, a hormone that binds to receptors in the fetal lung.