Women considered obese before becoming pregnant are four times more likely to have infants with frequent wheezing during the first 14 months of life, compared to those born to normal-weight mothers, according to researchers from the Centre for Research in Environmental Epidemiology (CREAL) in Barcelona, Spain.

Investigators made the discovery after analyzing data from 1,107 pairs of mother and child. While the impact on frequent wheezing is significant, researchers discovered that maternal obesity did not increase the risk of the child to have any or infrequent wheezing.

The authors believe the research adds more evidence to the effects of fetal exposure and its consequences on asthma-related phenotypes.

“It is plausible that maternal obesity may be associated differentially with specific wheezing subphenotypes during infancy and that it may influence the risk of frequent wheezing, which is related to subsequent asthma susceptibility,” the authors wrote. “This later association may be stronger than the risk of infrequent wheezing episodes, which are mainly related to episodes of viral infections and often have no apparent asthma-related sequelae later in life.”