NEW YORK (Reuters Health) - Women who experienceasthma flare-ups during the first trimester of pregnancy are atincreased risk for having a baby with a birth defect, according toa report in the Journal of Allergy and Clinical Immunology.

A first-trimester flare-up increased the odds of a malformationby 48 percent, note Dr. Lucie Blais and Amelie Forget, fromUniversite de Montreal and Hopital du Sacre-Coeur de Montreal. Formajor malformations, the risk increased by 32 percent.

“This study adds evidence to the necessity of keeping asthmaunder control during pregnancy to avoid exacerbations,” theinvestigators write.