Intrauterine exposure to the beta-adrenergic receptor-blocking agent metoprolol and allergy

Abstract

Cord blood IgE levels and the development of allergy were studied in 29 children born by mothers who had been treated with the beta-adrenergic receptor blocking agent, metoprolol, during the pregnancy and in 23 children of placebo-treated mothers. In 13 (45%) of the former and 3 (15%) of the placebo group elevated cord blood IgE levels, i.e. more than 0.9 kU/l and/or obvious or probable allergy developed (p = 0.03). The findings support previous experimental observations that beta-blocking agents may enhance IgE antibody formation. It also adds to the number of environmental factors that may increase the risk for atopic disease in children.