Use of insect repellent associated with birth defect

Pregnant women should reconsider applying insect repellent after a study finds a link to an increasingly common birth defect. European researchers have found an association between mothers who used insect repellent in the earliest phase of pregnancy and an increased rate of malformed penises of their male children.

The association was identified in comparing nearly 1,000 babies (471 babies with “hypospadias,” [a misplaced opening on the penis] and 490 acting as a comparison group), and what their mothers wrote on surveys about their repellent use during their pregnancies.

“We found a significant association for risk of hypospadias with the use of insect repellents and total biocide score, but not with the use of individual biocides or indicators for its use,” Mark J. Nieuwenhuijsen, MD, of the Center for Research in Environmental Epidemiology at Parc de Recerca Biomedica de Barcelona, and colleagues wrote.

“Further work should be conducted on the possible reproductive effects of insect repellents, with consideration of the type, content, and mechanisms of action of specific formulations, and the current findings need to be replicated before firm conclusions can be drawn.”

Full story: Beyond Pesticides