Antithyroid Drugs Tied to Risk for Congenital Malformations | oneGRAVESvoice

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Antithyroid Drugs Tied to Risk for Congenital Malformations


Infants born to women who received antithyroid drugs (ATDs) for Graves disease (GD) during the first trimester of pregnancy have an increased risk for congenital malformations, a study has found.

“ATD exposure during the first trimester was associated with significantly increased risk for congenital malformations, particularly for pregnancies in which women received prescriptions for MMI [methimazole] or both ATDs” (MMI or propylthiouracil [PTU]), the researchers write.

Gi Hyeon Seo, MD, from Health Insurance Review and Assessment Service, Wonju-si, Gangwon-do, Korea, and colleagues published their findings online today in Annals of Internal Medicine.   

The authors note, however, that the risk to the fetus must be balanced against the mothers’ risks. “Untreated or insufficiently treated GD may result in pregnancy loss and serious fetal and maternal sequelae, providing a compelling indication for timely administration of antithyroid drugs,” the researchers explain.

Antithyroid Drugs Tied To Risk For Congenital Malformations