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Antithyroid drugs and congenital malformations

Nature Reviews Endocrinologyvolume 14pages328329 (2018) | Download Citation

A new study showed that propylthiouracil and methimazole use during pregnancy was associated with increased risk of congenital malformations. Intriguingly, the authors identified dose-dependent effects for methimazole but not propylthiouracil, whereas the recommended switch from methimazole to propylthiouracil during early pregnancy did not reduce the risk of congenital malformations.

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  1. Academic Center for Thyroid Diseases, Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, Netherlands

    • Tim I. M. Korevaar
    •  & Robin P. Peeters


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The authors declare no competing interests.

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Correspondence to Tim I. M. Korevaar.

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