Does Subclinical Maternal Hypothyroidism in Early Pregnancy Affect Neurodevelopmental Outcomes in Children?

According to a small study from Japan, maternal thyroxine deficiency limited to early pregnancy does not affect neurodevelopment.

A fetus depends on maternal thyroxine until about 18 to 20 weeks' gestation, when the fetal thyroid starts to secrete its own thyroxine. Case-control studies have demonstrated an association between mild maternal thyroxine deficiency in early gestation and adverse neurodevelopmental outcomes in children (e.g., JW Womens Health Sep 1 1999). Investigators in Japan examined this association further because they had not observed the same adverse outcomes when maternal thyroid status was restored to normal by late pregnancy.

In five pregnant women (3 with histories of thyroid disease), hypothyroidism was detected at 6 to 16 weeks' gestation; all were treated with thyroxine. Four of the women achieved a euthyroid state by 20 weeks' gestation; one …

Reviewing Author

Martin T. Stein, MD

Disclosures

Consultant / Advisory boardPearson Neuroscience Advisory Board

Speaker’s bureauAmerican Academy of Pediatrics

RoyaltiesElsevier, Inc.

Editorial boardsJournal of Developmental and Behavioral Pediatrics