In pregnant women with past or current Graves' disease, ultrasonography of the fetal thyroid gland by an experienced ultrasonographer is an excellent diagnostic tool. This tool in conjunction with close teamwork among internists, endocrinologists, obstetricians, echographists, and pediatricians can ensure normal fetal thyroid function.

Objective: Hyperthyroidism in neonates born to mothers with Graves' disease (GD) can be associated with significant morbidity and mortality, but is still overlooked by clinicians. Management of neonatal hyperthyroidism would be improved by a better understanding of the predictive factors involved. The aim of this study was to evaluate the course of thyroid function and clinical outcomes during the first postnatal month in babies born to mothers with GD. Design: Prospective observational study. Methods: Sixty-eight neonates born to mothers with GD were managed from birth and divided into three groups based on thyrotropin receptor antibody (TRAb) and anti-thyroid drug (ATD) status in the mother: TRAb /ATDCve neonates, 24 (72.7%) had positive TRAb on cord blood assays, and seven of these developed neonatal hyperthyroidism. FT 4 elevation between days 3 and 7 but not at birth was predictive of the development of hyperthyroidism. Conclusions: TRAb status should be checked in the third trimester in mothers with GD and on cord blood in their neonates; if positive, it indicates a high risk of neonatal hyperthyroidism. FT 4 measurement at birth should be repeated between days 3 and 5 (and by day 7 at the latest); rapid FT 4 elevation during the first postnatal week is predictive of hyperthyroidism and warrants ATD therapy.