Diagnosis and successful treatment of fetal goitrous hyperthyroidism caused by maternal Graves disease

Intrauterine diagnosis and treatment of fetal goitrous hyperthyroidism due to maternal Graves disease has not been reported.

A case of fetal goitrous hyperthyroidism caused by maternal Graves disease was diagnosed and treated in the second trimester. High concentrations of both thyroid-stimulatory immunoglobulins (Igs) and thyrotropin-binding inhibitory Igs were detected in both maternal and fetal umbilical venous blood. Maternal propylthiouracil (PTU) treatment resulted in normalization of fetal thyroid function and a decrease in the size of the fetal thyroid goiter. Although euthyroid immediately after birth, the infant later became hyperthyroid and required treatment with PTU.

The relatively high frequency of fetal thyroid disorders in maternal Graves disease warrants complete maternal and fetal evaluation. Fetal diagnosis and treatment of either hyperthyroidism or hypothyroidism are feasible and necessary to prevent fetal morbidity and mortality.