FETAL THYROTOXICOSIS - A CASE-REPORT AND RECOMMENDATIONS FOR PREDICTION, DIAGNOSIS, AND TREATMENT

A maternal history of Graves' disease places the fetus at risk for thy rotoxicosis in utero via the placental transfer of thyroid-stimulating immunoglobulins. Methods for prediction of fetal hyperthyroidism are available, but are not widely used. Clinical assessment of fetal thyro id status by monitoring of fetal heart rate and growth may be inaccura te. This raises some uncertainty in the initial diagnosis of fetal thy rotoxicosis and complicates the assessment of fetal response to matern al propylthiouracil therapy. A case illustrating these pitfalls in the diagnosis and management of fetal hyperthyroidism is presented. The c ondition was correctly diagnosed, but treatment based on fetal heart r ate resulted in biochemical hypothyroidism in the infant at birth. Cur rent recommendations for diagnosis and treatment of fetal hyperthyroid ism are reviewed along with recent developments in the field. A modifi ed approach is proposed.