Assessment of fetal thyroid function by colored Doppler echography

The association of hyperthyroidism and pregnancy is a rare but serious condition which can jeopardize fetal outcome. Classical follow-up relies on: serial clinical and echographic assessment; serial funipuncture to determine fetal thyroid status, and maternal propylthiouracil (PTU) treatment to treat fetal and/or maternal hyperthyroidism.We report the case of a euthyroid patient with Graves' disease who had already been delivered of two hyperthyroid fetuses; the present pregnancy revealed a hyperthyroid fetus diagnosed by funipuncture. Echography showed a fetal goiter at 28 weeks of gestation (WG) with important signal on colored Doppler echography. We observed an extinction of this signal as maternal PTU treatment was intensified. The patient was delivered of a mildly hyperthyroid newborn at 37 WG. Both newborn and patient are doing well.Fetal thyroid assessment by colored Doppler echography could help in the management of fetal thyroid dysfunction.