Intrauterine diagnosis and management of fetal goitrous hypothyroidism: a report of an Iranian family with three consecutive pregnancies complicated by fetal goiter.

The diagnosis and treatment of hypothyroidism during the fetal period may decrease perinatal morbidity and are believed to be important to optimize growth and intellectual development. Herewith a case report of fetal goitrous hypothyroidism is presented in a euthyroid mother, detected at 34 weeks' gestation by ultrasonography, and treated with intra-amniotic levothyroxine injections. The mother had two previous consecutive pregnancies (13 and 8 years ago), also complicated by the occurrence of fetal goiter, resulting in tracheal compression, asphyxia, and early neonatal death in the first and in an emergency cesarean section delivery, because of fetal malpresentation, in the second neonate affected by congenital hypothyroidism (CH). The present male newborn, although born without observable goiter, had a large thyroid on ultrasonography and an early rise of his peripheral venous blood thyrotropin confirmed the diagnosis of CH. Low serum thyroglobulin in the proband and his older brother and parental consanguinity was mostly compatible with a thyroglobulin defective synthesis and secretion as the cause of CH and fetal goiter. Despite apparently sufficient dose of intraamniotic levothyroxine injections repeated weekly from 34-37 weeks' gestation (i.e., four injections of 500 microg levothyroxine), neonatal bone age on the second day of life showed delayed skeletal maturation.