Use of 3-dimensional sonography for prenatal evaluation and follow-up of fetal goitrous hypothyroidism

Intra-amniotic levothyroxine infusions in a case of fetal goiter due to novel Thyroglobulin gene variants

Indications and administration of intra-amniotic infusions of L-thyroxine in the context of non-immune fetal hypothyroidism with goiter lack of standardization. Systematic follow-up of clinical features related to thyroid hormonal homeostasis may be useful to evaluate their efficiency and develop standardized management guidelines.

Fetal goiter conservatively monitored during the prenatal period associated with maternal and neonatal euthyroid status

Congenital goiter is considered a rare occurrence, and may be related to hypothyroidism, hyperthyroidism, or euthyroidism. In this report, we describe a case of fetal goiter identified in the 34th gestational week in a 41-year-old secundigravida with normal thyroid functions. A conservative approach was followed; the fetal goiter was monitored via ultrasound, which suggested this was a case of hyperthyroidism. After the birth, tests indicated that the newborn was euthyroidic. Consequently, a more detailed study using non-invasive procedures was deemed necessary to discover the precise cause of the fetal goiter during the gestational period.

Intra-amniotic thyroxine to treat fetal goiter

A 35-year-old pregnant woman visited our department and had been treated with 100 µg of daily oral levothyroxine for hypothyroidism. An ultrasonography screening was performed at 25 weeks gestation and revealed a fetal goiter and an increased amniotic fluid volume. Fetal hypothyroidism was confirmed by cordocentesis and amniotic hormone levels at 26 weeks gestation. We treated the mother with 200 µg of daily oral levothyroxine to optimize the transplacental transfer. A total of four intra-amniotic injections of levothyroxine were administered, resulting in progressive reduction in the fetal thyroid volume of goiter as measured by 3D ultrasonography and increased amniotic fluid volume. Following birth, neonatal serum thyroid stimulating hormone level was within the normal range, but free T4 was reduced. Based on this case, we suggest that monitoring amniotic fluid thyroid hormone concentration and intra-amniotic levothyroxine injection can be used to reduce the thyroid volume of goiters and to prevent polyhydramnios.