Intrauterine Diagnosis and Treatment of Fetal Goitrous Hypothyroidism

Abstract

Newborn screening programs for the detection of congenital hypothyroidism have dramatically shortened the time before treatment is begun. However, concern still exists about central nervous system sequelae which may persist due to a period of untreated intrauterine hypothyroidism. Presence of polyhydramnios led to the ultrasound diagnosis of a fetal goiter. Hypothyroidism was confirmed at 34 weeks gestation by percutaneous fetal blood sampling, which revealed an elevated TSH (186 mU/L) and a low T4 (19.3 nmol/L). Intraamniotic fluid injections of 500 micrograms levothyroxine sodium (T4) every 10-14 days increased fetal serum T4 (59.2 nmol/L), decreased fetal serum TSH (14 mU/L), decreased amniotic fluid TSH, and decreased the size of the fetal goiter. The infant was born at term without perinatal complications. Thyroid function studies on cord blood were normal (T4, 109.4 nmol/L; TSH, 1.3 mU/L), and the infant was discharged on oral T4. Follow-up examination at age 6 weeks revealed that the infant was developmentally normal and clinically and chemically euthyroid. Intrauterine T4 therapy can suppress fetal TSH and treat fetal hypothyroidism despite hypothyroid levels of serum T3. Highly sensitive TSH assays may allow the use of amniotic fluid TSH as a marker for fetal hypothyroidism.

Maternal compound W serial measurements for the management of fetal hypothyroidsm

“…However, this is an invasive procedure, associated with 1% fetal loss (12). However, this approach allows the early diagnosis of fetal hypothyroidism and the provision of substitutive therapy in utero (25,26). Several recent studies have shown that intrauterine hypothyroidism is associated with decreased IQ values at 3-7 years even if a correct neonatal thyroid hormone replacement therapy is provided (27)(28)(29)(30)(31)(32).…”

Antenatal diagnosis and treatment of a case of fetal goitrous hypothyroidism associated with high‐output cardiac failure

“…Moreover, a large goiter may cause malpresentation and may complicate labor. Perelman et al 3 reported that fetal goitrous hypothyroidism was successfully treated by intraamniotic injection of 500 µg levothyroxine sodium every 10-14 days. Davidson et al 4 has also stated that weekly injections of 250 µg of levothyroxine would closely approximate the thyroxine requirement of a newborn baby with hypothyroidism (10 µg/kg body weight/day).…”

“…Antenatal diagnosis of fetal goiter may be crucial for the immediate postnatal management of affected neonates. It has been reported that fetal goitrous hypothyroidism was diagnosed in utero based on sonography and on thyroid stimulating hormone (TSH) assays of umbilical blood samples and amniotic fluid, and was successfully treated by intra-amniotic injection of thyroid hormone, resulting in a decrease in fetal TSH level and a decrease in the size of the goiter [2][3][4][5] . Though the high vascularity of fetal goiter has been reported 6 the circulatory status of such fetuses has remained unknown.…”

Thyroid Disorders during Pregnancy: Impact on the Fetus

“…This explains why, even in congenital hypothyroidism with delayed bone maturation at diagnosis (indicating a prenatal onset), the intellectual outcome is typically normal if treatment is instituted shortly after birth [12,13]. Thus, in utero treatment of fetal hypothyroidism is usually only considered in rare circumstances, such as for goiters causing hydramnios or when vaginal delivery is likely to be impeded [14]. We have reported results from 12 cases that confirm the feasibility and safety of intrauterine L -thyroxine treatment of nonimmune fetal goitrous hypothyroidism.…”