Successful intra‐amniotic levothyroxine treatment for fetal goitrous hypothyroidism in a triplet pregnancy

We report an extremely challenging case of fetal goitrous hypothyroidism involving all three fetuses of a triplet pregnancy in which successful fetal treatment led to a favorable pregnancy outcome. The patient had a trichorionic, triamniotic triplet pregnancy and was referred to us at 24 weeks gestation after goiters affecting all three fetuses and polyhydramnios involving two fetuses were noted. Immediately before the conception, she underwent hysterosalpingography with an oil-soluble iodinated contrast medium. After the diagnosis of fetal hypothyroidism was made, intra-amniotic injection of levothyroxine was performed for two fetuses with polyhydramnios 3 times between 28 and 31 weeks gestation. The goiters shrunk and the polyhydramnios improved in response to the in utero treatment. No complications occurred. Cesarean section was performed at 33 weeks gestation. None of the three neonates developed respiratory insufficiency. Our experience suggested that successful intrauterine treatment is possible for fetal goitrous hypothyroidism, even in a triplet pregnancy. The indication, treatment timing, and diagnostic and assessment strategies should be carefully discussed to minimize puncture-related complications.