PRENATAL TREATMENT OF FETAL HYPOTHYROIDISM - IS THERE MORE THAN ONE OPTION

Following the diagnosis of fetal goitre at 22 and 24 weeks' gestation in two hyperthyroid pregnant women who underwent treatment with 400-50 0 mg of propylthiouracil in the first weeks of pregnancy, a total of s even fetal blood samplings were performed to evaluate thyroid function before and after the initiation of two different treatment regimens. L-Thyroxine (600 mu g) was injected five times intra-amniotically in o ne woman and continuous maternal administration of the thyroid analogu e 3,5,3'-triiodothyroacetic acid (Triac) was attempted in the other. N ormalization of fetal thyroid function and reduction of fetal goitre w ere achieved in both fetuses and transplacental passage of Triac was i ndirectly demonstrated by high levels of free triiodothyronine in feta l blood. In cases of fetal hypothyroidism, direct or indirect prenatal therapy can be adopted successfully and safely.