ECE2006 Symposia Endocrinology in the foetus (4 abstracts)
Paediatric Endocrinology, Charité, University Medicine Berlin, Germany.
Endocrine fetal therapies is currently performed in congenital adrenal hyperplasia due to 21-hydroxylase and 11 beta-hydroxylase deficiencies (CAH), hypothyroidism accompanied by large goiter and in thyrotoxicosis due to maternal autoantibodies. In CAH dexamethasone is administered to the mother 56 weeks p.c. to suppress the fetal hypothalamo-pituitary-adrenal axis. If the diagnosis is confirmed by chorionic villus or amniocentesis therapy is continued, while it is discontinued in all males as well as in unaffected females. Studies of patients with prenatally treated CAH following strict protocols in North America and Europe did not observe shortterm adverse effects in the fetus and provided evidence that virilization of female external genitalia can be prevented or reduced thereby reducing the necessity of genitoplasty. However, animal studies and epidemiological data have shown various adverse effects of glucocorticoids on the developing fetus and it is not known whether glucocorticoids induce fetal programming of metabolic changes that manifest as disease in adult life. Therefore according to international consensus guidelines this treatment should be considered as experimental and only be performed in controlled studies. Intra amniotic administration of thyroid hormone has successfully been used in reducing goiter size in fetuses of mothers with antithyroid drug treatment and in fetuses with congenital hypothyroidism. It is still a matter of controversy if prenatal thyroid hormone treatment is necessary in other patients with congenital hypothyroidism. However the normal outcome in the majority of the cases detected by newborn screening indicates that an early and adequate postnatal therapy seems to be sufficient. There are no reports on prospective treatment studies in fetuses of mothers with autoimmune hyperthyroidism. However, there is increasing evidence, that children of mothers with Graves disease may present with endocrine problems (fetal thyrotoxicosis, fetal and neonatal thyroidal or central hypothyroidism) and that the diagnosis is frequently missed. Therefore prospective, controlled studies as in the prenatal treatment of CAH are required.