The fetus and the newborn are more sensitive than adults to a reduced environmental
iodine supply, and in
iodine-deficient areas, transient neonatal
hypothyroidism is frequently observed. This transient thyroid failure may be associated with neonatal
goiter and elevated serum
thyroglobulin levels at birth. Borderline elevated neonatal serum TSH concentrations frequently occur in newborns in
iodine deficient areas, and result in a higher recalling rate at the screening for
congenital hypothyroidism. Minor defects in mental performances and neurological development are observed in children living in areas of mild to moderate
iodine deficiency, and result from the concomitant effects of
iodine deficiency in the mother during pregnancy and transient neonatal
hypothyroidism.
Endemic cretinism is the severe and irreversible neurological consequence of
iodine deficiency during fetal and neonatal life.
Iodine prophylaxis is highly effective in preventing the development of
iodine deficiency disorders including transient neonatal
hypothyroidism. Since
iodine prophylaxis in Italy is inadequate, variable degrees of
iodine deficiency are still present all-over the country, and are responsible of a higher incidence of transient neonatal
hypothyroidism or hyperthyrotropinemia.