[Transient neonatal hypothyrosis in premature neonates]

Plasma levels were measured of T4, free T4, T3, TSH in 64 premature neonates and in 41 those born at right time during the time-related course of the neonatal period. The results secured permit regarding the thyroid hypohormonosis syndrome in premature neonates as a consequence of the hypothalamic-hypophyseal-thyroid axis deficiency and of immaturity of the thyreostatic receptors as well. On the one hand, this promotes hypometabolism and, correspondingly, favours more economic utilization of bodily energy resources but on the other hand, such adaptation is not infrequently results in its failure and persistent thyrodeficiency, especially in very low-birth weight infants, during the whole of the neonatal period.