Abstract: | The aim of this study was to evaluate thyroid gland function in neonates and babies with transient hyperthyrotrophinemia during the first twelve months of life in an attempt to establish the causes of this condition in neonates born in a region of slight iodine deficiency. Thirty-eight newborns were screened. Clinical observations and measurements of serum T3, T4, TSH levels as well as urinary iodine were conducted for one year (at the age of 2 weeks, 3-4 months, and after one year of life). The screened children showed significantly higher values of T4 (p < 0.001) in comparison with the reference value in successive follow-up examinations. High T4 values may result from an increased TBG concentration in serum, and its level should be determined in the analysed material. Other hormonal values normalized after the second weak of life. Iodine deficiency was found in 80% of the children. Our assessments concerning the causes of transient hyperthyrotrophinemia conform with previous findings. It was established that the most common causes are iodine deficiency and maternal thyroid disease. None of the screened children had goitre somatic anomalies or delayed psychomotoric development did not appear more frequently than in the general pediatric population. |