Abstract
TSH and T4 were estimated prior to, and 30 & 180 min. after i.v. injection of 40 μg TRH in 15 fullterm (FT), 10 preterm (PT) and 15 small-for-gestational age (SGA) euthyroid babies, 5–172 hours after delivery. For comparison, 13 normal children, 8–382 days of age, and two hypothyroid patients, 3 and 28 days old, were studied. Results: 1) Basal levels of TSH and T4 were significantly lower in PT than in FT and SGA. 2) The decrease in TSH during the first 7 days of life was approximately exponential only in FT and SGA. 3) TSH (30 min.) was positively correlated to basal levels; the % increase in TSH was of same magnitude in all euthyroids. 4) TSH (180 min) remained elevated only in PT (2 α < 0.01) and in SGA (2α <0,05). 5) T4 (180 min) was significantly higher than basal values in all euthyroids, especially in PT. TSH was extremely high in both hypothyroid patients with no increase after TRH. The different responses in euthyroid newborn may be related to varying degrees of hypothalamic-hypopituitary maturation.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Jacobsen, B., Andersen, H., Dige-Petersen, H. et al. SERUM-TSH AND -T4 BEFORE AND AFTER TRH STIMULATION IN NEWBORN. Pediatr Res 9, 667 (1975). https://doi.org/10.1203/00006450-197508000-00017
Issue Date:
DOI: https://doi.org/10.1203/00006450-197508000-00017