Administration of Thyroxine to Very Low-Birth-Weight, Premature Infants

Abstract

To the Editor.— We question the advisability of administering thyroxine to premature infants with low thyroxine (T4) levels as reported by Chowdhry et al.1 The low T4 levels noted in this report would be expected in infants of 26 to 28 weeks of gestation. The serum thyrotropin (TSH) values were normal as was the response to thyrotropin-releasing hormone. Hadeed et al2 noted a prevalence of T4 levels less than 6.5 µg/dL in 52% of infants of 28 to 30 weeks of gestational age, 33% of infants of 31 to 33 weeks of gestational age, and 11% of infants of 34 to 36 weeks of gestational age.2