Article Text

Download PDFPDF
Thyroid status in the newborn infant
  1. T. G. Brien,
  2. J. A. Fay,
  3. E. A. Griffin

    Effective thyroxine ratio and free thyroxine index


    The effective thyroxine ratio (ETR) was determined in 28 term and 17 premature infants at birth and in 17 infants aged 0 to 6 weeks. The mean values found were significantly higher than those in 20 adult euthyroid controls. Serum thyroxine (T4), T3 resin uptake ratio (T3 RUR), free thyroxine index (FTI), and ETR were determined in 14 term infants at birth. It was concluded that the raised T4 was partly due to an increase in thyroxine binding globulin but that there was also a degree of true thyroid hyperactivity. Serum thyroxine alone was not considered a suitable index of thyroid function in infants and the free thyroxine index or the effective thyroxine ratio was preferred instead.

    Statistics from

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.