Plasma Cortisone and Cortisol Levels at Birth and During the Neonatal Period

Abstract

Cortisol and cortisone were measured in maternal and cord plasma, as well as in newborn plasma, by a double isotope dilution derivative assay. An assessment of the reproducibility, precision and sensitivity of the method is presented. It was found that cortisone concentration in cord plasma is greater than in maternal plasma, that following birth the plasma level of cortisone is maintained during at least the first week of life, and that both cortisol and cortisone concentration increased following the administration of ACTH.