[Pituitary-adrenal cortical function in newborn infants--especially in the ratio of unbound unconjugated corticosteroids (author's transl)].

It has already generally been accepted that there are a variety of fetal adaptations to a stress during delivery and the fetal endocrinological functioning is being controlled mainly by the pituitary adrenal axis. An endocrinological difference between fetuses given a stress and the controls was observed in this study. The levels of ACTH and cds in the umbilical cord blood are supposed to be the indicators of stresses. The measurements of not only those levels but the percentile value of non-protein bound cds (NPC), known for an active form, were conducted under various conditions. Consequently, the three following results were obtained. 1. In the group of infants delivered by the vacuum extraction, the levels of ACTH and percent free cds tended to be more increased, and those of total cds and NPC were significantly higher than both groups of infants delivered spontaneously and by the oxytocin induction. 2. There were no significant differences in the levels of ACTH, total cds, percent free cds and NPC in plasma between the groups of mothers when delivered spontaneously and by the vacuum extraction. 3. The levels of ACTH, total cds, percent free cds and NPC in umbilical cord blood in infants with asphyxia were significantly higher than the normal.