THE EXCRETION OF NEUTRAL STEROIDS IN THE URINE OF NEWBORN INFANTS

Abstract

SUMMARY Following enzyme hydrolysis of the urine of infants aged 1 to 6 days, the neutral steroids have been extracted and their excretion patterns determined using a method based on paper chromatography. Three groups of compounds have been estimated—those reacting with Zimmermann reagent, those reducing blue tetrazolium and those giving sodium fluorescence. The first group includes the 17-oxosteroids and the latter two the corticoids. The steroid excretion patterns in the urine of these infants have been compared with those demonstrated by the same technique in adult female urine and in the urine of mothers in the 24 hr. following delivery. For all groups of compounds, the excretion patterns in the urine of infants are different from those found in the urine of their mothers or in that of adult women. The outstanding feature in infant urine is the dominance of compounds which behave like steroids, and which either do not occur in adult urine, or are present in insignificant amounts. Less obvious changes in the excretion patterns of 17-oxosteroids and of corticoids in pregnancy urine are also described. Many of the Zimmermann chromogens which are dominant in the urine in the first days of life have greatly diminished, or have disappeared, by the 6th day. This applies both to full-term and premature infants. The pattern of excretion of blue tetrazolium-reducing material in the urine of newborn infants is extremely complicated and, apparently, unique. Tetrahydrocortisol and tetrahydrocortisone, which are the major corticoid metabolites in adult urine, are much less prominent in the urine in the first 3 days of life. A blue tetrazolium-reducing steroid isolated from the urine of infants has been provisionally identified as 3β, 21-dihydroxypregn-5-ene-20-one. The altered steroid excretion patterns found in the urine of newborn infants are thought to indicate that there are fundamental differences in the metabolism of adrenal and placental steroids which are peculiar to this period and comparable with those established within recent years for oestrogens and progesterone.