PATTERN OF OESTRIOL CONJUGATES IN HUMAN CORD BLOOD, AMNIOTIC FLUID, AND URINE OF NEWBORNS

Abstract

Free and conjugated oestriol (oestra-1.3.5(10)-triene-3,16α,17β-triol) were measured in extracts of human cord blood, amniotic fluid and urine of newborns and the pattern of oestriol conjugates in these body fluids was determined. The bulk of oestriol occurred in a conjugated form, with more free oestriol (12 %) in cord blood than in amniotic fluid (2.5 %) or urine of newborns (1.5%). Sodium oestriol-3-sulphate has been identified in extracts of cord blood, amniotic fluid and urine of newborns. It is the principal oestriol conjugate of the cord blood (86% of total conjugated oestriol), but is only a minor component in the amniotic fluid (15 %) or in the urine of newborns (11%). Sodium oestriol-16(17?)-glucosiduronate has been identified in extracts of amniotic fluid and urine of newborns, and partially characterized in extracts of cord blood. It constitutes some 50% of the total conjugated oestriol of the amniotic fluid and urine of newborns, but amounts only to approximately 1 % of the total conjugated oestriol of cord blood. Three additional oestriol conjugates have been detected and partially characterized in the body fluids studied. Two of them appear to be dior tri-glucosiduronates. The quantitatively most important third one is a double conjugate: possibly oestriol-3-sulphate-16 and/or 17-glucosiduronate, or oestriol-3-sulpho-glucuronide. It is suggested that transconjugation of oestriol-3-sulphate into oestriol glucosiduronates takes place in the human foetus and newborn.