Steroid spectrum in human urine as revealed by gas chromatography. VI. Pregnanediol excretion values and 3 beta-hydroxy-delta 5-steroid dehydrogenase activity of girls at different stage of development.

Pregnanediol excretion in the urine of girls aged 2-14 years was found to be 0.13 +/- 0.17 mg/day. Before puberty the amount of pregnanediol excreted was low but a marked increase could be observed during puberty. In the case of premenarchal girls this increase correlated well with increasing body weight, while in the presence of cycle ovarian function (anovulational cycles) it exceeded the expected level. The activity of 3 beta-hydroxy-delta 5-steroid dehydrogenase was assayed in vivo indirectly, by measuring pregnanediol (pregnanediol and androsterone + ethiocholanone) DHA ratios from urine. A composition of the two ratios indicated that the utilization of the endogenous C21 intermediate was one order of magnitude less than that of the C19 intermediate. To interprete this finding it is assumed that the delta 5-3 beta-HSD of the liver is on allotype of the adrenal enzyme with a reduced activity, towards the C21 intermediate. The biological significance of this presumption is also discussed.