Antenatal detection of placental steroid sulphatase deficiency by measurement of urinary 16α-hydroxydehydroepiandrosterone sulphate

Abstract

A simple gas chromatographic technique for the measurement of 16α-hydroxydehydroepiandrosterone sulphate in urine from pregnant women is described. An assessment was made of the effectiveness of the measurement of this oestriol precursor for the antenatal diagnosis of placental steroid sulphatase deficiency. Twenty-two patients whose pregnancies were complicated by subnormal oestrogen excretion for gestation were studied. In nine of these, where placental steroid sulphatase activity was found subsequently in vitro to be normal, the excretion of 16α-hydroxydehydroepiandrosterone sulphate was < 27 μmol/24 h. In the remaining 13 patients, in whom postnatal ih vitro assay demonstrated absence of placental steroid sulphatase activity, urinary excretion of 16α-hydroxydehydroepiandrosterone sulphate was 59-360 μmol/24 h. The excretion of this metabolite was below the limit of detection (20 μmol/24 h) in 30 uncomplicated pregnancies. It is concluded that urinary excretion of 16α-hydroxydehydroepiandrosterone sulphate > 50 μmol/day or a ratio of urinary 16α-hydroxydehydroepiandrosterone sulphate to urinary oestrogen > 2.0 correctly identifies, before delivery, those pregnancies in which fetus and deficient in steroid sulphatase activity.