MATERNAL PLASMA TOTAL ESTRIOL AND DEHYDROEPIANDROSTERONE SULFATE LOADING TEST AS INDICATORS OF FETOPLACENTAL FUNCTION OR PLACENTAL SULFATASE DEFICIENCY

Serum total oestriol (E3P) concentrations were measured by radioimmunoassay with I125 oestriol after enzymatic hydrolysis, and the range of values were first established in 88 normal singleton pregnancies. E3P and urinary oestrogen excretion were estimated in 141 high-risk subjects throughout the last trimester of pregnancy and free oestriol determinations were also made in some cases of diabetes on intra-uterine growth retardation (IUGR). The intra-uterine fetal deaths were easily predictable from E3P, even in seven cases of toxemia and one of diabetes. The lack of increase of E3P during the 4 weeks preceding delivery indicates severe fetal hypotrophy and/or malformation. Total- and free-E3P and urinary oestrogen excretion were studied in 222 pregnancies with IUGR and their predictive efficacity were compared. The half-life of dehydroepiandrosterone sulfate (DHA-S) and the increase of unconjugated oestradiol (E2) after IV of the former have been determined in both pregnancies, normal and with retarded fetal development. The E2 increases and chiefly the lengthening of DHA-S half-life provide accurate assessment of the utero-placental function and fetal well-being, and obviously allow the diagnosis of placental sulfatase deficiency. The conclusion of this study is that the assessment of high-risk pregnancies, until now accomplished principally by urinary oestriol assays, may be performed by more convenient and rapid radioimmunoassays of plasma oestriol, and completed in some cases (IUGR, placental sulfatase deficiency) by dynamic tests, chiefly by DHA-S half-life determinations. © 1979.