PLASMA UNCONJUGATED 15α‐HYDROXYOESTRIOL (OESTETROL) LEVELS IN NORMAL HUMAN PREGNANCY

Abstract

Serial measurements were made of the concentration of plasma unconjugated oestetrol in normal human pregnancy. The mean curve and limits of normal variation have been established. Plasma levels rose from just below 2 ng/ml at 20 weeks to approximately 5 ng/ml at term.

Variations in some of the body fluid hormone levels currently used for endocrine monitoring during the third trimester of pregnancy

“…The steroid hormones we have considered, differently from polipeptidic hormones, derive from different metabolic sources, even if both can give us useful indications about the well-being of the fetus-placental unity. In fact, we know that E 3 is sinthesized in the placenta from fetal precursors [21], while E 4 is mainly sinthesized in the fetal liver from placental precursors [13,22,29,31]. Therefore, we can't overlap the theoric value of these two parameters, but we have studied the possibility of compare these two assays s clinical parameters for testing the fetus-placental unity to have better informations about the well-being of the fetus [l, 18,29].…”

Radioimmunoassay of Unconjugated and Total Serum Estetrol Using a ¹²⁵I-Iodinated Tracer

“…Although it is difficult to explain the above differences, since many factors can be involved, it is worth remembering that Korda et al (3) and Fishman and Guzik (1) both use an antiserum with a 2.5% cross-reaction with E3, resulting in an overestimation of about 10%, as the authors themselves observe. As far as total E4 is concerned, the present data are substantially in keeping with the single literature reference so far available (7).…”

Estetrol: A unique steroid in human pregnancy

“…Starting around week 30, the E 4 plasma levels increase substantially as pregnancy progresses [31,32]. One study reported 7-fold higher values at week 40 when compared to week 22-26 [33].…”