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Updated: Aug 19, 2026

The 4-vessel Sampling Approach to Integrative Studies of Human Placental Physiology In Vivo
Published on: August 2, 2017
[Concepts of placental hormonology]
Abstract:
During pregnancy, different protein (hCG and hPL) and steroid (progesterone, oestradiol, oestrone, oestriol) hormones are secreted. hCG, measured by RIA in maternal serum, is a first-trimester trophoblastic function test. The serum levels of hPL reveal the placental function during the two last trimesters of gestation. The main steroid hormones, produced by the foeto-placental unit, are progesterone, oestradiol and oestrone, which control placental function, and oestriol, a good index of foetal vitality.
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