Estratrienol is also known as Estra-5,7,9-triene-3b,17b-diol, or Hexahydroequilenin. It is a horse conjugated estrogen precursor.
Humans don’t produce conjugated estrogens.
Human estrogens include:
Estrone - (3-hydroxy-13-methyl- 6,7,8,9,11,12,13,14,15,16- decahydrocyclopenta[a]phenanthren- 17- one)
Estradiol - (17β-estra-1,3,5(10)-triene-3,17-diol; also 1,3,5(10)-Estratriene-3,17β-diol)
Estriol - (1,3,5(10)-Estratriene-3,16
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,17β-triol) Only produced in significant amount during pregnancy by the fetal liver from DHEAS; insignificant amounts produced in both men and women and men from androsterone precursor. The normal low level amount produced does not change with age (in men) or menopausal status (in women), but remains low and insignificant.
Estratetraenol - (8S,9S,13R,14S)-13-methyl-6,7,8,9,11,12,14,15-octahydrocyclopenta[a]phenanthren-3-ol;
also estra-1,3,5(10),16-tetraen-3-ol) - Only produced during pregnancy.
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Horse estrogens are a combination of non-conjugated and conjugated estrogens:
Estrone - the same as human, above
Equilin - 3-hydroxyestra-1,3,5,7-tetraen-17-one
Equilinin - 3-hydroxy-13-methyl-12,14,15,16-tetrahydro-11H-cyclopenta[a]phenanthren-17-one
Hexahydroequilenin (Estratrienol) - Estra-5,7,9-triene-3β,17β-diol
I’ve read that some of the conjugated estrogens become a very powerful free-radical in the human body, and this is problematic with taking horse steroids for hormone replacement therapy, which is the only estrogenic steroids approved for use in humans by the FDA for hrt. Go figure!
For other problems associated with conjugated estrogens from horses, please read here:
The picture below is from wiki
Diane