E2 is the product of T–>E2 and is the main focus. E1 and E3 are typically side shows. We can control E2 and get good results.
E1 - estrONE
E2 - estraDIol
E3 - esTRIol
E2 does not provide any kind of measure of T.
E2 opposes the effects of T
E2 increases SHBG that decreases FT. So FT:E2 take a double hit.
We do not seem to have a need to worry about fE2 vs E2+SHBG
E2+SHBG is bio-available, T+SHBG is not
There is a Estradiol sticky found here: About the T Replacement Category - #2 by KSman
Also see: Steroid hormone - Wikipedia
