Why Does Everyone Let E2 Fly, But Still Worry About E2 from HCG?

I’ve noticed lately that everyone just lets E2 find its own level, and not mess with an AI or anything. Sounds good to me.

But why is it that everyone still worries about HCG raising E2? Does it raise it that much more than T alone?

1 Like

E2 is created in the testicles as well as through aromatase. On TRT, the testicle production dwindles and the only available avenue is via aromatase. When you introduce HCG, the testicles start producing again (T and E2). What I think most people worry about with that, is that there is no control mechanism for testicularly created E2. No AI (Aromatase Inhibitor) will touch it because it isn’t created via the aromatase process…

I don’t think that it should be much of a concern either way unless there are severe symptoms accompanying abnormal levels/ratios, but at least I hope this answers your question…


Makes sense! I recently started HCG again, and after just 250IU spread across a few days, I’m tired, bloated, and my libido has dropped. Softer erections too. And night sweats.

Gonna try to stick it out for a week or so though this time to make sure it’s actually related.

1 Like

Give it 6-8 weeks.

1 Like

HCG can take that long to level out? Or estrogen in general?

HCG has a short half life, but the effects of the extra production as a result of the HCG (T and E2) will take that long to stabilize.

1 Like

Just as a side, the E2 production at the testes is also via aromatase, it just doesn’t happen there without natural production because the endogynous test doesn’t get to those tissues.

1 Like

Ok not to be argumentative, but for my own understanding…

I’ve read it several times (undisputedly so) that an AI can’t touch E2 produced in the testes. If this is true, then how is it produced via aromatase?

Did you mean exogenous in this context?

I meant endogynous, thanks. And the reason is that there’s a barrier like the blood/brain barrier that blocks the AI from getting in there.

1 Like

Ok now I’m confused…

You’re saying “endogynous” (actually spelled endogenous) meaning “internal”, or do you mean indigenous, meaning naturally occuring?

Either way, they both would imply natural production in this context, so if I’m understanding you correctly, you are saying that naturally occurring testosterone cannot get to the testicular tissues, which doesn’t make sense.

Unless you meant that exogenous (foreign, outside, injected, etc…) can’t reach those tissues for the purpose of aromatase…which would actually make sense to my tiny little brain?

This is the entire sentence I’m asking about for context purposes…

I’m sincerely not trying to be a smart ass. I’m really trying to understand what you are saying here, because obviously I’m missing something! Lol

This I did not know. Thanks for explaining that!

I thought the reason AIs don’t work inside the testicles is because the level of testosterone inside the testicles (ITT - inter testicular testosterone) is much much higher than of that inside a normal blood sample. It seems to be separate to that of your blood test level. It only takes a bit of conversion with those high of levels to get high E2.

I think a barrier of some sort exists to allow ITT to be much higher than blood level testosterone. ITT seems to be correlated to sperm production and sperm health.

Basically a barrier exists for sperm production.

This was a lot of rambling, and I am not sure much of it makes sense (I think I sort of grasp it). Someone please correct me if I am wrong here.

1 Like

This . My brain isn’t working. I have dengue or something right now (Not even a joke)

They didn’t find evidence of aromatase there until sometime in the 90’s (late 90’s I think), so it was a mystery for a while.

I was confusing there, my fault. Time for something non-aspirin to lower my brain temp.

1 Like

wouldnt this be a benefit? then you wouldnt be able to crash your E2 through AI since there will always be some testicular E2 creation

It will be crashed everywhere else. E2 (according to a study I was reading) doesn’t get around too well. It would seem that your body relies on having aromatase enzyme everywhere and making the E2 where it needs it.

1 Like

ah so in that case it would just give you all the downsides with none of the benefits?

1 Like

It’s the other BBB (balls blood barrier🤣)…but seriously, it’s to keep sperm from floating all around your body otherwise the body would attack the sperm as it would a foreign invader.