How much does Estradiol generally vary between injections?

[andromeda]

If one was on a standard protocol of twice weekly injections, with a normal mid-range SHBG levels, how much could you expect Estradiol to vary between peak and trough levels? For example if someone had an E2 sensitive reading of something like 20 at their trough. Thanks.

 

[CoastWatcher]

How much testosterone are you injecting? Is your protocol stable? Are you using hcg? If so, how much? How much body fat? No AI? Mid-ranfe SHBG...meaning? Little in this game is linear.

E follows T: your trough testosterone reading is not necessarily coincident with your trough estradiol value.

 

[Cataceous]

If you have reasonable estimates of your peak and trough testosterone levels then the trough estradiol will let you calculate a decent estimate of peak estradiol. If you're willing to accept even less accuracy then you can estimate peak testosterone by working backwards from the trough and assuming a particular half-life for your testosterone ester and time for the peak.

 

[Systemlord]

If one was on a standard protocol of twice weekly injections, with a normal mid-range SHBG levels, how much could you expect Estradiol to vary between peak and trough levels? For example if someone had an E2 sensitive reading of something like 20 at their trough. Thanks.

Your question is dependant on so many factors, it's impossible to answer accurately. There are so many factors that determine these fluctuations, individual biology, body fat percentage and the binding force of your SHBG.

 

[Vince Carter]

There's no part of this that is that linear.

 

[Cataceous]

If one was on a standard protocol of twice weekly injections, with a normal mid-range SHBG levels, how much could you expect Estradiol to vary between peak and trough levels? For example if someone had an E2 sensitive reading of something like 20 at their trough. Thanks.

Setting aside the pessimism of my colleagues, I'll try to at least put limits on the number: Assume the following:

• E3.5D injections
• Trough estradiol of 20 pg/mL
• Serum testosterone peaks reached one day after injections
• Exponential decay from peaks with 6-day half life

Under these conditions serum testosterone is expected to drop 25% from peaks to troughs. Neglecting the time lag in estradiol you would expect to see estradiol drop in proportion to testosterone. This sets an upper limit for peak estradiol at about 27 pg/mL. Derating this for dynamic estradiol gets trickier. One study on normal males showed relative diurnal estradiol variation to be as little as 40% of testosterone variation. This figure can be used to derive a lower limit on peak estradiol of 22 pg/mL. So the answer in this example is that peak estradiol is expected to be around 22-27 pg/mL.