What is Human Chorionic Gonadotropin?

Human Chorionic Gonadotropin (abbreviation: HCG) is not a steroid. It is a naturally occurring peptide hormone which in the early stages of pregnancy is produced by the embryo and later the production is taken over by the trophoblast (part of the placenta). Its main purpose is to control a pregnant womans hormones. Human chorionic gonadotropin supports the normal development of an egg in a woman's ovary, and stimulates the release of the egg during ovulation.

HCG binds to the same receptor and is molecularly similar to Leutenizing Hormone (LH) - a hormone which stimulates the leyding cells in male testes which then produce testosterone. Because of this similarity hCG is used to start testosterone production in the male testes or ovulation in the female ovaries.

Intended use of HCG

Human Chorionic Gonadotropin is primarily used as fertility aid. In women it triggers ovulation while in men it increases testosterone production and sperm count. HCG is also used in young boys when their testicles have not dropped down into the scrotum normally.

Because some cancers excrete HCG it can also be used as a tumor marker. A positive HCG test result in males (who are not otherwise injecting HCG) can be an indicator of testicular cancer or germ cell tumors.

HCG in PCT (post cycle treatment)

In bodybuilding pharmacology HCG is one of the most misunderstood, misused and underutilized tools available. A bodybuilder who cares about his body functioning properly should never sacrifise his health for muscle gains. After every anabolic steroid cycle, the body's own testosterone production has to be fully restored.

When external androgenic anabolic steroids (AAS) are introduced into the male body the natural negative-feedback loop causes the body to shut down its own production of testosterone via shutdown of the hypothalamic-pituitary-gonadal axis (HPGA). In other words, when the body senses there is too much testosterone flowing around, it stops producing more of it.

High levels of anabolic steroids, which mimic the body's natural testosterone, cause the hypothalamus to stop its production of gonadotropin-releasing hormone (GnRH). Without GnRH, the pituitary gland stops making the luteinizing hormone (LH). Without LH, the testes shut down the body's production of testosterone.

The longer the testes are not getting the lutheinizing hormone, the more the cells within the testes known as leydig cells - (which are normally activated by LH) become desensitized. The testicular degeneration starts with reduction of leydig cell volume, followed by rapid reductions in intra testicular testosterone (ITT), peroxisomes, and Insulin-like factor 3 (INSL3). This is the reason why some men never completely recover after a long steroid cycle. In such cases the testes have stayed inactive for too long and have become permanently damaged and desensitized.

HCG during AAS cycle (Human Chorionic Gonadotropin during steroid cycle)

To prevent permanent shutdown of testosterone production a low dose of human chorionic gonadotropin (250IU 2 or 3 times per week) is used during the steroid cycle. One has to be careful and avoid dosing too high or too frequently as that can also desensitize the testes. The HCG dosage and the interval has to be just right to stimulate the leydig cells to produce the same amount of testosterone as they normally would. The saying more is better definitely does not apply to the use of HCG. Human chorionic gonadotropin has to be continued for as long as the steroids are active in the body and preferably 1-2 week beyond.

Leydig Cell Desensitization:
Desensitization basically means unresponsive. Your Leydig cells are stimulated by the LH signal. If they no longer respond to LH, you will not produce testosterone.

There are 2 ways that could potentially desensitize Leydig Cells:

1. Prolonged LH deprivation: When you inject steroids, your LH production is halted at the pituitary, remember? So if you continue in a suppressed state for weeks upon weeks, your Leydig Cells could potentially become unresponsive, or desensitized. It is possible to reverse desensitization of the cells, but that has been proven to be quite a difficult task. So when you use hCG on cycle, the mimicked LH analog will maintain stimulation of Leydig cells so that you don't run the risk of rendering them useless. This level of maintenance will ensure a much healthier and speedy recovery and one of the most important reasons to use hCG on cycle.

2. Over stimulation of Leydig cells: There is no reason to use more than 500 IU of hCG at one time. And certainly not a good idea to run even that dose on a daily basis. You do not have an unlimited-ever-flowing-supply of Leydig cells. There is only so much stimulation hCG can do. What happens when you dose hCG really high, is that you're increasing intra-testicular estrogen. So you're thinking that you could use an aromatase inhibitor in that case, right? Nope. AI's are not effective treatment for intratesticular e2. Furthermore; high doses is a surefire way to desensitize Leydig Cells. So we have a double whammy here. And this is just another reason to use hCG on cycle, and not "blast" hCG post cycle leading up to and/or during PCT.

Why you should use HCG ON cycle:

We know that steroids shut down production of LH at the pituitary. This means you no longer produce natural testosterone because there's nothing to stimulate your Leydig Cells in the testes. The reason your testicals normally look "full", is because they're loaded with testosterone. When your natural testosterone production is suppressed, your testes atrophy (shrink), because they're empty. Make sense?
Injecting HCG results in a "mimicked" LH. So although your pituitary gland is not secreting LH, your leydig cells, in the presence of HCG, are stimulated by the mimicked LH and begin to produce testosterone. So there's your solution for preventing testicular atrophy while on cycle. But there's more to HCG than just reversing atrophy. Let's have a quick look at some other reasons to use HCG.

Benefits of HCG during your cycle:

1. Prevention of testicular atrophy.
   -- This is done by mimicking LH and restarting natural testosterone production in the testes.

2. Speed up recovery.
   -- This is done by mimicking LH so that your Leydig cells remain stimulated. More on this in the next segment.

3. Balances hormonal fluctuation. (Mainly TRT patients and dose dependant)
   -- By strategically timing hCG injections, you will prevent "dips" in serum levels.

4. HCG in involved in the process of production for DHEA, Cortisol and Pregnenolone.
   -- A host of benefits here. These benefits will combat fatigue and stress, betters your mood, has a role in energy, reduced cardiovascular risk, immune stimulation, betters memory, and more.

Why You Should Not Use HCG Post Cycle: (maybe right before but not during)

Let's establish what we are trying to accomplish here. You just got done with your cycle and you've been suppressed for however many weeks. We want to bring our natural HPTA back to life, can we all agree on that? If you said no, please ask Mom if she dropped you on your head when you were a baby. Moving on...
HCG is suppressive! Since we know that hCG mimics LH, then we know that in the presence of exogenous LH, the pituitary gland will not produce LH.

How to determine your HCG dosage for post cycle treatment (PCT)
The HCG dose in the post steroid cycle treatment depends on the severity of testosterone shutdown which was caused by steroids. If HCG was used during the cycle itself, the shutdown of endogenous testosterone would be less severe as compared to a long steroid cycle without HCG (stimulation of leydig cells in the testes).

To determine the proper dosage of HCG one has to consider these 4 decisive factors:

• Duration of the steroid cycle: the longer the recent cycle, the more suppressed the leydig cells will be and the more Human Chorionic Gonadotropin the person will need to "shock" them back into action and make them start the natural testosterone production again.
• Age of the user: generally older people require higher dosage of HCG to stimulate the leydig cells and testosterone production.
• Accumulated damage to leydig cells: if the user has been cycling steroids for years and sometimes experienced incomplete testosterone recovery, it will be more difficult to recover each time. The more past damage has been accumulated to the leydig cells, the longer the user will have to stay on the HCG therapy followed by a longer pause between steroid cycles.
• During the recent steroid cycle, did the user allow for full shutdown of the natural testosterone production or was there some kind of protection used to keep the leydig cells active (for example low dose HCG).

A must read for everyone: (Thanks giardap):

https://www.eroids.com/forum/steroids-qa/pct-anti-estrogens/pct-its-hist...

https://www.eroids.com/forum/steroids-qa/pct-anti-estrogens/hcgpct-quest.... (go to the comments and find one from 2 months ago)

Ps. All the info in this post has been found online or in books (not claiming its my own writing or anything) as vets comment with info or if they find any mistakes I will be correct and update the post.

Some of the info has been taken from:
http://steroid.es/hcg.html
https://www.linkedin.com/pulse/hcg-why-you-should-use-on-cycle-only-how-...
https://brotherhoodofpain.com/archive/index.php/t-12647.html
https://www.diyhcg.com/2017/01/%E2%80%8Badjustments-to-hcg-dosages-durin...
https://www.quora.com/How-should-HCG-be-used-in-bodybuilding-Is-Tamoxife...
http://www.steroids.org/HCG.php