Overview and history of HCG
Human chorionic gonadotropin (HCG) is a protein hormone (or peptide hormone) that is produced naturally and endogenously in a woman's body by the syncytiotrophoblasts of the placenta.
In women, HCG plays a very important role in stimulating the release of progesterone, a hormone essential for pregnancy.
HCG that is bottled for human use is obtained from humans, not synthesized in nature.
It is found in very high concentrations, especially in pregnant women, as mentioned earlier.
HCG is actually used as the primary sign of pregnancy in women because it is only present in very high amounts in women during pregnancy.
HCG is the substance that home pregnancy tests detect in urine, and when present in significant amounts, the home pregnancy test will turn blue.
In pregnant women, the increase in HCG in the body increases very quickly and can be detected within 7 days of the increase in secretion.
However, HCG levels only begin to rise at this time, and plasma HCG levels do not actually peak until about 2-3 months after conception.
After these two to three months, HCG levels begin to decline.
While HCG itself can technically be considered synthetic LH (luteinizing hormone) and FSH (follicle-stimulating hormone), HCG is actually a different hormone, but in men, it mimics the actions of LH and FSH equally.
LH and FSH are gonadotropins produced and secreted by the pituitary gland, and in men, these two hormones signal the Leydig cells in the testes to start or increase the production of testosterone.
The term 'gonadotropin' refers to any compound or hormone that stimulates the gonadal organs (testes in men, ovaries in women).
In women, LH and FSH trigger ovulation (the production of an egg in the ovaries). HCG is medically administered to women suffering from infertility (perhaps due to their inability to endogenously produce sufficient levels of gonadotropins or for other reasons) because it is essentially a mimetic of LH and FSH in terms of physiological activity.
In the medical community, HCG is also administered to men to treat hypogonadism (low androgen production).
It is also used medically in the treatment of delayed puberty in adolescent males and in the treatment of prepubertal cryptorchidism (during or after puberty), a condition in which an individual's testicles descend improperly.
Among the anabolic steroids used by bodybuilders and athletes, HCG has long been utilized for its ability to restore endogenous testosterone production after an anabolic steroid cycle has ended.
This is a period of time when hormonal recovery is essential, and HCG is typically inserted into a compound protocol for approximately 4-6 weeks after the end of an anabolic steroid cycle, known as Post Cycle Therapy (PCT).
Human chorionic gonadotropin (HCG) was discovered in 1920 when an HCG extract from the human placenta was administered to rabbits and its effects were observed [1].
Then, in 1928, it was realized that HCG was actually an essential hormone for all roles related to pregnancy [2].
Soon after, the first HCG preparations derived from the pituitary glands of various animals were developed and tested, and in 1931, Organon began selling it to the prescription drug market under the name Pregnon.
Eventually, in 1932, the trade name was changed to Pregnyl, the trade name by which HCG is universally known.
Organon still manufactures, markets, and sells Pregnyl today, but it is not made from pituitary gland extract.
Eventually, advances in technology in the 1940s made it possible to extract HCG from pregnant women's urine through filtration and purification in the laboratory, and by the 1960s, all HCG pharmaceutical manufacturers had adopted this method.
Today, this is still the way HCG is manufactured, and while other methods have been developed, extracting HCG from pregnant women's urine remains the most effective, efficient, and cost-effective method.
When HCG first came into widespread use in the medical community in the 1950s and 1960s, the medical indications for which it was approved for treatment were very broad.
They included a variety of medical indications, including treatment of uterine bleeding, Froelich's syndrome, cryptorchidism, female infertility, depression, male infertility, and hypogonadism.
Eventually, in the 1970s, when the FDA tightened its grip on the prescription drug market, the list of approved treatments was significantly reduced, and today HCG is only used to treat hypogonadism and cryptorchidism in men and infertility in women.
Contrary to popular rumor, HCG is not effective for fat loss, nor does it have the ability to stimulate the thyroid gland to produce more thyroid hormone.
This is especially important to clarify because for a long time, HCG was misused and misinterpreted to treat obesity, stemming from a 1954 study.
This study claimed that subjects lost a significant amount of body fat after using HCG while maintaining an extremely low calorie intake (500 calories per day).
Many people misinterpreted this study, focusing on the fact that HCG was used without considering the calorie deficit of the subjects.
More than 30 years later, the entire study and obesity treatment centered around HCG was revisited, and its approved use for obesity treatment was revoked [3].
Little did people know at the time that severe calorie restriction causes the body to lose critical lean tissue (muscle) and vital organ tissue in order to preserve itself, and that the consequences of severe calorie deficit are worse for the body than obesity.
Eventually, in 1974, the FDA even issued a statement on all pamphlets packaged with HCG stating that using HCG for fat loss was not effective and should not be used as such.
Today, HCG is still widely used in medicine and is widely available in all markets around the world under a variety of major brand names (Organon's Pregnyl, Serono's Profasi, Ferring's Novarel, etc.), with many generic versions of HCG also available.
HCG is not a controlled substance in nearly every country in the world, including the United States (where it is still available by prescription only, but not as a controlled substance).
Because of its immense popularity, oversupply in the market, and ease of manufacture, counterfeits and fakes are not a problem.
Chemical Properties of HCG
Human chorionic gonadotropin (HCG) is a protein (or peptide) hormone, but more specifically, it is referred to as an oligoglycoprotein (a glycoprotein with one or more carbohydrate/sugar molecules attached to the protein molecule).
The protein structure consists of an amino acid chain of 244 amino acids, followed by subunits of 92 amino acids that are 100% identical to LH and FSH.
It is this subsection of the HCG molecule that is able to mimic the actions of LH and FSH with 100% identicality at the same receptors on the cells that LH and FSH activate.
Properties of HCG
The primary purpose of HCG is to treat infertility in women or to stimulate and/or increase endogenous testosterone production in men.
HCG is generally very well tolerated by most men who use it for hormonal recovery after discontinuing an anabolic steroid cycle.
There have been many misconceptions about HCG, especially since its introduction into the world of anabolic steroid use, so there are two HCG side effects that every individual should be aware of before using it.
HCG Side Effects
Estrogenic Side Effects
We have previously discussed in this profile that HCG increases testicular aromatase activity, which can lead to estrogenic side effects due to increased estrogen produced by the aromatization (conversion) of androgens into estrogen.
Therefore, it is recommended that an aromatase inhibitor (AI) be used during HCG use, and as previously discussed, the best AI for this purpose is Aromasin (Exemestane).
Other AIs can be used, but the use of two other commonly known AIs (Letrozole and Arimidex) can cause issues with the typical PCT protocol of HCG, Nolvadex, and an aromatase inhibitor.
This was covered extensively in the HCG dosing portion of this profile.
The use of AIs to lower circulating aromatase and estrogen levels can lead to estrogenic side effects as well as impairment of endogenous HPTA function.
This can be counterproductive to the original goal of restoring hormonal function.
Estrogenic side effects include water retention and bloating, increased blood pressure (due to water retention), increased likelihood of fat retention/gain, and gynecomastia.
Androgenic side effects
Androgenic side effects are actually part of the HCG side effects because HCG increases circulating plasma levels of androgens such as testosterone, specifically dihydrotestosterone.
This is a naturally expected and desirable effect from HCG use.
Androgenic side effects include increased sebum secretion (oily skin), increased acne breakouts (associated with increased sebum secretion), increased body and facial hair growth, and an increased risk of developing benign prostatic hyperplasia (BPH) and male pattern baldness (MPB) (in those who have the genetic traits necessary to develop these conditions).
HCG references
[1] Exogenous stimulation of luteinization in the rabbit; effects of human placenta, decidua, fetus, dropsy and luteal extracts on rabbit gonads. Hirose T 1920 J Jpn Gynecol Sot 16:1055.
[2] Die Schwangerschaftsdiagnose ausdem Ham durch Nachweis des Hypophysenvorderlappen-hormone.11. Pracktishe und theoretische Ergebnisse aus den hamuntersuchungen. Ascheim S/ Zondek B 1928 Klin Wochenschr 7:1453-1457.
[3] Effectiveness of human chorionic gonadotropin (HCG) in the treatment of obesity with simeon therapy: a criteria-based meta-analysis. Lijesen GKS, et al. Br J Clin Pharmacol1995; 40: 237-43.
