Chorionic gonadotropin is a glycoprotein consisting of 244 amino acids with a molecular weight of up to 36.7 kDa. It is a heterodimer consisting of an α subunit identical to luteinizing hormone (LH), follicle stimulating hormone (FSH), thyroid stimulating hormone (TSH), and a β subunit that are unique in hCG. It occurs in women in early pregnancy and is produced in the placenta. The presence of this hormone is recorded only during this period, which is why some of the pregnancy tests available in pharmacies are based on HCG. The level of the hormone in the blood rises 7 days after ovulation. Then it grows slowly and steadily until the 2nd or 3rd month of pregnancy. After this period, hCG levels decline until delivery. This drug is obtained by extraction from the urine of pregnant women. The action of chorionic gonadotropin is similar to that of LH. The drug stimulates the production of sex steroid hormones in interstitial cells – testosterone. There are as many as 4 versions of this substance available in Poland: Biogonadyl (Biomed-Lublin), Choragon (Ferring Pharmaceuticals), Pregnyl (the international concern Organon) and Profasi (Serono). Like other gonadotrophins, hCG can be extracted from urine or produced by genetic modification. Pregnyl, Follutein, Profasi and Novarel are the use of the first method, derived from the urine of pregnant women. Ovidrel is a recombinant DNA product
In medicine, HCG is used in the therapy of, inter alia, infertility in women with gonadotropin deficiency, infertility in men with hypogonadotrophic hypogonadism, Disorders of testicular descent, not due to anatomical obstruction.
In bodybuilding, hCG is of no benefit to female athletes, but is very useful for men using anabolic androgenic steroids. It helps to stimulate the secretion of endogenous testosterone. In the male body, HCG mimics LH, a natural hormone secreted by the pituitary gland that stimulates the Leydig cells in the testes to produce testosterone. Such action is especially valuable in the period shortly after the end of taking steroids, when the proper functioning of the HPTA should be restored as soon as possible. Too low levels of androgens after the cycle can be very detrimental to the body. The main problem is the lack of androgens, another high level of cortisol, determined by the level of androgens. As it is known, cortisol in superphysiological amounts is a highly catabolic hormone that causes the breakdown of muscle tissue. Failure to take appropriate measures to minimize his activity will lead to the loss of most of the previously acquired muscle mass. Sometimes hCG is also used periodically in small doses (500 I) during long cycles to prevent the testes from drastically shrinking.
The most important task of HCG is to restore the proper reaction of the testes to endogenous luteinizing hormone (LH). This ability can be severely impaired as a result of prolonged deactivation. Even restoring normal LH secretion in such a case will not lead to adequate secretion of endogenous testosterone. HCG also helps to restore the testicles to their normal size after they have become slightly atrophied as a result of prolonged use of AAS. Misuse of Placental Gonadotrophin can be quite harmful. High testosterone levels caused by HCG can block the proper functioning of the hypothalamus, just like injectable testosterone. In addition, an increased level of estrogen may occur as a result of the stimulation of aromatase activity in Leydig cells. HCG increases the activity of iAMP (regulator of cellular activity), therefore the ability of the testes to aromatize androgens under the influence of HCG increases even several times. HCG should therefore only be used as an immediate stimulus for the testicles.