hcg
A placental glycoprotein hormone that activates the LH receptor. Product form and labeled route matter.
tier S · libido · 32 to 33 h terminal half-life in an 18-woman Pregnyl crossover
verdict
HCG has established fertility and selected male endocrine uses. Small human studies support intratesticular-testosterone and semen preservation during testosterone therapy, but that adjunct use remains off-label. HCG does not cause weight loss.
why S-tier
Current labels and a deep fertility record support the established clinical lane. The testosterone-adjunct question has smaller human studies, and the diet claim fails controlled review.
the core tension
HCG is established reproductive medicine. The common testosterone-adjunct lane has human support but remains smaller and off-label, while the weight-loss lane is contradicted.
what it is
Human chorionic gonadotropin is a placental glycoprotein hormone, not a short peptide. Urinary Pregnyl and Novarel are intramuscular products. Recombinant choriogonadotropin alfa, sold as Ovidrel, is a separate subcutaneous product.
what it does
HCG activates the LH/CG receptor. In testes, that signal drives Leydig-cell testosterone production. In ovaries, it supports final follicular maturation and ovulation. The receptor mechanism is shared, but products, routes, and indications are not interchangeable.
origin
Current US labels identify Pregnyl and Novarel as urinary hCG and Ovidrel as recombinant choriogonadotropin alfa. FDA's 2020 transition moved qualifying hCG products into biologics regulation and changed the compounding pathway; it did not turn community protocols into labeled uses.
does it work
In a 29-man randomized study, subcutaneous hCG preserved intratesticular testosterone during weekly intramuscular testosterone. In a separate uncontrolled 19-man cohort that continued non-prescribed androgens, mean total sperm count rose from 18.0 million to 146.9 million after three to six months, but some men remained oligospermic or azoospermic. Controlled review found no hCG weight-loss benefit.
key facts
- molecular formula: glycoprotein with alpha and beta subunits
- molecular weight: product and glycoform dependent
- amino acids: glycoprotein hormone, not a short peptide
- half-life: 32 to 33 hours in one Pregnyl IM and SC crossover
- type: LH/CG-receptor agonist
- 32 to 33 h Pregnyl terminal half-life
- 18 participants in the route crossover
- 29 men in the intratesticular-testosterone study
- 26 men in the semen cohort
- 0 benefit weight-loss conclusion
frequently asked questions
Are Pregnyl and Novarel subcutaneous products?
Their current US labels specify intramuscular use. A randomized Pregnyl crossover found comparable total exposure after 10,000 IU IM and SC in 18 pituitary-suppressed women, but that does not make every product, dose, and indication interchangeable.
Is Ovidrel the same product?
No. Ovidrel is recombinant choriogonadotropin alfa in a subcutaneous prefilled syringe. Pregnyl and Novarel are urinary hCG products labeled for intramuscular use.
What did the testosterone studies show?
A 29-man randomized study found dose-related preservation of intratesticular testosterone. A separate uncontrolled 26-man cohort reported preserved semen parameters. Those findings support a narrow off-label rationale, not a guaranteed fertility outcome.
Does the hCG diet work?
No. A meta-analysis found no evidence that hCG improves weight loss, fat distribution, hunger, or well-being, and FDA states that hCG is not approved for weight loss.
Can FAERS show how often hCG causes an adverse event?
No. Spontaneous reports have no exposure denominator and cannot establish incidence, relative risk, or causality.
related peptides
- gonadorelin: upstream GnRH signal with pulse-dependent delivery
- triptorelin: GnRH agonist used for sustained suppression
reptides grades the research record and cites the literature behind every call. research reference only; not medical advice.