hCG
Human Chorionic Gonadotropin
Human chorionic gonadotropin (hCG) is a glycoprotein hormone naturally produced during pregnancy that acts on LH receptors to stimulate gonadal function. It is one of the most extensively studied hormones in reproductive endocrinology, with decades of published clinical data. Researchers use hCG to investigate LH-receptor-mediated processes including testosterone production, ovulation, and gonadal function maintenance.
Aliases: Human Chorionic Gonadotropin
- Research score
- 10/10
Mechanism
Human chorionic gonadotropin (hCG) is a glycoprotein hormone produced by trophoblast cells of the placenta. Its alpha subunit is identical to LH, FSH, and TSH; the beta subunit confers specificity. hCG binds to LH/CG receptors on Leydig cells in the testes, activating adenylyl cyclase/cAMP signaling, which stimulates cholesterol conversion to pregnenolone and downstream steroidogenesis (testosterone synthesis). Also supports Sertoli cell function and spermatogenesis. In women, stimulates ovulation via LH-like activity.
Evidence note
Established — FDA-approved, decades of clinical use. Robust human data for fertility, hypogonadism, and TRT support. One of the most studied peptides/hormones in this list.
Community evidence
- Source window English Reddit Updated 12 Aug 2026 · 6-month window
- Coverage confidence Low Confidence in the available community sample
- Distribution Pending Not enough data for a distribution.
Selected reports
No qualifying Reddit reports about this exact product were found in the current source window.
Based on 0 qualifying reports from 0 threads. 36 candidates excluded as duplicates, promotion, deleted content, or lacking concrete personal experience. Reddit self-reports are not medical evidence or proof of causation.
Studies
Human chorionic gonadotropin for management of infertility in hypogonadal men
hCG maintains spermatogenesis in men on TRT and prevents azoospermia. Essential for fertility preservation during testosterone replacement.
Open source · PMID 30087849hCG concurrent with testosterone replacement therapy
Prevents testicular atrophy during TRT by maintaining intratesticular testosterone at levels sufficient for ongoing spermatogenesis and Leydig cell function.
hCG in post-cycle therapy and Leydig cell restoration
Restores Leydig cell function post-AAS use with dose-dependent testosterone response. Current community meta favors on-cycle use over standalone PCT.
FAQ
Why is hCG dosed in IU instead of mcg like other peptides?
hCG is a glycoprotein hormone (not a simple peptide), and its biological activity is measured in International Units (IU) rather than by mass. This is because the biological potency can vary between preparations, so IU standardizes the actual biological effect. A standard vial contains 10,000iu. Typical TRT support dosing is 250-500iu every other day or 3x per week.
Should hCG be used during TRT or only for PCT?
Current consensus strongly favors using hCG concurrently with TRT (on-cycle) rather than only for PCT. On-cycle use maintains testicular size, intratesticular testosterone, and spermatogenesis throughout. Using hCG only post-cycle means the testes have already atrophied and recovery takes longer. The typical on-cycle dose is 250-500iu every other day or 3x/week.
Does hCG need to be refrigerated?
Yes. Lyophilized (powder) hCG should be stored refrigerated for best stability. After reconstitution with bacteriostatic water, it MUST be refrigerated and used within 30-60 days. hCG is a large glycoprotein hormone that is more sensitive to temperature than smaller peptides. Never freeze reconstituted hCG.
For research and educational use only. This content is not medical advice.