Head to head
HCG against Gonadorelin
Two ways to keep the testes working during testosterone therapy, one acting downstream at the testis and one upstream at the pituitary. Gonadorelin's natural pulsatility is difficult to reproduce with intermittent injections, which is the practical objection to it.
Column A
HCGHuman Chorionic Gonadotropin
An FDA-approved gonadotropin used in fertility and to maintain testicular function and testosterone production in men.
Column B
GonadorelinGonadorelin (synthetic GnRH)
Synthetic gonadotropin-releasing hormone, historically approved for diagnosis and fertility and now used to preserve testicular function during testosterone therapy.
Side by side, on the facts we can check
| Attribute | HCG | Gonadorelin |
|---|---|---|
| Category | Hormone | Hormone |
| FDA status | FDA-approved for fertility and hypogonadism (not for weight loss) | Previously FDA-approved (diagnostic/fertility); used off-label and compounded in TRT |
| Half-life | ~24-36 hours | ~2-4 minutes |
| Molecular weight | ~36,700 Da | 1,182.3 Da |
| Mechanism | Activates LH receptors to stimulate testicular testosterone production and, in women, support ovulation and the corpus luteum. | Stimulates pituitary release of LH and FSH when given in pulses, mimicking natural GnRH signaling; continuous exposure instead desensitizes and suppresses it. |
| Human studies cited | 2 | 1 |
| Legal status, US | FDA-approved, prescription only | Prior approvals largely discontinued; available via compounding, prescription only |
Frequently asked questions
What is the difference between HCG and Gonadorelin?
HCG: An FDA-approved gonadotropin used in fertility and to maintain testicular function and testosterone production in men. Gonadorelin: Synthetic gonadotropin-releasing hormone, historically approved for diagnosis and fertility and now used to preserve testicular function during testosterone therapy.
Which has stronger research evidence, HCG or Gonadorelin?
This database does not grade compounds. It counts what was run in people: 2 of the 4 studies cited on the HCG profile were human work, against 1 of 2 for Gonadorelin. Those counts are of our own citation lists and understate any larger literature, and neither is a recommendation.
Are HCG and Gonadorelin FDA-approved?
HCG: FDA-approved for fertility and hypogonadism (not for weight loss). Gonadorelin: Previously FDA-approved (diagnostic/fertility); used off-label and compounded in TRT.
Reviewed Sep 2026. This page sets two published records side by side. It is educational, it is not medical advice, and it contains no dosing protocols or recommendations for personal use.