hCG (Human Chorionic Gonadotropin) for Testicular Function — Testosterone & Androgens
LH-mimetic gonadotropin that maintains testicular size, intratesticular testosterone, and fertility during TRT.
Overview
Human chorionic gonadotropin (hCG) is a glycoprotein hormone that shares structural homology with luteinizing hormone (LH) and binds to the LH/CG receptor on Leydig cells in the testes. During testosterone replacement therapy, exogenous testosterone suppresses the HPG axis, reducing endogenous LH secretion and leading to testicular atrophy, decreased intratesticular testosterone (ITT), and impaired spermatogenesis. hCG administration maintains Leydig cell function and ITT levels, preserving testicular volume and fertility potential. Studies demonstrate that hCG 500 IU every other day maintains ITT at approximately 25% of baseline (versus near-zero without hCG) and preserves qualitative spermatogenesis in most men on TRT. hCG is FDA-approved for hypogonadism, prepubertal cryptorchidism, and is an essential component of fertility treatment protocols. Following the FDA's 2020 reclassification of hCG as a biologic, compounding pharmacy production was restricted, increasing costs and access challenges. Recombinant hCG (Ovidrel) and urinary-derived formulations (Pregnyl) remain available.
Indications
- FDA-approved: Male hypogonadotropic hypogonadism
- FDA-approved: Prepubertal cryptorchidism
- FDA-approved: Ovulation induction in women (with menotropins)
- Off-label: Testicular function preservation during TRT
- Off-label: Fertility preservation in men on testosterone
- Off-label: Post-cycle therapy component
Mechanism of Action
hCG binds to the LH/CG receptor on testicular Leydig cells with high affinity, mimicking the action of endogenous LH
Dosing
| Compound | Dose | Frequency | Notes |
|---|---|---|---|
| hCG | 500 IU | Every other day | Standard TRT adjunct dose for testicular preservation |
| hCG | 250 IU | Every other day | Low dose — adequate for many patients with lower aromatization |
| hCG | 1000 IU | Three times weekly | Fertility protocol — higher dose for spermatogenesis |
| hCG | 1500-4000 IU | 2-3x weekly x 6-12 weeks | FDA-approved hypogonadism protocol |
Evidence Grade
GRADE B
Safety & Contraindications
- May increase estradiol significantly — monitor and manage with AI if needed
- Injection site reactions (pain, swelling, bruising)
- Headache and irritability reported
- Gynecomastia risk due to estrogen elevation
- Overstimulation of Leydig cells possible at high doses
- Desensitization of LH receptors possible with very high or continuous dosing
- Since 2020 FDA reclassification as biologic, compounding restricted