HCG: The Fertility-Preserving Hormone for TRT & Beyond
Last updated: March 2026
Human Chorionic Gonadotropin mimics LH to keep your testes producing testosterone — even on TRT. It's the reason men on testosterone replacement can still have kids. But FDA changes in 2020 shook the entire supply chain.
Dose Per Injection
Frequency
Reclassification Year
📋 On this page
How HCG Works
HCG is structurally similar to luteinizing hormone (LH) and binds to the same receptors on Leydig cells in the testes. When exogenous testosterone shuts down your HPT axis, HCG steps in where LH can't.
HCG binds to LH/CG receptors on testicular Leydig cells with high affinity. This triggers the same intracellular cAMP cascade as natural LH — stimulating cholesterol conversion to pregnenolone, the first step of steroidogenesis. The result: local testosterone production in the testes even when pituitary LH is suppressed by exogenous testosterone. (Rivier & Vale, Endocrinology, 1985)
Testes need 40-100x higher testosterone concentrations than serum for spermatogenesis. Exogenous TRT kills this gradient. HCG at 250-500 IU 2-3x/week maintains ITT at ~25% of normal — enough to preserve spermatogenesis in most men. Without HCG, testicular atrophy begins within 2-4 weeks of TRT. (Coviello et al., JCEM 2005)
HCG is the primary tool for maintaining fertility on TRT. It preserves Sertoli cell function and the spermatogenic niche. Studies show that men on TRT + HCG maintain sperm counts sufficient for natural conception in ~65-70% of cases, vs near-zero with TRT alone. For active fertility attempts, HCG may be combined with FSH (e.g., Gonal-F). (Wenker et al., J Urol 2015)
HCG stimulates not just testosterone but also aromatase activity in the testes. This means more estradiol production — proportionally more than from testosterone alone. Higher HCG doses (>1000 IU) can spike estrogen significantly, requiring aromatase inhibitor management. This is why moderate dosing (250-500 IU) is preferred as a TRT adjunct.
What the Clinical Evidence Shows
Data from published studies on HCG for hypogonadism, fertility preservation, and testosterone production.
Side Effects & Risks
HCG is generally well-tolerated at standard TRT adjunct doses. Most issues arise from estrogen elevation at higher doses.
Study Citations
Key Takeaways
- HCG mimics LH and maintains testicular function during TRT
- 250-500 IU 2-3x/week preserves intratesticular testosterone and fertility
- Prevents testicular atrophy on exogenous testosterone
- HCG monotherapy can increase T by 50-100% in hypogonadal men
- 65-70% of men maintain viable sperm counts on TRT + HCG
- FDA-approved for hypogonadism and fertility (brand-name versions)
- Long-term effects of continuous HCG use beyond 5 years
- Optimal dosing for fertility vs testicular maintenance
- Whether Leydig cell desensitization occurs at standard doses long-term
- Full impact of 2020 FDA reclassification on long-term availability
- HCG's effect on prostate health with extended use
- Individual variation in aromatase activity response
🛒 Recommended Products
Injection supplies and support products for HCG protocols.
Affiliate links help support HighPeptides at no extra cost to you.
Related Resources
Want the Complete Protocol Guide?
Dosing schedules, interaction warnings, and cycle protocols for 50+ compounds — all in one place.
Get the Guide →
This page is for educational and informational purposes only. It is not medical advice. HCG is a prescription medication in the United States and most countries. Since 2020, the FDA has reclassified HCG as a biologic, affecting compounding pharmacy availability. HCG should only be used under the supervision of a licensed healthcare provider. The "HCG diet" is not supported by clinical evidence and is not endorsed by the FDA. HighPeptides does not sell HCG or endorse its use outside of legitimate medical supervision.