HCG Overview
Mechanism of Action
Human Chorionic Gonadotropin is a glycoprotein hormone mimicking LH by binding to the LH/CG receptor. In males, it stimulates Leydig cells to produce testosterone, maintaining testicular function during TRT. In females, it supports ovulation induction and luteal phase support.
~24–36 hours
Timing
Morning or per protocol
Injection Site
Subcutaneous or intramuscular
Food
No restrictions
Common Stacks
- Testosterone replacement therapy
- Clomiphene — PCT protocol
HCG Dosing Protocol
TRT Support (Male)
Ongoing with TRT500–1000 IU 2–3x weekly
Concurrent with testosterone.
Fertility Protocol
Varies5000–10,000 IU per physician protocol
Per fertility specialist.
HCG Expected Timeline
Week 1–2
Increased testosterone production
Week 3–4
Improved testicular volume
Month 1–3
Sustained hormonal optimization
HCG Side Effects
Injection site pain
Gynecomastia (dose-dependent)
Water retention
Mood changes
HCG Research Studies
hCG stimulation of testicular testosterone production
Coviello AD, Matsumoto AM, Bremner WJ, et al. — J Clin Endocrinol Metab (2005)
Demonstrated hCG effectively stimulates intratesticular testosterone production, supporting fertility during exogenous testosterone therapy.
PubMed: 15870117HCG FAQ
Why is hCG used during TRT?
Exogenous testosterone suppresses LH via negative feedback, causing testicular atrophy and reduced sperm. hCG mimics LH, maintaining Leydig cell stimulation and preserving fertility.
Is hCG necessary for all TRT patients?
Not mandatory, but strongly recommended for men wanting to maintain fertility or prevent testicular atrophy.