Compound · hcg
T1Hormone

HCG (Human Chorionic Gonadotropin)

Glycoprotein hormone that mimics luteinizing hormone at the LH/CG receptor on Leydig cells, stimulating endogenous testosterone production and maintaining intratesticular testosterone levels. Preserves testicular volume and spermatogenesis during exogenous androgen administration by bypassing hypothalamic-pituitary suppression.

Half-life
36 hours
Bioavailability
100% (SC/IM)
Route
subcutaneous, intramuscular
Evidence tier
T1 — Multiple RCTs
Optimization pillars
muscle · recovery
References
4 peer-reviewed
Dose ranges

Three tiers ordered by aggressiveness. Tier chips on every OPTIMIZE intervention let you filter the catalog by your evidence tolerance.

conservative
250 IU 2x/week
Fertility preservation on TRT
moderate
250–500 IU 3x/week
HPTA support during cycle
aggressive
1000–2000 IU 3x/week
PCT blast phase (limited duration)
Monitoring
  • total-testosterone
  • free-testosterone
  • estradiol
  • lh
  • fsh
  • hematocrit
  • prolactin
Contraindications
  • hormone-sensitive-cancer
  • precocious-puberty
  • uncontrolled-thyroid-disease
  • active-thromboembolism
References
  • PMID:15713727Preservation of fertility in patients with cancerN Engl J Med, 2005
  • PMID:19051804Human chorionic gonadotropin with testosterone for hypogonadism: an efficacy and safety studyJ Sex Med, 2009
  • PMID:23411532The effect of HCG on intratesticular testosterone in men receiving testosterone therapyFertil Steril, 2013
  • PMID:30056685Clomiphene citrate and hCG for fertility preservation in men on testosterone therapyCurr Urol Rep, 2018
Notes

HCG is not a performance compound. It is an insurance policy. Every man on exogenous testosterone is making a trade — gains now, fertility later. HCG changes the terms of that trade. 250IU three times per week keeps the Leydig cells firing. Skip it and you are gambling with a system that takes months to restart. The 36-hour half-life means every-other-day dosing maintains stable LH receptor activation without desensitization.

This is not medical advice

Discuss with a licensed clinician before starting, stopping, or changing any compound. This page documents what the research literature describes — it is not a prescription.

See HCG (Human Chorionic Gonadotropin) in a protocol matched to you

OPTIMIZE · a protocols.is product