HCG
Human Chorionic Gonadotropin | LH Receptor Agonist
HCG is a glycoprotein hormone naturally produced by the placenta during pregnancy that binds LH receptors to stimulate testosterone and estrogen biosynthesis. FDA-approved for cryptorchidism, hypogonadotropic hypogonadism, and ovulation induction.
Mechanism of Action
Binds to LH receptors on Leydig cells in testes, stimulating testosterone production with a half-life of 24-36 hours, peak levels 6-12 hours post-injection, and 40-50% bioavailability via SubQ or IM routes.
Key Benefits
- Maintains testicular function during TRT
- Preserves fertility and prevents testicular atrophy
- Stimulates endogenous testosterone production
- Induces ovulation in women
- FDA-approved for multiple indications
- Well-established safety profile
Male Fertility
- TRT Adjunct
Maintains intratesticular testosterone at baseline during testosterone therapy, preventing atrophy and preserving fertility.
- Hypogonadotropic Hypogonadism
FDA-approved for secondary hypogonadism; combined with FSH for spermatogenesis induction.
- Post-Cycle Therapy
Restores testicular function after anabolic steroid cycles.
Female Fertility
- Ovulation Induction
FDA-approved trigger for follicular maturation; 15-25% pregnancy rate per cycle.
Pediatric
- Cryptorchidism
FDA-approved for prepubertal undescended testes not due to anatomical obstruction; ~25% success rate.
Subcutaneous or intramuscular injection. Administer 2-3 times weekly, evenly spaced. For TRT, many inject HCG on days between testosterone injections.
| Goal | Dose | Frequency | Route |
|---|---|---|---|
| TRT Adjunct (Low) | 250-500 IU | Every other day | SubQ/IM |
| TRT Adjunct (Standard) | 500-1000 IU | Twice weekly | SubQ/IM |
| HCG Monotherapy | 1500-2000 IU | 2-3x weekly | IM |
| Fertility (with FSH) | 1500-2000 IU | 2-3x weekly | IM |
| Cryptorchidism (Pediatric) | 1000-5000 IU | 2-3x weekly for 3-4 weeks | IM |
| Ovulation Trigger (Female) | 5000-10,000 IU | Single dose | IM/SubQ |
| PCT Protocol | 1000-1500 IU | Every other day for 2-3 weeks | SubQ/IM |
Reconstitution Instructions
- HCG lyophilized powder vial (typically 5000 or 10,000 IU)
- Bacteriostatic water or sodium chloride diluent (provided)
- Insulin syringes (29-31 gauge for SubQ)
- Alcohol prep pads
- 1 Remove vial and diluent from packaging
- 2 Clean rubber stoppers with alcohol swabs
- 3 Draw diluent into syringe (typically 1-2mL provided)
- 4 Slowly inject diluent into HCG vial, aiming at vial wall
- 5 Gently swirl to dissolve - do not shake vigorously
- 6 Allow to sit until completely dissolved and clear
- 7 Calculate concentration (e.g., 5000 IU in 2mL = 2500 IU/mL)
- 8 Label with reconstitution date and concentration
- 9 Store reconstituted HCG at 2-8°C
- 10 Use within 30-60 days
Commonly combined in TRT to maintain testicular function and preserve fertility.
Use sequentially; both affect HPG axis.
Commonly combined; HCG increases intratesticular aromatase activity.
Monitor combination effects on gonadotropin axis.
Synergistic for fertility; 70-90% spermatogenesis induction rate.
Complementary mechanisms for HPG axis stimulation.
HCG has weak TSH-like activity; monitor thyroid function.
Protective combination for metabolic health.
Cellular-level action begins; no immediate noticeable effects
Testosterone increase detectable on labs; possible mood/energy improvement
Testicular fullness/size improvement noticeable; improved well-being
Stable testosterone levels; fertility parameters beginning to improve
Sperm count improvements if used for fertility; sustained testicular function
Maintained testicular size and function with ongoing use
Common Side Effects
- Gynecomastia (breast tenderness/swelling) due to increased estrogen
- Headaches, irritability, and mood swings (especially initially)
- Fluid retention and edema
- Potential antibody formation with long-term use
Stop Signs - Discontinue if:
- Signs of gynecomastia (breast tenderness, swelling, nipple sensitivity)
- Severe or persistent headaches
- Signs of blood clots (leg swelling/pain, shortness of breath, chest pain)
- Allergic reactions (rash, hives, difficulty breathing, facial swelling)
- Severe abdominal pain or bloating in women (possible OHSS)
- Testicular pain or swelling beyond normal
- Significant mood changes (depression, aggression, severe irritability)
- Vision changes
Contraindications
- Hormone-sensitive cancers (prostate, breast)
- Pregnancy (except as prescribed)
- Precocious puberty risk in children
Good Signs
- White to off-white lyophilized powder or cake in sealed vial
- Completely clear solution after reconstitution
- Proper labeling: Pregnyl, Novarel (urinary), Ovidrel (recombinant)
- Clear expiration and lot number
- Cold chain compliance (recombinant requires refrigeration throughout)
Warning Signs
- Generic/compounding pharmacy products - quality varies
- Ensure compounding pharmacy is accredited
Bad Signs
- Cloudiness, discoloration, or floating particles indicates degradation
- Compromised vial seal or expired product
- HCG for Intratesticular Testosterone Maintenance(2005)
250 IU HCG every other day during TRT maintains intratesticular testosterone at baseline, preventing atrophy and preserving fertility.
- HCG Monotherapy for Hypogonadism(2013)
HCG monotherapy (1500-2000 IU twice weekly) effectively increased testosterone and improved symptoms while maintaining fertility.
- Spermatogenesis Induction with HCG/FSH(2018)
Combined HCG and FSH therapy induces spermatogenesis in 70-90% of men with hypogonadotropic hypogonadism.
- Cryptorchidism Treatment Meta-Analysis (Cochrane)(2014)
Meta-analysis of 1,231 boys showing ~25% success rate for hormonal treatment of cryptorchidism.
- Ovulation Induction Success Rates(2017)
HCG trigger achieves pregnancy rates of 15-25% per cycle in clomiphene/letrozole protocols.
Disclaimer
This information is for educational and research purposes only. Consult a healthcare professional before use.