Peptide Comparison
CetrorelixvsHuman Chorionic Gonadotropin (HCG)
Fast-acting GnRH antagonist that stops premature ovulation during IVF cycles
A powerful hormone that mimics luteinizing hormone (LH) to stimulate your body's natural testosterone production while keeping your fertility intact—like having your cake and eating it too for men on hormone therapy.
At a Glance
Quick
comparison
Dose Range
Cetrorelix
0.25 mg–3 mg mg
Human Chorionic Gonadotropin (HCG)
250–2000 IU
Frequency
Cetrorelix
Once daily
Human Chorionic Gonadotropin (HCG)
Twice weekly
Administration
Cetrorelix
Subcutaneous injection
Human Chorionic Gonadotropin (HCG)
Subcutaneous injection
Cycle Length
Cetrorelix
Ongoing/indefinite
Human Chorionic Gonadotropin (HCG)
Ongoing/indefinite
Onset Speed
Cetrorelix
Moderate (1-2 weeks)
Human Chorionic Gonadotropin (HCG)
Moderate (1-2 weeks)
Evidence Level
Cetrorelix
Strong human trials (Phase 3 or FDA approved)
Human Chorionic Gonadotropin (HCG)
Strong human trials (Phase 3 or FDA approved)
Efficacy
Benefit
ratings
Ovulation Control
Cycle Flexibility
Side Effect Profile
Fertility Preservation
Testicular Health
Hormone Balance
Technical Data
Compound
specifications
Cetrorelix
Molecular Formula
C70H92ClN17O14
Molecular Weight
1431.06 Da
Half-Life
Approximately 2-6 hours (varies by route of administration)
Bioavailability
~85% (subcutaneous injection)
CAS Number
100885-89-0
Human Chorionic Gonadotropin (HCG)
Molecular Formula
C1105H1770N318O336S26 (approximate)
Molecular Weight
36,700 g/mol (approximately)
Half-Life
24-36 hours
Bioavailability
High when injected subcutaneously or intramuscularly
CAS Number
9002-61-3
Protocols
Dosing
tiers
Cetrorelix
Human Chorionic Gonadotropin (HCG)
Applications
Best
suited for
Cetrorelix
Planning IVF with precise ovulation timing
Cetrorelix is particularly well-suited for individuals focused on planning ivf with precise ovulation timing. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Preventing premature egg release during controlled stimulation
Cetrorelix is particularly well-suited for individuals focused on preventing premature egg release during controlled stimulation. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Managing polycystic ovary syndrome (PCOS) during fertility treatment
Cetrorelix is particularly well-suited for individuals focused on managing polycystic ovary syndrome (pcos) during fertility treatment. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Human Chorionic Gonadotropin (HCG)
Fertility Preservation During TRT
If you're on testosterone therapy but want to keep your swimmers swimming, HCG is your best friend. It keeps your testes active and producing sperm even when external testosterone would normally shut that down. Research shows it can maintain or restore spermatogenesis in about 80% of men.
Preventing Testicular Atrophy
Nobody wants their boys to shrink. When you take external testosterone, your brain stops signaling your testes to work—and they get smaller from disuse. HCG mimics the signal (LH) that keeps them active, maintaining their size and function.
Hypogonadotropic Hypogonadism
If your pituitary gland isn't sending the right signals to your testes (low LH), HCG can step in and do the job. It's been used for decades to treat this condition, helping men achieve normal testosterone levels and fertility.
Post-Cycle Therapy (PCT)
After using anabolic steroids, your natural hormone production is suppressed. HCG can help jumpstart your testes back into action, speeding up the recovery of your natural testosterone production. It's often used as part of a comprehensive PCT protocol.
Safety Profile
Side
effects
Cetrorelix
Common
- Injection site reactions (redness, itching, swelling)
- Headache
- Nausea
- Mild abdominal discomfort
- Dizziness
- Allergic reactions (rash, difficulty breathing)
- Ovarian hyperstimulation syndrome (OHSS) if used with other fertility drugs
- Ovarian cysts
- Vaginal bleeding
- Mood changes
- Liver enzyme changes
- Pelvic pain
- Severe allergic reaction
Serious
- Severe allergic reaction
Human Chorionic Gonadotropin (HCG)
Common
- Injection site reactions
- Headache
- Water retention
Uncommon
- Gynecomastia
- Mood changes
- Acne
Serious
- Blood clots
Research Status
Safety
& evidence
Cetrorelix
Evidence Level
Strong human trials (Phase 3 or FDA approved)
FDA Status
FDA approved for this use
Safety Overview
Cetrorelix is an FDA-approved GnRH antagonist used exclusively in assisted reproductive technology with proven safety in short-term reproductive cycles. Unlike GnRH agonists, cetrorelix lacks the initial testosterone flare, making it well-tolerated for ovarian stimulation. Primary side effects are mild and local—injection site reactions (erythema, bruising) occur in 10-20% of patients. No systemic bone loss, cardiovascular complications, or serious adverse events have been reported in the reproductive context where treatment duration is limited (typically 7-10 days). The short treatment window in IVF protocols minimizes long-term safety concerns. Hypersensitivity reactions are rare but possible.
Contraindications
- xKnown allergy to cetrorelix or any ingredient
- xPregnancy (it may harm the developing baby)
- xUndiagnosed vaginal bleeding
- xSevere liver or kidney disease
- xLatex allergy (some syringes contain latex)
Human Chorionic Gonadotropin (HCG)
Evidence Level
Strong human trials (Phase 3 or FDA approved)
FDA Status
FDA approved for other use
Safety Overview
HCG has been used medically for over 80 years with a well-established safety profile. When used appropriately for male hypogonadism or fertility preservation, side effects are generally mild and manageable. The most common issues relate to elevated estrogen from increased testosterone aromatization, which can be managed with aromatase inhibitors if needed. Serious side effects are rare when HCG is used under medical supervision.
Contraindications
- xHormone-sensitive cancers (prostate, breast)
- xPrecocious puberty in children
- xKnown allergy to HCG or any component
- xPregnancy (in therapeutic male contexts)
- xUntreated thyroid or adrenal disorders
Decision Guide
Which is
right for you?
Choose Cetrorelix if...
- Planning IVF with precise ovulation timing
- Preventing premature egg release during controlled stimulation
- Managing polycystic ovary syndrome (PCOS) during fertility treatment
Choose Human Chorionic Gonadotropin (HCG) if...
- Fertility preservation during TRT
- Maintaining testicular size and function
- Natural testosterone stimulation
- Post-cycle therapy recovery