hCG vs Triptorelin

Glycoprotein hormone binding LH receptor on Leydig cells; stimulates testosterone production; prevents testicular atrophy during TRT; maintains spermatogenesis via FSH-like activity

Human chorionic gonadotropin (hCG) is a glycoprotein hormone that acts as a functional analogue of luteinizing hormone (LH), binding to LH receptors on Leydig cells in the testes and granulosa cells in the ovaries to stimulate steroidogenesis. In men, hCG stimulates testicular testosterone production directly, making it a widely used clinical tool for hypogonadotropic hypogonadism, male fertility support, and preservation of testicular function alongside testosterone replacement therapy. Clinical research demonstrates hCG effectiveness for improving testosterone levels and sperm parameters in males with gonadotropin deficiency, as well as for triggering final oocyte maturation in IVF protocols. hCG is an FDA-regulated biologic available in multiple approved formulations; use requires physician supervision due to dose-dependent effects on testosterone, estradiol, and reproductive signaling. hCG dosage in TRT support: in men using testosterone replacement therapy, hCG is prescribed to prevent testicular atrophy and maintain intratesticular testosterone levels needed for spermatogenesis. Typical clinical doses range from 250 to 500 IU subcutaneously administered 2–3 times per week, though protocols vary by provider and individual response. At higher doses, hCG's stimulation of testicular testosterone can also increase aromatization to estradiol — a clinically relevant consideration in TRT management requiring estrogen monitoring. hCG vs gonadorelin: both are used in men's health for testicular preservation alongside TRT, but they act at different axis levels. hCG acts directly on Leydig cell LH receptors, bypassing the pituitary entirely — a direct trophic signal to the testes. Gonadorelin acts upstream at the pituitary to stimulate endogenous LH and FSH release, preserving the full hypothalamic-pituitary-gonadal axis including FSH-driven spermatogenesis. For men prioritizing sperm production, gonadorelin's preservation of FSH signaling offers a potential advantage; for men primarily focused on testicular volume and intratesticular testosterone maintenance, hCG provides a well-validated, direct approach. Telehealth and men's health providers offering hCG and gonadorelin protocols are listed in the PeptideBase directory.

Potent GnRH agonist; single pulse stimulates LH/FSH surge and restores HPG axis after suppression (e.g., post-steroid cycle)

Triptorelin is a synthetic decapeptide GnRH agonist with a longer half-life than endogenous GnRH, used clinically to produce controlled hormonal suppression of the reproductive axis via receptor downregulation. Unlike the brief stimulatory effect of native GnRH, continuous or depot administration of triptorelin paradoxically desensitizes pituitary GnRH receptors, producing sustained suppression of LH, FSH, and sex hormone levels through a process known as medical castration. Clinical trials have established triptorelin efficacy for androgen deprivation therapy in prostate cancer, treatment of central precocious puberty, and hormonal management of endometriosis and uterine fibroids. Triptorelin is an FDA-approved prescription medication (Trelstar) available in depot formulations; it requires specialist-supervised monitoring due to an initial hormonal flare on commencement and the significant physiological effects of prolonged sex hormone suppression. Triptorelin for HPTA restart (PCT context) Outside its approved indications, triptorelin has been discussed in post-cycle therapy (PCT) and testosterone replacement therapy (TRT) restart contexts. The rationale is mechanistic: a single low dose of triptorelin triggers a brief, intense LH and FSH pulse before inducing pituitary downregulation — this initial agonist surge may be sufficient to re-sensitise a suppressed hypothalamic-pituitary-gonadal (HPG) axis following prolonged androgen administration that has blunted endogenous LH/FSH production. Some research and anecdotal literature describes single-dose triptorelin protocols (typically 100–200mcg administered once) as an HPTA restart approach, with the goal of re-initiating endogenous testosterone production. This use is not FDA-approved, not evaluated in randomised controlled trials for this indication, and not a standard of care in any guideline. It represents an off-label research and community-practice area. Triptorelin's mechanism — producing sustained hormonal suppression — means that incorrect dosing or repeated administration would achieve the opposite of the desired restart effect; this context requires qualified clinical supervision. PeptideBase does not endorse off-label use; this is informational context about how the compound is discussed in research and clinical community settings.