Skip to content
Winnowleaf home

Peptide

Gonadorelin (Factrel)

Gonadorelin is a synthetic decapeptide identical to endogenous GnRH. FDA-approved as diagnostic agent for evaluating pituitary gonadotrope function. Also used therapeutically for hypogonadotropic hypogonadism via pulsatile pump. In males with HH, pulsatile GnRH achieves spermatogenesis in 85% (58/68 patients). Earlier spermatogenesis vs gonadotropin therapy (6 vs 14 months, p=0.01).

Research notice. This page is for education and research. Peptides may not be FDA-approved for human use and may only be legally available for research. Talk to a qualified clinician before considering any peptide.

Best evidence
Grade A
Conditions studied
1
Outcomes
10
Graded outcomes
4051

Evidence by condition

  • Strong
  • Moderate
  • Limited
  • Very limited

1 condition, plus general outcomes

Hypogonadotropic Hypogonadism: outcomes studied for Gonadorelin (Factrel)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Puberty Induction

Pulsatile GnRH induces physiological puberty in HH. Advantages over testosterone: stimulates testicular growth and fertility while achieving virilization.

Improves (the measure goes up)Large effect82 studies

Studies that measured puberty induction

and 72 more in the citations list

Diagnostic Accuracy

GnRH stimulation test evaluates HPG axis. Measures LH/FSH response to bolus. Cannot distinguish CDP from IHH prepubertally, but useful post-pubertally.

Improves (the measure goes up)Moderate effect81 studies

Studies that measured diagnostic accuracy

and 71 more in the citations list

Spermatogenesis Induction

Pulsatile GnRH achieves spermatogenesis in 85% (58/68) of HH males. Median time 6 months with pump vs 14 months with gonadotropin therapy (p=0.01).

Improves (the measure goes up)Large effect81 studies

Studies that measured spermatogenesis induction

and 71 more in the citations list

Testicular Growth

100% of HH males treated with pulsatile GnRH achieve testicular growth and virilization. Physiological approach preserving fertility.

Improves (the measure goes up)Large effect81 studies

Studies that measured testicular growth

and 71 more in the citations list

General

General: outcomes studied for Gonadorelin (Factrel)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Reproductive Outcomes

21 preclinical studies support this finding. Primarily preclinical evidence.

Improves (the measure goes up)Moderate effect10 studies

Studies that measured reproductive outcomes

Immune Function

5 preclinical studies support this finding. Primarily preclinical evidence.

Improves (the measure goes up)Small effect6 studies
Hair Growth

4 preclinical studies support this finding. Primarily preclinical evidence.

Improves (the measure goes up)Small effect5 studies
Anti-Cancer Activity

3 preclinical studies support this finding. Primarily preclinical evidence.

Improves (the measure goes up)Small effect4 studies

Studies that measured anti-cancer activity

Hormone Levels

3 preclinical studies support this finding. Primarily preclinical evidence.

Improves (the measure goes up)Small effect4 studies
Safety/Tolerability

2 preclinical studies support this finding. Primarily preclinical evidence.

Improves (the measure goes up)Small effect3 studies

Key findings

  • Puberty InductionHypogonadotropic HypogonadismImproves (the measure goes up)
  • Diagnostic AccuracyHypogonadotropic HypogonadismImproves (the measure goes up)
  • Spermatogenesis InductionHypogonadotropic HypogonadismImproves (the measure goes up)

Studies cited

27 studies from PubMed

  1. Effects of gonadorelin on gonadotropin expression, plasma sex steroid concentrations and ovarian follicle dynamics in mature tambaqui (Colossoma macropomum).Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology, 2025 · PMID 40645558
  2. A biomimetic enzyme-linked immunosorbent assay (BELISA) for the analysis of gonadorelin by using molecularly imprinted polymer-coated microplates.Analytical and bioanalytical chemistry, 2022 · PMID 35028691
  3. The safety of neoadjuvant hormonal treatment in infants with cryptorchidism.Journal of pediatric urology, 2022 · PMID 35691791
  4. Gonadotropin Treatment for the Male Hypogonadotropic HypogonadismJ Clin Med, 2020 · PMID 32445446
  5. Impact of phase of the estrous cycle and season on LH surge profile and fertility in dairy cows treated with different GnRH analogs (gonadorelin vs. buserelin).Theriogenology, 2017 · PMID 28215676
  6. Role of Gonadotropin-releasing Hormone Stimulation Test in Diagnosing Gonadotropin Deficiency in Both Males and Females with Delayed PubertyJ Pediatr Endocrinol Metab, 2015 · PMID 26365959
  7. Effect of gonadorelin, lecirelin, and buserelin on LH surge, ovulation, and progesterone in cattle.Theriogenology, 2015 · PMID 25890780
  8. Effect of different gonadorelin (GnRH) products used for the first or resynchronized timed artificial insemination on pregnancy rates in postpartum dairy cows.Theriogenology, 2015 · PMID 25979657
  9. Raloxifene and antiestrogenic gonadorelin inhibits intestinal tumorigenesis by modulating immune cells and decreasing stem-like cells.Cancer prevention research (Philadelphia, Pa.), 2014 · PMID 24431404
  10. [Micropump infusion of gonadorelin in the treatment of hypogonadotropic hypogonadism in patients with pituitary stalk interruption syndrome: cases analysis and literature review].Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences, 2014 · PMID 25131486
  11. Comparison of gonadorelin products in lactating dairy cows: efficacy based on induction of ovulation of an accessory follicle and circulating luteinizing hormone profiles.Theriogenology, 2009 · PMID 19394072
  12. [Side effects of treatment with the long-acting gonadorelin agonist triptorelin in a case of paraphilia].Tijdschrift voor psychiatrie, 2007 · PMID 17290340
  13. [Ovulation inducing drugs].Journal de gynecologie, obstetrique et biologie de la reproduction, 2005 · PMID 16108118
  14. The effect of different doses of gonadorelin on ovarian follicle dynamics in river buffalo (Bubalus bubalis).Theriogenology, 2004 · PMID 15325555
  15. The effects of 3 gonadorelin products on luteinizing hormone release, ovulation, and follicular wave emergence in cattle.The Canadian veterinary journal = La revue veterinaire canadienne, 2003 · PMID 12650040
  16. If gonadotropin-releasing hormone plus growth hormone (GH) really improves growth outcomes in short non-GH-deficient children, then what?The Journal of clinical endocrinology and metabolism, 2001 · PMID 11443152
  17. [Research progress in immune regulation of gonadorelin].Sheng li ke xue jin zhan [Progress in physiology], 2000 · PMID 12545741
  18. Gonadorelin-induced testosterone release: a biological assay for quality assurance of gonadorelin in veterinary medicine.Drug development and industrial pharmacy, 1999 · PMID 10071824
  19. Response to gonadotrophin-releasing hormone by the intact male dog: serum testosterone, luteinizing hormone and follicle-stimulating hormone.Journal of reproduction and fertility. Supplement, 1993 · PMID 8229946
  20. GnRH analogues in reproductive medicine.The Medical journal of Australia, 1991 · PMID 2056937
  21. Gonadorelin for induction of ovulation.The Medical letter on drugs and therapeutics, 1990 · PMID 2196417
  22. [Treatment of cancer of the prostate. Role of gonadorelin analogs].Presse medicale (Paris, France : 1983), 1989 · PMID 2524792
  23. Immunoglobulin-mediated hypersensitivity in response to long-term treatment with gonadorelin hydrochloride (Factrel) in a female patient.American journal of obstetrics and gynecology, 1989 · PMID 2653043
  24. Application of gonadotropin releasing hormone in hypogonadotropic hypogonadism--diagnostic and therapeutic aspectsHorm Res, 1988 · PMID 15554892
  25. Ovulation induction with pulsatile intravenous GnRH.The Journal of reproductive medicine, 1985 · PMID 3908673
  26. [Treatment of advanced prostatic cancer with a gonadorelin agonist, dTrp6 LHRH. 41 cases].Presse medicale (Paris, France : 1983), 1985 · PMID 2934695
  27. The International Reference Preparation of Gonadorelin for Bioassay: a comparison with different preparations of synthetic luteinizing hormone releasing hormone using physicochemical methods of analysis, different bioassays and immunoassay.The Journal of endocrinology, 1982 · PMID 6752326