Peptides for Fertility (Male & Female)

Fertility struggles affect roughly 1 in 6 couples worldwide, and conventional treatments like IVF and hormone injections — while effective — come with real downsides. Ovarian hyperstimulation syndrome (OHSS), needle fatigue, emotional burnout, and costs that spiral past $20,000 per cycle drive many people to ask: is there a better way?

Peptide-based therapies are beginning to answer that question. Some, like kisspeptin, are already in clinical trials as ovulation triggers. Others, like gonadorelin, have decades of use behind them. And a few — growth hormone secretagogues and tissue-repair peptides — sit at earlier stages of research but offer intriguing possibilities for both egg and sperm quality.

This guide covers what the science actually says about peptides for fertility in both men and women — no vendor hype, no oversimplification.

How Peptides Fit Into Reproductive Biology
Kisspeptin: The Ovulation Trigger With a Safer Profile
Gonadorelin: Pulsatile GnRH Therapy for Both Sexes
GLP-1 Receptor Agonists and the "Ozempic Babies" Phenomenon
Growth Hormone Secretagogues: CJC-1295 and Ipamorelin
BPC-157: Tissue Repair and Reproductive Health
Comparison Table: Peptides for Fertility at a Glance
Emerging Peptide Research in Fertility
Safety and Regulatory Considerations
FAQ
The Bottom Line
References

How Peptides Fit Into Reproductive Biology

Your reproductive system runs on a signaling cascade that starts in the brain. The hypothalamus releases gonadotropin-releasing hormone (GnRH) in pulses. Those pulses tell the pituitary gland to produce luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In women, LH and FSH drive follicle development and ovulation. In men, they support testosterone production and sperm maturation.

When any link in this chain breaks down — stress shuts off GnRH pulses, obesity disrupts insulin signaling, age degrades egg or sperm quality — fertility suffers.

Peptides can intervene at multiple points in this cascade. Some stimulate GnRH release directly. Others boost growth hormone or reduce inflammation in reproductive tissues. The key advantage peptides offer over traditional hormone injections is specificity: because they target individual receptors, they can produce more physiological hormonal responses with fewer off-target effects [1].

Kisspeptin: The Ovulation Trigger With a Safer Profile

Kisspeptin sits at the very top of the reproductive hormone chain. It was discovered in 2003, when researchers found that people born without functioning kisspeptin receptors never went through puberty — their entire reproductive axis stayed dormant [2].

How It Works

Kisspeptin binds to KISS1R receptors on GnRH neurons in the hypothalamus, triggering the release of GnRH. That, in turn, stimulates LH and FSH secretion from the pituitary. Unlike injecting LH or FSH directly, kisspeptin works through the body's own signaling system, producing a more natural hormonal response.

Clinical Evidence for Women

The most advanced application is using kisspeptin-54 as an ovulation trigger during IVF — replacing the traditional human chorionic gonadotropin (hCG) injection that carries significant OHSS risk.

In a landmark study at Hammersmith Hospital in London, a single kisspeptin-54 injection triggered egg maturation in women undergoing IVF. Seventy-three healthy babies were born from the trial, and none of the women developed OHSS [3]. A follow-up phase 2 trial in 60 high-risk OHSS patients tested multiple doses (3.2 to 12.8 nmol/kg) and confirmed that kisspeptin safely triggered oocyte maturation across the dose range [4].

A next-generation kisspeptin receptor agonist called MVT-602 (TAK-448) has shown even more promise. In two 2024 randomized clinical trials, an intermediate dose of MVT-602 produced an LH surge that closely mirrored the body's natural midcycle pattern — something no current trigger agent achieves. Its effects lasted 21-22 hours compared to 4.7 hours for natural kisspeptin-54 [5].

Relevance for Men

Kisspeptin also stimulates LH release in men, making it a candidate for treating hypogonadotropic hypogonadism — a condition where the brain sends insufficient hormonal signals to the testes. Early research shows that kisspeptin administration can boost testosterone and, theoretically, support spermatogenesis in men whose infertility stems from central hormone deficiency [2].

Current Status

Kisspeptin-10 and kisspeptin-54 are not FDA-approved. Their use is limited to research settings and clinical trials. However, the evidence base is growing rapidly, and kisspeptin-based IVF protocols may reach clinical practice within the next few years.

Gonadorelin: Pulsatile GnRH Therapy for Both Sexes

Gonadorelin is a synthetic version of the body's own GnRH. Its fertility applications depend entirely on how it is delivered. Pulsed administration — mimicking the hypothalamus's natural rhythm — stimulates LH and FSH release. Continuous administration does the opposite: it shuts the system down.

Women: Functional Hypothalamic Amenorrhea

When stress, excessive exercise, or severe caloric restriction suppresses GnRH pulsatility, ovulation stops. This condition, functional hypothalamic amenorrhea (FHA), is one of the most responsive to pulsatile GnRH therapy.

A 25-year retrospective study of 66 women with FHA who received pulsatile GnRH pump therapy found ovulation rates between 75.6% and 85.2% per cycle, with live birth rates around 35% per cycle — numbers comparable to those of women who ovulate normally [6]. The therapy also avoids OHSS and significantly reduces the risk of multiple pregnancies, two major concerns with gonadotropin injections.

Men: Congenital Hypogonadotropic Hypogonadism

For men born with deficient GnRH signaling, pulsatile gonadorelin therapy can restart the entire reproductive axis. A comparative study found that pulsatile gonadorelin (10 mcg every 90 minutes) induced spermatogenesis earlier than traditional hCG/hMG injection therapy, with 61% of men achieving nearly normal development after one year and 88.5% after two years [7].

Availability Challenges

Pulsatile GnRH therapy is an established treatment in several European countries, including France, Germany, Austria, and the Netherlands. In the United States, it is not currently FDA-approved for fertility treatment, which limits access despite strong clinical evidence.

GLP-1 Receptor Agonists and the "Ozempic Babies" Phenomenon

The connection between semaglutide and fertility caught the public by surprise. Women who had struggled to conceive for years were getting pregnant — sometimes unexpectedly — after starting GLP-1 medications for weight loss or diabetes.

The PCOS Connection

Polycystic ovary syndrome (PCOS) affects 6-20% of women of childbearing age and is one of the leading causes of anovulatory infertility. Excess body weight drives insulin resistance, which increases ovarian androgen production, which disrupts ovulation. It is a vicious cycle.

GLP-1 receptor agonists break this cycle primarily through weight loss. Losing just 5-10% of body weight can restore ovulation in many women with PCOS [8]. But the effects may go beyond weight loss alone. Studies show that women with PCOS who use GLP-1 receptor agonists experience greater improvements in menstrual regularity and ovulation rates compared to lifestyle changes alone, even when controlling for weight loss [9].

Direct Reproductive Effects

GLP-1 receptors are found in the hypothalamus, pituitary, and ovaries, raising the possibility of direct reproductive effects. Research shows GLP-1 receptor agonists reduce circulating insulin and testosterone levels in women with PCOS — both of which independently improve ovulatory function [9].

Critical Safety Warnings

GLP-1 medications are not fertility treatments. Manufacturers recommend stopping semaglutide at least two months before attempting to conceive. Animal studies have shown adverse fetal effects including miscarriages and structural abnormalities [10]. GLP-1 drugs also slow gastric emptying, which can reduce the effectiveness of oral birth control — a factor that may partly explain some unplanned "Ozempic babies."

Growth Hormone Secretagogues: CJC-1295 and Ipamorelin

Growth hormone (GH) plays a documented role in reproductive function that is often overlooked. GH receptors are present in the ovaries and testes. GH-deficient men have smaller testes and impaired sperm production. GH-deficient women show reduced follicular response during IVF [11].

How CJC-1295 and Ipamorelin Work

CJC-1295 is a long-acting GHRH analog that stimulates the pituitary to release growth hormone. A single injection can elevate GH levels 2- to 10-fold for up to six days and IGF-1 levels for 9-11 days [12]. Ipamorelin is a selective growth hormone-releasing peptide that works through a different receptor (the ghrelin receptor) but produces complementary GH elevation with minimal side effects.

Relevance to Male Fertility

Growth hormone acts directly at the testicular level to promote sperm development. GH supports early spermatogonia development and complete sperm maturation. In GH-deficient men, GH replacement therapy has been shown to restore sperm concentration, morphology, and motility [11]. When used as adjunct therapy, GH has induced spermatogenesis in men with hypogonadotropic hypogonadism who did not respond to gonadotropin therapy alone.

CJC-1295 and ipamorelin stimulate the body's own GH production rather than replacing it with exogenous GH. This preserves the pulsatile pattern of GH release that appears important for testicular function.

Relevance to Female Fertility

IGF-1, which rises with GH secretagogue use, plays a documented role in follicular development and ovulation. Research in animal models shows that GH levels rise significantly around ovulation, and exogenous GH secretagogues can support appropriate ovulation timing [13].

In IVF settings, GH supplementation has been studied as an adjunct for poor responders — women whose ovaries produce few eggs despite aggressive stimulation. While results are mixed, some studies show improved egg numbers and quality.

Evidence Gap

Direct clinical trials of CJC-1295 or ipamorelin for fertility outcomes do not exist. The rationale is built on well-established GH/fertility science plus the pharmacology of these peptides. This is an area where the theory is strong but the specific clinical data lags behind.

BPC-157: Tissue Repair and Reproductive Health

BPC-157 is a 15-amino-acid peptide derived from human gastric juice, studied extensively for tissue repair, anti-inflammatory effects, and gut healing. Its connection to fertility is indirect but scientifically interesting.

Theoretical Mechanisms

BPC-157 promotes angiogenesis (new blood vessel formation) and accelerates tissue repair in nearly every tissue studied — gut, tendon, muscle, bone, and nerve [14]. These same mechanisms could theoretically benefit reproductive tissues:

Endometrial repair: Women with thin endometrial lining or scarring from prior procedures may benefit from BPC-157's tissue-repair properties, though this has not been studied in humans.
Testicular protection: Animal studies show BPC-157 protects against testicular damage from toxins and oxidative stress, suggesting a protective role for male fertility [15].
Inflammation reduction: Chronic pelvic inflammation damages both male and female reproductive tissues. BPC-157's potent anti-inflammatory effects could theoretically reduce this damage.

What the Research Does Not Show

No human clinical trials have tested BPC-157 for any reproductive health outcome. Reproductive toxicity, teratogenicity, and effects on estrogen, progesterone, or menstrual cycles remain completely unstudied. The theoretical case is reasonable; the evidence to support clinical use does not yet exist.

Comparison Table: Peptides for Fertility at a Glance

Peptide	Primary Mechanism	Female Application	Male Application	Evidence Level	Regulatory Status
Kisspeptin	Triggers GnRH release	IVF ovulation trigger; reduced OHSS risk	Hypogonadotropic hypogonadism	Phase 2 clinical trials	Investigational
Gonadorelin	Synthetic GnRH; pulsatile delivery	Hypothalamic amenorrhea; ovulation induction	Congenital hypogonadotropic hypogonadism	25+ years of clinical data	Approved in some EU countries; limited in US
Semaglutide	GLP-1 receptor agonist; weight/insulin effects	PCOS-related anovulation (via weight loss)	Testosterone improvement (via weight loss)	Observational + RCTs for metabolic endpoints	FDA-approved for diabetes/weight loss; not fertility
CJC-1295	GHRH analog; boosts GH/IGF-1	Adjunct for poor IVF responders (theoretical)	Sperm quality via GH pathway	Preclinical + GH fertility studies	Investigational
Ipamorelin	GH secretagogue via ghrelin receptor	Similar to CJC-1295	Similar to CJC-1295	Preclinical + GH fertility studies	Investigational
BPC-157	Tissue repair; anti-inflammatory	Endometrial repair (theoretical)	Testicular protection (animal data)	Preclinical only	Not approved

Emerging Peptide Research in Fertility

Several peptides at earlier research stages deserve mention:

AMH Peptide Mimics

Cleveland Clinic researchers are developing AMHR2BP, a peptide that mimics anti-Mullerian hormone (AMH). Its primary application is fertility preservation for women undergoing chemotherapy, where it may protect ovarian follicles from drug-induced destruction [16]. It could also potentially slow age-related loss of ovarian reserve.

Fertilin-Derived Peptide (cFEE)

A cyclic peptide derived from the fertilin protein has been shown to improve human oocyte maturation in vitro and reduce chromosomal abnormalities (aneuploidy). This has direct implications for IVF success rates and fertility preservation [17].

Seminal Peptides

Researchers have identified novel peptides in seminal fluid — including RSIY-15 and SSIY-15 — that improve sperm motility when added to semen samples. These semenogelin-derived peptides inhibit neutral endopeptidase (NEP), an enzyme that affects sperm movement patterns. This line of research could lead to improved sperm preparation techniques for assisted reproduction [18].

Safety and Regulatory Considerations

A few points that apply across all peptides discussed here:

No peptide in this article is FDA-approved as a fertility treatment. Kisspeptin and gonadorelin are the closest to clinical use, with active clinical trials. Others remain in earlier research phases.

Timing matters. Any peptide that affects hormones should be coordinated with fertility treatment protocols. Self-administering peptides without medical oversight can interfere with IVF stimulation, ovulation timing, or hormonal monitoring.

Pregnancy exposure data is minimal. For most of these peptides, we do not know whether they are safe during early pregnancy. The conservative approach — stopping peptide use before conception — applies until better data exists.

Quality and purity concerns are real. Research peptides obtained outside of clinical trials may contain impurities, incorrect doses, or degradation products. This is a meaningful risk when reproductive outcomes are at stake.

If you are interested in peptide-based fertility support, the safest path is working with a reproductive endocrinologist who is familiar with the current research. For a broader view of how peptides interact with reproductive hormones, see our guides on peptides for hormonal balance in women, peptides for men over 40, peptides for testosterone support, and peptides for perimenopause and menopause.

FAQ

Which peptide has the strongest evidence for fertility? Kisspeptin has the most direct clinical trial evidence as a fertility treatment. Phase 2 trials have demonstrated its effectiveness as an IVF ovulation trigger with significantly lower OHSS risk than standard hCG. Gonadorelin (pulsatile GnRH) has even longer clinical history for specific conditions like hypothalamic amenorrhea and male hypogonadotropic hypogonadism.

Can semaglutide or Ozempic help with PCOS-related infertility? GLP-1 medications can restore ovulation in some women with PCOS, primarily through weight loss and improved insulin sensitivity. However, they are not fertility drugs. You must stop semaglutide at least two months before trying to conceive due to potential fetal risks. Work with your doctor on timing.

Do growth hormone peptides like CJC-1295 improve sperm quality? The rationale is sound — growth hormone has documented roles in sperm development, and CJC-1295 reliably increases GH levels. However, no clinical trials have directly tested CJC-1295 for male fertility outcomes. The evidence is extrapolated from GH replacement studies.

Is BPC-157 safe to take while trying to conceive? There is no safety data for BPC-157 during conception or early pregnancy. Its effects on reproductive hormones, egg quality, sperm quality, and embryo development have not been studied in humans. The lack of data does not mean it is dangerous — it means we genuinely do not know.

How does kisspeptin compare to hCG as an IVF trigger? Kisspeptin produces a more physiological LH surge and carries dramatically lower OHSS risk. Pregnancy rates in trials (23-37%) are comparable to standard protocols. The main limitation is that kisspeptin is still investigational and not yet available outside clinical trials.

Can peptides replace IVF or other fertility treatments? No. Peptides are being studied as components of fertility treatment — better ovulation triggers, safer protocols, improved egg or sperm quality. They do not bypass the need for medical fertility evaluation and treatment.

The Bottom Line

The peptide fertility field splits into two categories. On one side, kisspeptin and gonadorelin have real clinical evidence and are moving toward broader use — kisspeptin as a safer IVF trigger, gonadorelin as an established therapy for specific hormonal deficiencies. On the other side, growth hormone secretagogues and tissue-repair peptides like BPC-157 offer compelling biological rationale but lack the clinical trials needed to confirm their reproductive benefits.

What is clear is that the one-size-fits-all approach to fertility treatment is giving way to something more precise. Peptides that work through the body's own signaling systems — rather than overriding them with supraphysiological hormone doses — represent a meaningful shift in how we think about reproductive medicine.

For anyone navigating fertility challenges, the most useful takeaway is this: talk to a reproductive endocrinologist about the latest research. The field is moving fast, and peptide-based options that were experimental two years ago may be available in clinical trials today.

References

Sikiric, P., et al. (2025). "Peptide Therapies Poised to Transform Fertility Treatment: Advances, Challenges, and Future Prospects." Inovi Fertility and Genetics Institute. Link
Pinilla, L., et al. (2012). "Kisspeptin: Role in reproduction and implications for infertility management." Indian Journal of Endocrinology and Metabolism, 16(Suppl 3), S413-S421. PMC3493843
Jayasena, C.N., et al. (2014). "Kisspeptin-54 triggers egg maturation in women undergoing in vitro fertilization." Journal of Clinical Investigation, 124(8), 3667-3677. PMC4109525
Abbara, A., et al. (2015). "Efficacy of Kisspeptin-54 to Trigger Oocyte Maturation in Women at High Risk of OHSS During IVF Therapy." Journal of Clinical Endocrinology & Metabolism, 100(9), 3322-3331. PMC4570165
MacLean, D.B., et al. (2024). "Kisspeptin and neurokinin B: roles in reproductive health." Physiological Reviews. Link
Martin, B., et al. (2022). "Use of pulsatile gonadotropin-releasing hormone (GnRH) in patients with functional hypothalamic amenorrhea (FHA) results in monofollicular ovulation and high cumulative live birth rates: a 25-year cohort." Journal of Assisted Reproduction and Genetics. Link
Zhang, L., et al. (2019). "The Pulsatile Gonadorelin Pump Induces Earlier Spermatogenesis Than Cyclical Gonadotropin Therapy in Congenital Hypogonadotropic Hypogonadism Men." American Journal of Men's Health, 13(1). PMC6775549
University Hospitals. (2025). "How GLP-1 Drugs Can Affect Fertility and Birth Control." Link
Salamun, V., et al. (2020). "Obesity, Polycystic Ovary Syndrome, and Infertility: A New Avenue for GLP-1 Receptor Agonists." Biomolecules, 10(8), 1134. PMC7457958
San Diego Fertility Center. (2024). "Ozempic and Fertility." Link
Calogero, A.E., et al. (2011). "Growth hormone in male infertility." International Journal of Endocrinology. PMC3183524
Teichman, S.L., et al. (2006). "Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog." Journal of Clinical Endocrinology & Metabolism, 91(3), 799-805. PubMed
Inovi Fertility. (2025). "CJC-1295 + Ipamorelin: Fertility Hormone Regulation, Benefits & Safety." Link
Sikiric, P., et al. (2016). "Brain-gut Axis and Pentadecapeptide BPC 157: Theoretical and Practical Implications." Current Neuropharmacology, 14(8), 857-865. PMC5333585
Inovi Fertility. (2025). "BPC-157 and Female Fertility: Effects, Mechanisms, Safety and Risks." Link
Cleveland Clinic. (2024). "AMH Peptide Mimic May Hold Key to Fertility Preservation in Chemotherapy Patients." Link
Bhatt, T., et al. (2021). "A fertilin-derived peptide improves in vitro maturation and ploidy of human oocytes." Fertility Science and Research. Link
Panner Selvam, M.K., et al. (2019). "Identification of two novel seminal peptides, which act as neutral endopeptidase inhibitors and modulate sperm motility." Fertility and Sterility. Link

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