Male Fertility Supplements: What May Help and What They Cannot Replace
Key Takeaways
Some trials report small changes in semen measures such as motility, but current evidence does not show that male fertility supplements improve live birth. They cannot diagnose or treat a varicocele, hormonal disorder, obstruction, or genetic cause, and they should not delay evaluation of both partners.
Key evidence: AUA/ASRM Guideline: Male Infertility Updates (2024) WHO Guideline on Infertility (2025) Systematic review of 50 randomised trials (2025)
An abnormal semen analysis can make a fertility supplement seem like an easy next step. Some studies report improvements in sperm movement or other measurements, but supplements have not been shown reliably to increase the chance of having a baby (2025 systematic review).
Before choosing a product, it helps to understand the result and whether either partner needs further assessment. A supplement cannot identify the cause of an abnormal test.
Why are antioxidants studied?
There is a plausible reason to study antioxidants. Sperm membranes contain fats that are vulnerable to oxidation, and sperm cells have limited capacity to repair damage.
Reactive oxygen species (ROS) also have normal signalling roles. Problems may arise when ROS production and antioxidant defences fall out of balance. Smoking, obesity, genital-tract inflammation and some environmental exposures are associated with this imbalance and with poorer sperm function, but a routine ROS test is not recommended in standard evaluation (EAU guideline).
Antioxidants are studied because they might restore that balance. The mechanism is reasonable; clinical benefit is still uncertain. A change in a semen result is not the same as a higher chance of pregnancy or live birth.
What do the guidelines say?
The guidelines express the uncertainty in different ways:
- AUA / ASRM Guidelines (2024): The joint AUA/ASRM Male Infertility Guideline characterises the use of antioxidants as having questionable clinical utility. The panel notes that available data are insufficient to recommend any specific supplement formulation or dose to improve live birth rates.
- European Association of Urology (EAU 2026): The EAU Male Infertility Guidelines advise against routinely treating idiopathic male infertility with antioxidants. This is a weak recommendation, reflecting the uncertainty of the evidence. The EAU also advises against routine seminal ROS testing in standard clinical evaluation.
- World Health Organization (WHO 2025): In its comprehensive guideline for the prevention, diagnosis and treatment of infertility, the WHO concluded that clinical trial evidence remains insufficient to form a recommendation either for or against antioxidant therapy in men with abnormal semen parameters.
The 2022 Cochrane review found a possible increase in live birth, but the evidence for that outcome was of very low certainty. When studies at high risk of bias were excluded, there was no evidence of an increased live-birth rate. This is uncertainty about benefit, rather than proof that every antioxidant is ineffective.
What is known about common ingredients?
Not all ingredients have been studied equally. A 2025 systematic review of 50 randomised trials found no convincing improvement in pregnancy or live birth with dietary supplements. Some ingredients changed individual semen parameters, but certainty was generally low or very low.
1. Coenzyme Q10 (CoQ10)
CoQ10 helps mitochondria produce energy and also acts as an antioxidant. Trials in men with unexplained infertility have reported small improvements in some semen measures, particularly motility. Doses and treatment periods varied, and no regimen has been shown to improve live birth reliably (2025 systematic review). These study protocols are not a personal dosing recommendation.
2. L-Carnitine and Acetyl-L-Carnitine
Carnitines are involved in sperm energy metabolism. Some trials report better motility, but broader evidence reviews have not shown that this translates into more pregnancies or live births.
3. Zinc and Folic Acid (The FAZST Trial)
Zinc and folate have normal roles in cell function, but adding them does not necessarily improve fertility. In the FAZST trial, 2,370 couples undergoing infertility treatment were studied. Men received either 30 mg of elemental zinc plus 5 mg of folic acid daily for six months, or placebo.
The supplement group did not have significantly better semen results or live-birth rates, and gastrointestinal symptoms were more frequent. These were research doses, not a recommendation for personal use.
4. Vitamins C and E
Vitamins C and E are often included in combination products because of their antioxidant roles. Trials use different mixtures and doses, making the effect of either vitamin difficult to isolate. There is no convincing evidence that either improves live birth (2025 review).
5. N-Acetyl Cysteine (NAC) and Selenium
NAC contributes to glutathione production, while selenium is involved in antioxidant enzymes. Some trials found changes in motility with selenium, but evidence for pregnancy and live birth remains uncertain. Combination products make it especially hard to know which ingredient, if any, is responsible (2025 review).
Can taking more cause harm?
More is not automatically better. Sperm need small amounts of ROS for normal signalling, including the changes that prepare a sperm cell to fertilise an egg.
Too much antioxidant exposure may push this balance towards reductive stress. This is a possible mechanism discussed in a narrative review, not proof that usual supplement use causes infertility. There is no validated “ideal” antioxidant dose (WHO guideline; 2025 review). If supplements are considered, a clinician or pharmacist should review the full ingredient list, overlapping products, medicines and medical conditions. Avoid commercial “stacks” and do not treat trial doses as prescriptions.
What does a fertility assessment add?
A medical history, examination and semen testing may identify a cause that needs specific care. Depending on the findings, hormone or other tests may be appropriate. Assessment does not always find an explanation; its purpose is to guide the next step for both partners (EAU guideline).
Dr. Aksoy’s approach
Dr. Aksoy may discuss a supplement trial of no more than three months, alongside lifestyle changes, when the semen abnormality is isolated and mild. His other conditions are a young female partner, suitable ovarian reserve and tubal findings, a short duration of infertility and no severe male factor. This is his approach to selected cases, not a routine guideline recommendation or a promise of benefit.
He prioritises assessment and treatment planning when the female partner is older, particularly beyond roughly 35–38, ovarian reserve is limited, infertility has lasted longer, or semen results show severe combined abnormalities or no sperm. That age range is a clinical consideration, not a cut-off below which waiting is always appropriate.
The next step may involve intrauterine insemination (IUI), IVF or ICSI, depending on the couple’s findings. These options are not interchangeable; azoospermia, for example, requires assessment of its cause and whether sperm can be obtained before choosing a treatment.
He makes this decision without routine oxidative-stress testing. The EAU guideline also advises against routine seminal ROS testing: evidence is insufficient to show that using these results to guide care reliably improves live birth.
When Not to Wait for an Evaluation
Do not spend several months trying supplements first if any of the following applies. A fertility clinician can evaluate both partners in parallel, and a reproductive urologist can assess male-specific findings.
- Conception has not occurred after 12 months of regular unprotected intercourse (or 6 months if the female partner is 35 or older), as set out in ASRM’s fertility-evaluation guidance.
- An initial semen analysis indicates significant abnormalities (such as severe oligozoospermia, asthenozoospermia, teratozoospermia, or azoospermia).
- There is a personal history of cryptorchidism (undescended testicle), testicular trauma, mumps orchitis, or previous inguinal/scrotal surgery.
- Physical examination reveals a palpable scrotal mass or suspected clinical varicocele (see our guide on varicocele repair vs IVF/ICSI).
- The patient uses medications known to impair spermatogenesis, such as exogenous testosterone or anabolic steroids.
The appropriate treatment depends on the cause, both partners’ findings and their priorities. Our guide to male infertility and IVF/ICSI explains where assisted reproduction may fit.
Related Reading
- Male Infertility and IVF: When IVF Helps and What It Does Not Solve
- Varicocele Repair vs IVF/ICSI: When to Consider Repair
- Improving Sperm Quality: What Actually Helps?
- Mobile Phones and Male Fertility: What the Evidence Shows
FAQ
When should an abnormal semen analysis be repeated?
The EAU guideline recommends at least two semen analyses if the first result is abnormal. Follow the laboratory’s collection instructions and agree the timing with your clinician. A three-month supplement trial is not a reason to postpone confirmation of an abnormal result.
Should we wait six or twelve months before asking for help?
Those are usual assessment timelines when there is no known reason to investigate earlier: twelve months without conception, or six months if the female partner is 35 or older. An abnormal semen result or another known risk factor warrants earlier assessment (ASRM guidance). They are not recommended periods for trying supplements first.
What should I bring to discuss supplements at my appointment?
Bring your semen results and a list or photographs of every supplement and medicine you take, including the daily doses. This helps your clinician or pharmacist check for repeated ingredients and interactions. Also discuss how long you have been trying to conceive and any fertility tests either partner has already had.
Sources
- American Urological Association and American Society for Reproductive Medicine. Updates to Male Infertility: AUA/ASRM Guideline (2024). J Urol. 2024;212(6):789–799. doi:10.1097/JU.0000000000004180.
- European Association of Urology. EAU Guidelines on Sexual and Reproductive Health — Male Infertility (2026).
- World Health Organization. Guideline for the prevention, diagnosis and treatment of infertility (2025). Geneva: World Health Organization; 2025.
- de Ligny W, et al. Antioxidants for male subfertility. Cochrane Database of Systematic Reviews. 2022;(5):CD007411. doi:10.1002/14651858.CD007411.pub5. PubMed.
- Schisterman EF, et al. Effect of Folic Acid and Zinc Supplementation in Men on Semen Quality and Live Birth Among Couples Undergoing Infertility Treatment: A Randomized Clinical Trial. JAMA. 2020;323(1):35-48. doi:10.1001/jama.2019.18714. PubMed.
- Michaelsen MP, et al. The Effect of Dietary Supplements on Male Infertility in Terms of Pregnancy, Live Birth, and Sperm Parameters: A Systematic Review and Meta-Analysis. Nutrients. 2025;17(10):1710. doi:10.3390/nu17101710. PubMed.
- Moustakli E, et al. Reductive stress and the role of antioxidants in male infertility: a narrative review. Archives of Gynecology and Obstetrics. 2025;312(5):1503–1514. doi:10.1007/s00404-025-08184-3. PubMed.
- Practice Committee of the American Society for Reproductive Medicine. Fertility evaluation of infertile women: a committee opinion (2021). Fertility and Sterility. 2021;116:1255–1265.
Add as a Preferred Source on Google
You can add draksoyivf.com as one of your preferred health information sources on Google.
The content has been created by Dr. Senai Aksoy and medically approved.