Male Fertility Supplements: Do They Work? 50-Trial Review

This article is part of our Male Fertility: The Complete Guide.

Affiliate disclosure: we may earn a commission from links on this page at no extra cost to you. This does not change what we write.

By Healthy Supplements Editorial Team

Every shelf of male fertility supplements promises the same thing, and every couple trying to conceive asks the same question: do male fertility supplements work, or are they an expensive way to feel like you are doing something?

In May 2025 the journal Nutrients published the biggest attempt so far to answer that properly for male fertility supplements. We opened it and checked every figure below against the paper itself.

What the 2025 review actually did

The authors searched PubMed, Embase and CENTRAL from inception to May 2024. They kept only randomized controlled trials lasting twelve weeks or longer that compared male fertility supplements against placebo in male infertility. Of 3,137 articles identified, 50 were included (see the full record in Europe PMC).

Two primary outcomes were set in advance: pregnancy and live birth. Everything else, including sperm concentration, sperm count, total and progressive motility, normal morphology and the DNA Fragmentation Index, was secondary. Risk of bias used the Cochrane RoB2 tool and certainty of evidence used GRADE.

That design is why this paper answers the question do male fertility supplements work better than a single trial can. It asks about the baby, not only about the lab report.

The headline result

No effect on pregnancy and live birth was found. The authors conclude in their own words that the study found no convincing evidence of an effect of any dietary supplements on male infertility, and call for larger, better-conducted trials that consider pregnancy outcomes.

They also report that the majority of studies had some concerns or a high risk of bias, and that certainty of evidence was generally low or very low. So the answer to do male fertility supplements work is not merely negative; the underlying evidence is also thin.

See the Fertility Factor 5 label

Where single sperm measures moved

The review did find that some male fertility supplements moved individual sperm parameters. This is the part that pages selling male fertility supplements quote, so here it is in full, with nothing added.

Notice the shape of that table. Every row that moved, moved on a measurement. No row moved on a pregnancy.

Why better motility is not a baby

Sperm parameters are surrogate markers. They are easy to measure and they respond to things that do not necessarily change whether a couple conceives, which is exactly why the question do male fertility supplements work has to be asked at the outcome level.

An independent source makes the same point. The NIH Office of Dietary Supplements fact sheet on carnitine reports a meta-analysis of three trials (201 men, 1 to 3 grams a day for two to six months) in which carnitine improved sperm motility and morphology but not concentration, and a 2022 Cochrane review of six trials in which carnitine increased motility and concentration at some timepoints yet did not affect rates of live birth or pregnancy.

Two separate bodies of evidence, same split: the lab number can improve while the outcome does not.

Male fertility supplements: doses and safety ceilings

If you already take male fertility supplements, the useful question is no longer only do male fertility supplements work but whether your dose is sane. The official figures:

What goes wrong above those ceilings is documented. Zinc at 50 mg or more for several weeks can interfere with copper absorption and lower copper status. Chronic excess selenium causes selenosis, where hair loss and brittle or lost nails are often the first signs. Carnitine near 3 grams a day can cause nausea, cramps, diarrhoea and a fishy body odour.

On omega-3, the ODS fact sheet notes that FDA advises labels not recommend more than 2 grams a day of EPA plus DHA, and that 2 to 15 grams a day may increase bleeding time. The review found no sperm-parameter benefit from omega-3 anyway.

And a general caution that applies to all male fertility supplements: NCCIH warns that what is on the label may not match what is in the product, and that words such as standardized, verified or certified do not by themselves guarantee quality or consistency. Supplements are not approved before sale; under the FDA framework the manufacturer is responsible for safety and labelling.

What to do before buying anything

This is the part that changes outcomes more than any male fertility supplements can. The NICHD states that men are the only or a contributing cause in about 40 percent of couples, and that the most common issues are problems affecting how the testicles work, with varicocele the most common cause of a low sperm count. Hormone imbalances, blocked or absent ducts, chromosome conditions, diabetes, thyroid problems, undescended testicles, injury or infection also appear on that list.

MedlinePlus adds causes a supplement cannot touch, including cancer treatment, prolonged heat exposure, heavy alcohol or drug use, uncontrolled diabetes, obesity, smoking, certain medicines and a past testicular infection from mumps, and describes the workup: history and physical exam, sperm testing, hormone blood tests, sometimes a genital ultrasound and rarely a biopsy.

So the sequence is test first, then decide about male fertility supplements. Our male fertility guide and lifestyle changes with the best evidence cover the groundwork.

Where Fertility Factor 5 fits

We track Fertility Factor 5 because it is the product in the male fertility supplements category that our readers ask about. Keeping to what can be verified: the manufacturer states it contains LJ100, a patented Eurycoma longifolia extract, together with Panax ginseng, zinc, selenium and BioPerine, and offers a 67-day money-back guarantee described as 60 days plus a week for return shipping (official page read 26 October 2026).

The page does not print per-ingredient milligram amounts; it says the LJ100 content matches the amount used in a trial that gave 200 mg daily. Check the Supplement Facts panel yourself and compare the zinc and selenium figures against the ceilings in the table above, especially if you already take a multivitamin.

What it is not, on this evidence, is a treatment for infertility. Nothing in the 2025 review supports telling a reader that any product will produce a pregnancy. For our ingredient-level notes see the ingredients breakdown and our earlier look at how it is meant to work.

The verdict

Do male fertility supplements work? On the evidence as it stands: not for pregnancy or live birth, and only marginally and uncertainly for a few sperm measurements. Anyone selling male fertility supplements on a bigger promise is ahead of the data.

Treat male fertility supplements as an optional extra while you get a semen analysis, address the causes a clinician can find, and fix the lifestyle factors that are free. If you take male fertility supplements anyway, stay under the upper limits, tell your doctor, and judge it by a repeat test rather than by how the month felt.

Check the current Fertility Factor 5 offer

Medical disclaimer: This article is for general information and is not medical advice. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. Infertility needs a proper medical assessment. Speak with a qualified health professional before starting any supplement, especially if you take medication or live with a health condition.

Questions people ask

Do male fertility supplements work for getting pregnant?

On the outcome that matters most, no. The 2025 Nutrients review pooled 50 randomized trials and found no effect of dietary supplements on pregnancy or live birth. That is the honest answer to do male fertility supplements work, and it is the result the marketing rarely quotes.

Did anything improve at all in the review?

Yes, but only single sperm measurements. Zinc with folic acid and supplements containing three or more substances improved sperm concentration; selenium, carnitine and coenzyme Q10 improved motility; alpha-lipoic acid improved normal morphology. Vitamin D, vitamin E and omega-3 showed no improvement in sperm parameters.

How strong is that evidence?

Weak. The review reports that most studies had some concerns or a high risk of bias, and that the certainty of evidence was generally low or very low. Its own conclusion is that there is no convincing evidence of an effect of any dietary supplement on male infertility.

Why does better motility not mean a baby?

Sperm measurements are surrogate markers. A number on a lab report can move without the couple being more likely to conceive. The NIH carnitine fact sheet makes the same point: a 2022 Cochrane review found carnitine increased motility and concentration at some timepoints but did not affect rates of live birth or pregnancy.

Should I take zinc for fertility?

The NIH fact sheet on zinc does not discuss zinc for male fertility, sperm or testosterone. The RDA for adult men is 11 mg a day and the upper limit is 40 mg. Fifty milligrams or more for several weeks can interfere with copper absorption and lower copper status.

Is selenium safe to supplement?

The NIH says there is not enough data to determine whether selenium supplements significantly affect male fertility. The RDA for adult men is 55 micrograms and the upper limit for adults is 400 micrograms; chronic excess causes selenosis, with hair loss and brittle nails among the first signs.

What should I do before buying male fertility supplements?

Get a semen analysis and a medical assessment. Male infertility is often caused by something a capsule cannot fix, such as a varicocele, a hormone problem, a duct blockage, diabetes, or a past infection. Testing tells you what you are actually treating.

How long would a fair trial of a supplement take?

The review only included randomized trials with treatment lasting twelve weeks or longer, so anything judged after a few weeks is judged too early. Ask your clinician when to repeat the semen analysis rather than guessing from how you feel.

What is in Fertility Factor 5?

The manufacturer states it contains LJ100 (a patented Eurycoma longifolia extract), Panax ginseng, zinc, selenium and BioPerine, with a 67-day money-back guarantee. The page does not print per-ingredient milligram amounts, so check the Supplement Facts panel before ordering (page read 26 October 2026).

So is it ever worth trying one?

Whether to try male fertility supplements is a personal decision, and it should be an informed one. If you want to try a product while you work through proper testing, pick one whose label you can read, keep taking nothing above the upper limits above, tell your doctor, and judge it by a repeat semen analysis rather than by hope.

Sources we opened for this article

• Effect of Dietary Supplements on Male Infertility in Terms of Pregnancy, Live Birth, and Sperm Parameters, Nutrients 2025 (Europe PMC, PMID 40431450)
• NIH Office of Dietary Supplements, Carnitine
• NIH ODS, Zinc
• NIH ODS, Selenium
• NIH ODS, Folate
• NIH ODS, Omega-3 Fatty Acids
• NIH ODS, Dietary Supplements consumer fact sheet
• NIH ODS, Dietary Supplements: What You Need to Know
• NCCIH, Using Dietary Supplements Wisely
• U.S. Food and Drug Administration, Dietary Supplements
• NICHD, What causes male infertility
• MedlinePlus, Infertility

Related reading on this site

• The male fertility guide
• Male fertility vitamins: honest evidence checks
• Comparing male fertility supplements
• Does Fertility Factor 5 work
• Fertility Factor 5 ingredients
• Fertility Factor 5 ingredients review
• Fertility Factor 5 reviews
• Fertility Factor 5 compared with other formulas
• How to improve male fertility naturally
• Lifestyle changes for male fertility
• Cortisol and fertility
• What is DIM