Male factor is involved in roughly half of all cases where a couple struggles to conceive, yet most of the conversation about fertility still centres on women. This guide is for men who want straight answers: what actually lowers sperm quality, how testosterone fits in (and why testosterone therapy is often the wrong move for a man trying to conceive), which fertility supplements have real evidence behind them, and when it is time to stop guessing and get tested.
Table of Contents
- Signs of male infertility
- What causes fertility problems in men
- Low testosterone and fertility
- Male fertility after 40
- Natural ways to improve male fertility
- Male fertility supplements: what the evidence says
- Foods that support sperm health
- When to see a doctor
- Frequently asked questions
Signs of Male Infertility
The frustrating truth is that most male infertility has no symptoms at all. A man can feel perfectly healthy, have a normal sex drive and normal erections, and still have a low sperm count. The only reliable way to know is a semen analysis.
That said, some signs raise the likelihood of a problem and are worth acting on:
- A couple has been trying for 12 months without success (6 months if the female partner is over 35).
- A history of undescended testicles, testicular injury, mumps after puberty, or chemotherapy.
- A swelling or “bag of worms” feeling in the scrotum, which can indicate a varicocele.
- Very low semen volume, or pain or difficulty with ejaculation.
- Symptoms of low testosterone: low libido, fatigue, loss of muscle, reduced facial or body hair, breast tissue growth.
- Erectile dysfunction, which does not itself cause infertility but often shares causes with it.
What Causes Fertility Problems in Men
Sperm production depends on a chain: the brain signals the testes with two hormones (LH and FSH), the testes produce testosterone and sperm, the sperm mature over about 74 days, and they are delivered through a set of ducts. A problem anywhere in that chain shows up as a lower count, poorer movement or abnormal shapes.
| Cause | How it affects fertility | How common |
|---|---|---|
| Varicocele | Raises testicular temperature, lowering count and motility | Found in about 40 percent of men evaluated for infertility |
| Hormonal disorders | Low LH/FSH signalling or low testosterone reduces sperm production | Less common, but very treatable |
| Obesity | Fat tissue converts testosterone to oestrogen; raises scrotal temperature | Increasingly common |
| Smoking, heavy alcohol, cannabis | Sperm DNA damage, lower count and motility | Common and reversible |
| Heat exposure | Hot tubs, saunas, laptops on the lap, tight underwear | Common, mild effect |
| Medications | Testosterone therapy, anabolic steroids, some antidepressants, finasteride, chemotherapy | Often overlooked |
| Infections | Past STIs, mumps orchitis, prostatitis | Variable |
| Chronic stress and poor sleep | Raises cortisol, suppresses testosterone signalling | Common, modest effect |
| Genetic factors | Chromosome abnormalities, Y-chromosome deletions | Around 10 to 15 percent of severe cases |
Our guide to environmental exposures and sperm health covers the chemical and heat factors in more detail.
Low Testosterone and Fertility
Can low testosterone cause infertility? Yes. Testosterone inside the testes needs to be very high, roughly 50 to 100 times the level in the blood, to drive sperm production. When the brain’s signalling to the testes falls (a condition called hypogonadotropic hypogonadism), both testosterone and sperm output drop. Men in this situation typically have low libido, low energy and a low count together.
Here is the part most men do not know, and it matters enormously: taking testosterone makes infertility worse, not better. When you take testosterone from outside, the brain senses high levels and shuts off LH and FSH. The testes stop making their own testosterone and sperm production can fall to zero within months. This is why testosterone replacement is essentially a contraceptive, and why a man who wants children should never start it without a fertility conversation first. The same applies to anabolic steroids.
For men who have low testosterone and want to conceive, doctors use different tools: clomiphene or enclomiphene, which stimulate the brain’s signal, or hCG injections, which mimic LH directly. These raise testosterone while preserving or improving sperm production. Recovery of sperm after stopping testosterone therapy is possible but can take 6 to 18 months.
If you suspect low testosterone, the first step is a morning blood test, repeated if low. Our hormone imbalance test guide explains what to ask for.
Male Fertility After 40
Men do not have a hard fertility cut-off the way women do, but the idea that male fertility is ageless is a myth. From the late 30s onward, semen volume, motility and the proportion of normally shaped sperm decline gradually, and sperm DNA fragmentation rises. Research links older paternal age to longer time to conception, slightly higher miscarriage rates and a modest increase in some conditions in children. Most men over 40 who are otherwise healthy do conceive, but it may take longer, and the lifestyle factors below matter more with each decade. Our article on men’s biological clock goes deeper.
Natural Ways to Improve Male Fertility
Because sperm take about three months to develop, any change you make now shows up in a semen analysis roughly 90 days later. These are the changes with the best evidence, in rough order of impact.
- Stop smoking and cut alcohol. Smoking is consistently associated with lower count and motility and higher DNA damage. Heavy drinking lowers testosterone. Cannabis lowers count and motility in several studies.
- Lose abdominal weight if you carry it. Weight loss in obese men improves sperm parameters and testosterone in multiple trials.
- Keep the testes cool. Skip hot tubs and saunas while trying, keep laptops off your lap, and prefer looser underwear. The effect is modest but free.
- Sleep seven to eight hours. Short sleep is associated with lower testosterone and lower count.
- Exercise moderately. Regular moderate activity improves parameters; extreme endurance training and steroid use worsen them.
- Manage stress. Chronic stress raises cortisol and suppresses the brain’s signal to the testes. Trying to conceive is itself stressful; our guide on protecting your relationship during fertility challenges is worth a read.
- Review your medications. Ask a pharmacist whether anything you take affects sperm. Finasteride, some antidepressants, some blood pressure drugs and testosterone all can.
- Get a varicocele checked. Repair improves sperm parameters in many men and is one of the few surgical fixes for male infertility.
Male Fertility Supplements: What the Evidence Says
The fertility supplement market is large and the evidence is uneven. Here is an honest summary. The single most important study to know is the 2020 FAZST trial, which gave 2,370 men zinc and folic acid for six months and found no improvement in semen quality or live birth rates compared with placebo. That does not mean nothing works, but it should temper expectations.
| Ingredient | Evidence for sperm parameters | Notes |
|---|---|---|
| Coenzyme Q10 | Moderate: several trials show improved motility and concentration at 200 to 300 mg/day | Best-supported single antioxidant |
| L-carnitine | Moderate: improved motility in several trials at 2 to 3 g/day | Often combined with CoQ10 |
| Zinc | Helps if deficient; no benefit in the large FAZST trial for men with normal levels | Do not exceed 40 mg/day |
| Vitamin D | Correcting deficiency improves motility in some trials | Test first; common deficiency in Canada |
| Selenium and vitamin E | Mixed; some improvement in motility when combined | Avoid high-dose selenium |
| Folic acid | No benefit in FAZST | Fine as part of a multivitamin |
| Ashwagandha | Small trials show improved count and motility, possibly via stress reduction | Early evidence |
| Maca root | Small trials show improved concentration; motility mixed | See our maca root guide |
| Tribulus terrestris | Weak; does not raise testosterone in healthy men | See Tribulus side effects |
A reasonable evidence-based approach is CoQ10 plus L-carnitine, correction of any measured vitamin D or zinc deficiency, and a general multivitamin, taken for at least three months before re-testing. Anything beyond that is optional. A summary of the mineral evidence is in our article on zinc and other vitality ingredients.
It is a general herbal supplement, not a fertility product, and no claims are made that it improves sperm quality, testosterone or fertility. If conception is the goal, the ingredients in the table above are where the evidence is.
Foods That Support Sperm Health
Diet patterns matter more than individual foods. Men who eat a Mediterranean-style diet, high in vegetables, fruit, fish, nuts, olive oil and whole grains, consistently show better semen parameters than men who eat a lot of processed meat, sugar and fried food. Specific foods with supporting evidence include walnuts (75 g a day improved motility in one trial), oily fish, eggs, leafy greens, berries, tomatoes (lycopene) and pumpkin seeds (zinc). Our guide to the best foods for sperm health turns this into a shopping list.
When to See a Doctor
See a doctor, and ask for a semen analysis, if you have been trying for a year, or six months if your partner is over 35, or right away if you have any of the risk factors listed under signs above. A semen analysis costs little, takes a few days, and tells you far more than any amount of supplementation. Our guide to sperm testing explains the numbers, and if you prefer to start privately, at-home sperm tests are a reasonable first screen. If the result is abnormal, a urologist or fertility specialist can check hormones, examine for varicocele and discuss options ranging from lifestyle change to assisted reproduction.
Can low testosterone cause infertility in males?
Yes. Low signalling from the brain lowers both testosterone and sperm production. But taking testosterone makes it worse; fertility-preserving treatments like clomiphene or hCG are used instead.
Do male fertility supplements work?
Some, modestly. CoQ10 and L-carnitine have the best evidence for motility. Zinc and folic acid did not help in the largest trial. No supplement fixes a varicocele, a blocked duct or a genetic cause.
How long do fertility supplements take to work?
At least three months, because that is how long a sperm takes to develop. Re-test after 90 days.
What are the first signs of low sperm count?
Usually there are none. Difficulty conceiving is the main sign, which is why testing matters.
Does erectile dysfunction mean I am infertile?
No. ED affects delivery, not sperm production, though the two share causes such as low testosterone and vascular disease. Our guide to ED treatment options covers that side.
Can stress cause male infertility?
Chronic stress lowers testosterone signalling and is associated with poorer semen quality. It is rarely the sole cause, but it is worth addressing.
References
- Schisterman EF et al. Effect of folic acid and zinc supplementation in men on semen quality and live birth among couples undergoing infertility treatment: the FAZST randomized clinical trial. JAMA. 2020. PubMed
- Salas-Huetos A et al. The effect of nutrients and dietary supplements on sperm quality parameters: a systematic review and meta-analysis of randomized clinical trials. Advances in Nutrition. 2018. PubMed
- Patel AS et al. Testosterone is a contraceptive and should not be used in men who desire fertility. World Journal of Men’s Health. 2019. PMC6305865
Important Health Information
This article is general information and is not a substitute for professional medical advice, diagnosis or treatment. Speak to a doctor or pharmacist before starting any supplement, especially if you have a medical condition or take medication.
About ErecteMax
ErecteMax Herbal Supplement Capsules for Men contain maca root (85 mg), saw palmetto (45 mg) and tribulus terrestris (45 mg) per capsule. ErecteMax is not licensed by Health Canada, has no NPN and makes no health claims. See the product page for the full label.
Medical disclaimer: This article is general information, not medical advice, and it is not a substitute for a consultation with a qualified health professional. ErecteMax is a herbal supplement, not a medicine. It does not hold a Natural Product Number (NPN) or any product licence from Health Canada, and no claims are made that it treats, prevents or improves any condition. Speak to a doctor or pharmacist before starting any supplement or treatment, especially if you take prescription medication, have a heart condition or are being treated for another medical problem. Read our full medical disclaimer.