Infertility is still discussed as though it were a woman's problem. It isn't. Male factors contribute to roughly half of all cases, either alone or alongside a female factor — yet in a great many couples the man is never properly assessed, and treatment proceeds on the assumption that the issue lies elsewhere.
That is a costly omission, because a semen analysis is cheap, non-invasive and fast, and because some male causes are straightforwardly treatable.
Both partners should be assessed at the same time, from the start. Investigating the woman first and the man months later delays everything and occasionally leads to invasive treatment of a woman whose fertility was never the limiting factor.
When to seek help
The usual threshold is twelve months of regular unprotected intercourse without conception, or six months if the female partner is over 35, since time matters more then.
Seek advice sooner — don't wait out the year — if there is:
- A history of undescended testis, testicular surgery or torsion
- Previous chemotherapy, radiotherapy, or mumps affecting the testes after puberty
- A known varicocele
- Erectile or ejaculatory difficulty
- Previous vasectomy or hernia repair
- Anabolic steroid or testosterone use, current or past
That last one deserves emphasis. Testosterone supplementation suppresses sperm production — often profoundly. Men taking testosterone for gym performance or for "low T" are frequently unaware that it works as a contraceptive. It is usually reversible, but recovery takes months.
What a semen analysis actually tells you
This is the cornerstone test. It reports several things, and the total count is not the most important:
- Volume — how much fluid
- Concentration — sperm per millilitre
- Total count — concentration × volume
- Motility — the proportion swimming, and how well. Often more predictive than count
- Morphology — the proportion normally shaped
- Vitality — the proportion alive
Two things patients are rarely told, both important:
The reference values are not a pass mark. They come from the lowest fifth percentile of men who fathered a child within a year. So a man below the threshold is at the lower end of the fertile distribution — not sterile. Men below the cut-offs conceive naturally all the time, and men above them sometimes struggle.
One test is not enough. Sperm production takes about three months, and is affected by recent fever, illness, heat, alcohol and abstinence period. An abnormal result should always be repeated after several weeks before any conclusion is drawn. Decisions made on a single sample are made on incomplete information.
For collection: two to five days of abstinence, and the sample should reach the lab within an hour, kept close to body temperature.
What causes low sperm counts
Varicocele — the most common correctable cause. Covered below.
Hormonal problems. Low testosterone driven by a pituitary issue, thyroid disorder, or a raised prolactin level. These are found on blood tests and some are treatable with medication alone.
Obstruction. Blockage anywhere from the testis to the urethra — from previous infection, surgery, vasectomy, or congenital absence of the vas deferens.
Genetic causes. Klinefelter syndrome and Y-chromosome microdeletions, which is why genetic testing is offered when counts are very low.
Infection of the epididymis or prostate.
Medication. Testosterone and anabolic steroids, some chemotherapy, sulfasalazine, and certain antifungals.
Ejaculatory problems, including retrograde ejaculation, where semen passes backwards into the bladder — common in diabetes and after some prostate surgery.
Unexplained. In a meaningful proportion, no cause is identified even after thorough evaluation. That is frustrating but honest.
Varicocele — the treatable one
A varicocele is a collection of dilated, tortuous veins around the testis — essentially varicose veins of the scrotum. It is present in around a third of men with primary infertility, far above the background rate.
The mechanism is temperature. Pooled blood warms the testis, and sperm production is exquisitely heat-sensitive. Varicoceles are much more common on the left for anatomical reasons relating to how the left testicular vein drains.
Most are painless and found on examination. Some cause a dragging ache, worse at the end of the day.
Not every varicocele needs fixing. Repair is considered when it is palpable on examination, semen parameters are abnormal, the couple has documented infertility, and the female partner's fertility is adequate or treatable. A varicocele visible only on ultrasound, in a man with a normal semen analysis, is generally left alone — a distinction worth knowing, as unnecessary varicocele surgery does happen.
When it is indicated, microsurgical repair improves semen parameters in a substantial proportion of men, with improvement typically appearing over three to six months, in line with the sperm production cycle.
Zero sperm count is not the end of the discussion
Azoospermia — no sperm in the ejaculate — sounds final. It usually isn't, and the distinction that matters is this:
Obstructive azoospermia: production is normal, but the pathway is blocked. Sperm can almost always be retrieved surgically, and in some cases the blockage itself can be reconstructed.
Non-obstructive azoospermia: production itself is impaired. Even here, sperm can often be found within the testis using microsurgical retrieval, and used with ICSI — where a single sperm is injected directly into an egg.
Telling these apart uses hormone levels, testicular volume, genetic testing and sometimes a biopsy. The practical message: a zero count on a semen sample is a reason to see a urologist, not a verdict.
What you can change yourself
These matter more than most men expect, and all act over roughly a three-month cycle:
- Stop smoking. It reduces count, motility and DNA integrity.
- Cut alcohol to modest levels.
- Stop anabolic steroids and testosterone. Non-negotiable if you want to conceive.
- Lose excess weight. Obesity raises oestrogen and scrotal temperature.
- Avoid prolonged heat — hot tubs, saunas, laptops on the lap, long-haul driving.
- Control diabetes and review any long-term medication with your doctor.
- Timing. Intercourse every two to three days through the cycle beats trying to pinpoint ovulation, and is considerably less stressful.
Frequently asked questions
When should we seek help?
After twelve months of trying, or six if your partner is over 35. Sooner if there's a history of undescended testes, testicular surgery, chemotherapy, steroid use or erectile difficulty.
Does one abnormal semen analysis mean I'm infertile?
No. Production varies with illness, fever, heat and abstinence. Always repeat an abnormal result after several weeks before concluding anything.
Does a varicocele always need surgery?
No. Repair is for palpable varicoceles with abnormal semen parameters in couples with documented infertility. One seen only on ultrasound with a normal semen analysis is generally left alone.
Can a man with zero sperm count father a child?
Often yes. Sperm can frequently be retrieved surgically and used with ICSI, even when none appear in the ejaculate.
Do supplements help?
Antioxidant supplements are widely sold and the evidence is weak and inconsistent. They're unlikely to harm, but they are not a substitute for identifying a treatable cause.
Medically reviewed by Dr. Navdeep Garg, MCh (Urology), FEBU. This article is general information about urological conditions and does not constitute medical advice. Treatment decisions depend on individual assessment. For any medical concern, please consult a qualified physician.