When a couple has difficulty conceiving, it is easy to assume the problem lies with the woman. It often does not. Male factors contribute to around half of all fertility problems — either alone or alongside a female factor.

That is why both partners should be assessed from the start. Testing the man is simple, quick and non-invasive, and it makes no sense to investigate one partner thoroughly while leaving the other untested.

Semen analysis: the first test

Semen analysis is the cornerstone of male fertility assessment. A sample is produced after 2 to 7 days without ejaculation and examined in a laboratory, usually within an hour of production.

It measures:

  • Volume — how much fluid there is
  • Concentration and total count — how many sperm are present
  • Motility — how well they move; sperm that cannot swim well cannot reach the egg
  • Morphology — their shape; abnormally shaped sperm may struggle to fertilise an egg

One abnormal result is not a diagnosis

This is important. Sperm production varies considerably from month to month, and a single poor result may reflect a recent illness, a fever, stress, or simply natural variation. An abnormal result should be repeated, usually after about three months — which is roughly how long it takes to produce a new cycle of sperm.

Do not draw conclusions, or make decisions, from one test.

What the results can show

  • Low sperm count — fewer sperm than expected
  • Reduced motility — sperm present but not moving well
  • Abnormal morphology — a high proportion of unusually shaped sperm
  • No sperm in the sample — which needs further investigation, as the cause may be a blockage rather than a production problem, and blockages can sometimes be treated

Results are usually a matter of degree rather than a yes or no. Many men with below-average results still father children naturally.

What can be improved

This is the part a man can act on directly, and it is worth doing before or alongside any treatment:

  • Stop smoking — it reduces count, motility and quality
  • Cut down alcohol — heavy drinking lowers testosterone and sperm production
  • Avoid recreational drugs, and anabolic steroids in particular — these can shut down sperm production entirely, sometimes for a long time after stopping
  • Get to a healthy weight — obesity affects hormone levels and sperm quality
  • Keep the testicles cool — avoid prolonged hot baths, saunas and very tight underwear, and take breaks from long periods sitting
  • Review medicines with a doctor, as some affect fertility

Because sperm take around three months to develop, changes made now show up in tests about three months later. Patience is part of it.

Other causes worth looking for

A doctor may examine for a varicocele (enlarged veins in the scrotum), look for evidence of past infection or injury, check hormone levels, or consider whether a previous operation or an inherited condition is relevant. Some of these are treatable in their own right.

Treatment options

Where results cannot be improved enough, assisted conception can help. Which is appropriate depends on how significant the problem is, and on the female partner's assessment too.

  • Intrauterine insemination (IUI) — prepared sperm is placed directly into the womb around ovulation. Useful for mild reductions in count or motility.
  • In vitro fertilisation (IVF) — eggs are collected and fertilised with sperm in the laboratory, and an embryo is transferred to the womb.
  • ICSI — a single sperm is injected directly into an egg. This is the treatment used for severe male factor problems, and it means that very low numbers of sperm can still achieve fertilisation.
  • Donor sperm — an option where no sperm can be retrieved, or where there is an inherited condition a couple does not wish to pass on.

A word about how this feels

Men are often less prepared for a fertility diagnosis than women, talk about it less, and can take it hard. It is worth saying plainly: a low sperm count is a medical finding, not a judgement on anyone, and in most cases there is something that can be done. Talking to your partner, and to your doctor, is better than carrying it quietly.

The bottom line

Male factors account for around half of fertility problems, so both partners should be tested from the outset. Semen analysis is simple, and an abnormal result should always be repeated before conclusions are drawn. Lifestyle changes genuinely help and show up about three months later. Where treatment is needed, options run from IUI through IVF to ICSI, which can work even when very few sperm are available.

References

  1. National Institute for Health and Care Excellence. Fertility problems: assessment and treatment. NG257. London: NICE; 2026. Available from: https://www.nice.org.uk/guidance/ng257
  2. National Health Service. Infertility [Internet]. NHS; [cited 2026 Jul 22]. Available from: https://www.nhs.uk/conditions/infertility/
  3. World Health Organization. WHO laboratory manual for the examination and processing of human semen. 6th ed. Geneva: WHO; 2021.