Male fertility problems often have no obvious symptoms. This guide explains when to seek advice, how male fertility is assessed and what may happen next.
Male fertility describes the ability to contribute to a pregnancy. It depends on producing enough functioning sperm, moving sperm through the reproductive tract, ejaculating semen and having intercourse or insemination at a time when an egg can be fertilised. A difficulty at any of these stages may reduce the chance of conception.
The World Health Organization defines infertility as failure to achieve a pregnancy after 12 months or more of regular unprotected sexual intercourse. Male factors contribute to about half of couples presenting with infertility, but fertility is assessed as a shared clinical issue rather than assigned to one partner. Both partners should usually be investigated at the same time.
WHO estimates that about one in six people of reproductive age experience infertility during their lifetime. This is a population estimate, not the chance that a particular couple will have a fertility problem.
Male infertility is diagnosed when a problem with the male reproductive system reduces the chance of pregnancy. It is not the same as sterility. Some men with reduced semen parameters conceive naturally, while some couples do not conceive even when an initial semen analysis is within its reference ranges.
A semen analysis is central to assessment, but it cannot by itself label a man as fertile or infertile. The result needs to be considered alongside how long the couple has been trying, the age and reproductive health of the partner trying to become pregnant, medical and sexual history, examination findings and any other relevant tests.
Often there are no symptoms. A man may feel well, have erections and ejaculate normally, yet have a low sperm count or another semen abnormality. Difficulty conceiving is therefore the most common reason for testing.
Symptoms or history that warrant an earlier medical discussion include:
A new testicular lump or swelling should be assessed promptly by a GP. Sudden, severe testicular pain requires urgent medical assessment and should not wait for a fertility appointment.
Under NICE guideline NG257, both partners should be offered further clinical assessment if pregnancy has not occurred after one year of regular unprotected vaginal intercourse and there is no known cause.
Referral should be considered at presentation rather than after a year when:
People using artificial insemination are assessed on a different timetable. NICE recommends clinical assessment after six unsuccessful cycles when there is no known cause, with the partner included when partner sperm is being used.
| Situation | When to seek advice | Why |
|---|---|---|
| No known fertility risk | After 12 months of regular unprotected vaginal intercourse without pregnancy | This is the standard point for assessment under NICE guidance |
| Partner trying to become pregnant is aged 36 or over | At presentation; do not wait a full year before asking for advice | Age influences the available time and choice of fertility treatment |
| Known or suspected fertility risk in either partner | At presentation | Earlier investigation may identify a cause that needs treatment |
| Potentially fertility-damaging treatment is planned | Before treatment, as early as possible | There may be an opportunity to preserve sperm |
A clinician will ask about previous pregnancies, how long you have been trying, the frequency and timing of sex, erections and ejaculation. They may also ask about childhood testicular problems, infections, surgery, long-term health conditions, prescribed medicines, supplements, recreational drugs, work exposures, smoking and alcohol.
Give an accurate account of testosterone or anabolic-steroid use, including products obtained outside medical care. Exogenous testosterone can suppress the hormonal signals needed for sperm production. Do not stop prescribed treatment without speaking to the clinician who manages it.
A semen analysis measures the semen and the sperm within it. It commonly reports semen volume, sperm concentration, total sperm number, movement and shape. One result is not a complete fertility forecast, and samples from the same man can vary.
If the first analysis is abnormal, NICE recommends a repeat confirmatory test. This is ideally performed around three months later, although a result showing no sperm or a severe sperm deficiency should be repeated as soon as possible.
After two or more abnormal semen analyses, NICE recommends examination of the scrotum and testes and consideration of blood tests for testosterone and gonadotrophins. Examination may identify a varicocele, a difference in testicular size, an absent vas deferens or another finding that changes the investigation.
Hormone tests are not interpreted in isolation. Timing, symptoms, medicines and the pattern of luteinising hormone and follicle-stimulating hormone may help distinguish a testicular problem from a problem in the hormonal signalling system.
Genetic testing is reserved for defined situations. Current NICE guidance recommends Y-chromosome microdeletion testing for idiopathic azoospermia or a sperm concentration below 1 million per ml, CFTR testing when obstructive azoospermia or an abnormal vas deferens is suspected, and karyotyping for idiopathic azoospermia. Karyotyping may also be considered when the sperm concentration remains below 5 million per ml.
An ultrasound is not required for every man. A specialist may arrange one when the history, examination or semen results suggest a testicular abnormality, obstruction or another condition that needs imaging.
NICE does not recommend sperm DNA fragmentation testing as part of the standard fertility investigation. Tests marketed directly to consumers may therefore go beyond the routine UK pathway without showing that they will alter treatment.
The World Health Organization reference values describe the lower fifth centile among men whose partners conceived within 12 months. They are not a boundary between fertility and infertility. A value below a reference point can indicate that further assessment is appropriate, while a value above it does not guarantee pregnancy.
Interpretation should consider all semen measures together. For example, concentration may be reduced while the total number of motile sperm remains clinically useful. Conversely, a concentration within range does not exclude a problem with movement, ejaculation or the reproductive health of either partner.
The next step depends on the cause, its severity and both partners' circumstances. Options may include:
Treatment should address a defined problem where possible. Current NICE guidance advises against androgens for semen abnormalities and against supplements or antioxidants intended to improve sperm DNA integrity. ICSI is considered when semen parameters are abnormal, when sperm have been surgically retrieved or after failed or very low fertilisation with standard IVF; it is not an automatic upgrade for every IVF cycle.
Male fertility can decline with age, although NICE describes the effect as smaller than the age-related decline in female fertility. There is no single birthday at which a man becomes infertile. Age is considered alongside health, sexual function, semen results, the partner's age and the time already spent trying to conceive.
NICE advises vaginal intercourse every two to three days to optimise the chance of pregnancy. There is usually no need to restrict intercourse to a single predicted fertile day. Smoking cessation, avoiding excessive alcohol, working towards a healthy weight and reviewing medicines or workplace exposures with a clinician support general and reproductive health, but none can guarantee a pregnancy.
Do not start over-the-counter fertility supplements or stop a prescription medicine on the strength of an online article. A medication review should balance fertility with the condition being treated.
