Male Factor Infertility: Sperm Problems, Tests, Causes and Treatment
Key takeaways
- Male factor is involved in roughly a third to half of couples who struggle to conceive, so testing the sperm matters just as much as testing the female partner.
- A semen analysis is the key first test; it measures sperm count, motility (movement) and morphology (shape), and an abnormal result is usually repeated before any conclusion.
- Causes range from hormonal and genetic issues to varicoceles, infections, lifestyle factors and previous surgery; for many men no clear cause is found.
- Treatment depends on the result; ICSI, injecting a single sperm into each egg, helps many couples conceive even with very low counts or poor motility.
- If you have been trying for over a year (or six months if the female partner is over 35), both partners should be tested together; do not delay seeing your GP.
Male factor infertility means a problem with the sperm, or how it is delivered, that contributes to a couple’s difficulty conceiving. It is far more common than many people expect: a male factor is involved in roughly a third to half of couples who struggle to get pregnant. That single fact reframes everything, because it means the man should be tested from the start, not as an afterthought.
When we were finally referred, I remember being braced for the focus to be entirely on me. Instead the clinic tested us both on the same day. That felt fair, and it is exactly how it should work.
How common is male factor infertility?
A male factor is involved in roughly a third to half of couples who struggle to conceive, according to NICE and the NHS. Sometimes it is the sole cause; often it sits alongside a female factor, which is why both partners are assessed together. Testing only one half of a couple misses a large share of the picture and wastes time you may not have. If you have been trying for over a year (or six months if the female partner is over 35), this is the point to see your GP, as we set out in when to see a doctor about fertility.
What the semen analysis measures
The semen analysis is the key first test for the male partner, and it looks at three things in particular. Count, motility and morphology together describe whether enough healthy, moving sperm are present.
Count (or concentration) is how many sperm are in the sample. Motility is the proportion that are moving, and how well they swim. Morphology is the proportion with a normal shape. Laboratories compare results against World Health Organization reference values; results below those values flag a possible problem rather than a certain one. Because sperm quality varies naturally from sample to sample, an abnormal result is usually repeated, often after about three months, before anything is concluded. The sample is best produced after about two to seven days without ejaculation and examined quickly, since timing and handling both affect the figures. This sits within the wider work-up we cover in fertility tests and investigations.
Common causes of sperm problems
Causes of male factor infertility are varied, and for a significant proportion of men no single cause is ever pinned down. The main groups are hormonal, structural, genetic, infective and lifestyle related.
A varicocele (enlarged veins in the scrotum) is one of the more common findings. Others include hormonal imbalances, genetic conditions, previous infections, undescended testes in childhood, certain medicines, and blockages that stop sperm reaching the ejaculate. Lifestyle factors such as smoking, heavy alcohol use, obesity and excess heat can reduce quality too. Because sperm take roughly three months to develop, any positive changes take a similar time to show in a result, which we explore in diet and lifestyle for fertility. Age matters for men too, though far less sharply than it does for women; sperm quality tends to drift down gradually with the years rather than dropping off a cliff, a contrast we set out in age and fertility.
Treatment, including ICSI
Treatment depends entirely on the cause and the severity of the result. For many couples with a male factor, ICSI offers the best chance, because it needs only a small number of healthy sperm.
ICSI (intracytoplasmic sperm injection) involves injecting a single sperm directly into each egg in the laboratory, rather than leaving egg and sperm to fertilise on their own. It can achieve fertilisation even when counts or motility are very low. Where there is no sperm in the ejaculate, sperm can sometimes be retrieved surgically from the testes and used for ICSI. We explain the procedure step by step in ICSI explained. Where a man’s own sperm cannot be used, donor sperm is another route some couples choose, and a fertility counsellor can help you think it through.
A semen analysis result can land hard, especially when there have been no symptoms and no warning. For us it helped to remember that an abnormal result is information, not a verdict, and that it pointed us toward a treatment that did eventually work.
This guide is general information and support, not a diagnosis or individual medical advice. Please see your GP or a fertility specialist about your own situation.
References
- Infertility, NHS.
- Diagnosing Male Infertility, American Society for Reproductive Medicine (ReproductiveFacts.org).
- Fertility problems: assessment and treatment (NICE guideline CG156), National Institute for Health and Care Excellence (NICE).
Frequently asked questions
What is male factor infertility?
Male factor infertility means a problem with the sperm or how it is delivered is contributing to a couple's difficulty conceiving. It is involved in roughly a third to half of couples who struggle to get pregnant, sometimes on its own and sometimes alongside a female factor. The usual sign is no pregnancy after about a year of regular unprotected sex, with the sperm issue found on a semen analysis rather than from symptoms.
What does a semen analysis measure?
A semen analysis measures the volume of the sample, the sperm count or concentration, motility (the proportion of sperm moving and how well), and morphology (the proportion of sperm with a normal shape). The World Health Organization publishes reference values laboratories compare against. Because results vary naturally, an abnormal result is usually repeated, often after about three months, before any firm conclusion is drawn.
Can you still have children with a low sperm count?
Yes. Many men with a low sperm count or poor motility go on to have children, sometimes naturally and sometimes with treatment. ICSI, where a single sperm is injected directly into each egg in the laboratory, can achieve fertilisation even when very few sperm are available. In some cases sperm can be retrieved surgically from the testes when none appears in the ejaculate.
What causes a low sperm count?
Causes include hormonal problems, genetic conditions, a varicocele (enlarged veins in the scrotum), previous infections, undescended testes, certain medicines, and lifestyle factors such as smoking, heavy drinking, obesity and heat. Previous surgery or injury can also play a part. For a significant proportion of men no specific cause is identified, which is frustrating but does not mean treatment cannot help.
Does male factor infertility have symptoms?
Usually not. Most men with a sperm problem have no symptoms at all and feel completely well; the issue only shows up on a semen analysis. Occasionally there are signs such as a swelling in the scrotum, problems with erection or ejaculation, or reduced facial or body hair, which can point to a hormonal cause worth investigating. The absence of symptoms is exactly why testing both partners early matters.
How can a man improve sperm quality?
Evidence supports stopping smoking, keeping alcohol within recommended limits, reaching a healthy weight, staying active and avoiding excess heat to the testes. Sperm take around three months to develop, so changes take time to show. These steps support general health and may help, but they are not a guaranteed fix; if you are concerned, get a semen analysis rather than relying on lifestyle changes alone.
Written by Emma Lawson. Medically reviewed by Dr Priya Nair, MBBS, MRCOG.
Our guides are written from personal experience and reviewed by a qualified clinician for accuracy. Read our editorial policy.