Male infertility – the causes and treatments

Common causes of male infertility

Male infertility is caused by an absence of sperm or sperm of a poor quality.

Poor sperm quality 

Sperm quality and quantity can vary greatly and is affected by your health and nutrition. All semen contains a proportion of poor sperm that can be abnormally-shaped or unable to swim; the problem occurs when there aren’t enough good sperm – sometimes there are no sperm at all.

In some cases it is possible to boost sperm production through lifestyle changes, supplements or medication and this might be sufficient to improve your chances of natural conception. Other options include: intrauterine insemination (IUI), where the sperm is injected high into the uterus; or IVF, where the eggs are collected and a single sperm injected sperm directly into the egg, a process called ICSI.

Lack or absence of sperm 

There are two main reasons for a low or zero sperm count. The first is that the sperm are not being made in the testes (non-obstructive) this can be a hormonal issue. The second is where a blockage prevents the sperm from reaching the ejaculate (obstructive).

It is important that men with absent or low sperm numbers are thoroughly investigated, to ensure that they do not have an underlying illness causing their infertility or a genetic problem. For example, some men are carriers for the cystic fibrosis gene and may be unaware as they do not have any symptoms of the condition, however, this can mean they have been born without a vas deferens.

If a genetic issue is identified then the couple can be counselled about the chances of passing a genetic problem onto their offspring, and also about the chances of success if surgical sperm retrieval is required.

Non-obstructive causes of male infertility

The manufacture of sperm can be affected by a number of problems, including:

• Genetic conditions, such as Y chromosome microdeletion or Kleinfelters syndrome, may cause there to be no sperm or very reduced number of sperm in the ejaculate.
• Testicular problems, such as undescended testicles or a previous twisted testicle, may render the testicle unable to produce sperm.
• Toxins – some drugs including steroids used in weight training and chemotherapy, may damage the testicles’ ability to manufacture sperm.
• Previous illness, such as measles may impair sperm production by the testicles.
• A hormonal problem (hypogonadotrophic or hypogonadism) can lead to insufficient hormones being available to support sperm manufacture.

Obstructive causes of male infertility

There are many reasons why the tubes that transport the sperm can become blocked and these include: sports injuries; infections, such as mumps, chlamydia or gonorrhoea; birth defects or a previous vasectomy or failed vasectomy reversal.

Another common problem is a varicocele, which is a collection of dilated veins which surround the testicle. The veins may visible when the man stands up and may cause discomfort or aching.

The link between varicocele and fertility is much debated. Although varicoceles are present in 30 to 40 per cent of men with infertility, many men with the condition are able to conceive without problems. Correction of the varicocele may lead to improvement in sperm number and quality, so it is recommended that a significant varicocele should be treated to try and improve sperm quality.

Unexplained and combination infertility

Unexplained infertility accounts for 25 per cent of all fertility problems and is a term used when doctors can’t find a cause for infertility after a full series of tests and assessments.

Sometimes being significantly overweight or underweight, exercising excessively or even environmental toxins may be contributing factors. Improving your lifestyle, with better nutrition and regular unprotected intercourse (twice a week) may be sufficient to conceive. However if you still haven’t conceived after two years of trying (including the year before fertility investigations) IVF is usually considered the best option.

Combination infertility – this is where there are both male and female infertility problems, or when one partner has more than one fertility problem. A combination is diagnosed in about 40 per cent of cases. Symptoms vary, depending on causes and so do the treatments.

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