Infertility is defined as not being able to conceive after 12 months of having regular unprotected sexual intercourse. About one in 6 couples in Australia will have a problem with conceiving.
About 40 per cent of infertility cases involve a male factor; in another 40 per cent of cases there is a female factor; and in the remaining cases there is either a combination of male and female factors (10 per cent), or no identifiable cause (10 per cent).
There are numerous causes of infertility in men, however, most commonly there will be problems with sperm. These include problems with sperm numbers, where there are either too few sperm or, in some cases, no sperm at all (called azoospermia). There may also be problems with sperm quality, where some of the sperm are abnormally shaped (abnormal morphology) or are poor swimmers (poor motility).
Causes of azoospermia may include reduced production of sperm due to a hormonal problem (such as too little testosterone), a chromosomal abnormality (genetic problem) or certain infections (such as mumps infection of the testis).
Azoospermia may also be the result of a blockage of the passage of sperm from the testes, where they are produced, to the urethra. This may be due to infection or injury involving the area, surgery (vasectomy) or the absence of the tube from the testis to the urethra (vas deferens).
Couples having difficulty conceiving should see their doctor, ideally together, for an initial assessment. This will usually involve the doctor taking a history of the problem and performing an examination.
Further investigations will depend on the findings of the assessment and what is likely to be the cause of the problem.
The most important investigation in men is the semen analysis. A specimen of semen is collected after abstaining from sexual intercourse for 2-5 days beforehand. The sample must be delivered to the laboratory within one hour of collection. The specimen is analysed for volume and sperm numbers, motility and morphology.
Other investigations may include testing for sperm antibodies, and measuring the blood levels of testosterone and other hormones. If there are no sperm or the sperm numbers are very low, an ultrasound scan of the testes may be performed. A biopsy of the testes may also be carried out.
Options for the treatment of infertility will depend on the cause of the problem.
Last Reviewed: 28 April 2006