Semen analysis is the most important male infertility test. After collection, a drop of semen is assessed under a microscope in the laboratory to examine sperm function. Different aspects are looked at:

• Quantity - The number of individual sperm cells.
• Motility - The swimming capacity of the sperm.
• Morphology - The shape of the sperm.
• Vitality - The ability of the sperm to live and survive.

Different definitions are used to denote possible defects.

If the test is abnormal, the test will usually repeated to confirm these defects. If there has been any sign of illness such as fever in the preceding three months, the repeat test will probably be delayed for a couple of months or so. This is because the development of sperm from start to finish takes three months.

Sperm dysfunction is one of the major causes of subfertility. An assessment of the sperm often provides the explanation for a couple’s inability to get pregnant and also helps to determine their most suitable treatment options. For example, a very small number of sperm cells or sperm cells with very low motility may mean that advanced procedures are necessary, while in the case of a more normal semen analysis more conservative treatments can be pursued.

You will be provided with clear instructions about the method of collection. The sample is usually taken by masturbation, during which the semen (the ejaculate) is collected in a sterile sample pot. To get a reliable result, it is important to collect all of the ejaculation; and you should not use lubricants. Specially designed condoms for collecting a sample of the semen during intercourse are also available.

To get the most accurate result, two or three days’ abstinence is recommended before taking a sample of semen for analysis. In the case of longer periods of abstinence, the number of sperm cells may increase, but the percentage of sperm actively moving can reduce; shorter periods of abstinence can result in some decrease in the number of sperm cells present.

After the sample has been taken, it must be delivered to the laboratory within 30 to 45 minutes and, until it arrives there, kept as close to body temperature as possible.