Semen analysis

Definition

Semen analysis measures the amount and quality of a man's semen and sperm. Semen is the thick, white fluid released during ejaculation that contains sperm.

This test is sometimes called a sperm count.

Alternative Names

Male fertility test; Sperm count; Infertility - semen analysis

How the Test is Performed

You will need to provide a semen sample. Your health care provider will explain how to collect a sample.

Methods for collecting a sperm sample include:

• Masturbating into a sterile jar or cup
• Using a special condom during intercourse given to you by your health care provider

You should get the sample to the lab within 30 minutes. If the sample is collected at home, keep it in the inside pocket of your coat so that it will stay at body temperature while you are transporting it.

A laboratory specialist must look at the sample within 2 hours of the collection. The earlier the sample is analyzed, the more reliable the results. The following things will be evaluated:

• How the semen thickens into a solid and turns to liquid
• Fluid thickness, acidity, and sugar content
• Resistance to flow (viscosity)
• Movement of the sperm (motility)
• Number and structure of the sperm
• Volume of semen

How to Prepare for the Test

In order to have an adequate sperm count, do not have any sexual activity that causes ejaculation for 2 to 3 days before the test. However, this time should not be longer than 5 days, after which the quality can diminish.

How the Test will Feel

Talk to your provider if you are uncomfortable with how the sample is to be collected.

Why the Test is Performed

Semen analysis is one of the first tests done to evaluate a man's fertility. It can help determine if a problem in sperm production or quality of the sperm is causing infertility. About half of couples unable to have children have a male infertility problem.

The test may also be used after a vasectomy to make sure there are no sperm in the semen. This can confirm the success of the vasectomy.

The test may also be performed for the following condition:

• Klinefelter syndrome

Normal Results

A few of the common normal values are listed below.

• The normal volume varies from 1.5 to 5.0 milliliter per ejaculation.
• The sperm count varies from 20 to 150 million sperm per milliliter.
• At least 60% of the sperm should have a normal shape and show normal forward movement (motility).

Normal value ranges may vary slightly among different laboratories. Talk to your provider about the meaning of your specific test results.

The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.

It is not completely clear how these values and other results from a semen analysis should be interpreted. An abnormal result does not always mean there is a problem with a man's ability to have children.

What Abnormal Results Mean

Abnormal results may suggest a male infertility problem. For example, if the sperm count is very low or very high, a man may be less fertile. The acidity of the semen and the presence of white blood cells (suggesting infection) may affect fertility. Testing may reveal abnormal shapes or abnormal movements of the sperm.

However, there are many unknowns in male infertility. Further testing may be needed if abnormalities are found.

Many of these problems are treatable.

Risks

There are no risks.

Considerations

The following may affect a man's fertility:

• Alcohol
• Many recreational and prescription drugs
• Tobacco

References

Barak S, Baker HWG. Clinical management of male infertility. In: Jameson JL, De Groot LJ, de Kretser DM, et al. eds. Endocrinology: Adult and Pediatric. 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 141.

Niederberger CS. Male infertility. In: Wein AJ, Kavoussi LR, Partin AW, Peters CA, eds. Campbell-Walsh Urology. 11th ed. Philadelphia, PA: Elsevier; 2016:chap 24.