Semen analysis is the assessment of the characteristics of a man’s semen and the sperm it carries. This examination is performed as part of the process to evaluate the man’s fertility, and is widely considered the most important diagnostic tool to investigate male problems with reproduction.
A semen analysis is commonly done for three reasons: to investigate infertility, to verify that a vasectomy was successful, and to test human donors for sperm donation. Thus, the most common parameters measured in this examination include sperm count, motility, morphology, and volume. Fructose level as well as pH are also commonly measured and used for clinical correlation. In the Philippines, semen analysis is available at several diagnostic centers, hospitals, and other health care providers.
Preparation for a semen analysis requires that the patient refrain from any sexual activity that results in ejaculation for 2 to 5 days prior to the examination. Abstinence from sexual intercourse for more than 1 to 2 weeks may result in sperm with less activity. Also, the use of alcohol, medicines, herbal supplements and recreational drugs must be disclosed to the physician conducting the test, since these factors may affect results.
The collection of a semen sample occurs through ejaculation into a sterile collection cup. While this may be accomplished through masturbation, some men may be uncomfortable with this practice or their religion may prohibit it entirely. Collection condoms, which are made from silicone or polyurethane, may be used as well, since latex is harmful to sperm. Some latex condoms also contain spermicidal chemicals, also incompatible with sperm survival. Additionally, sperm samples from collection condoms have been found to have higher total sperm counts, improved motility, and more normal sperm.
The following table summarizes normal findings for semen analysis:
|Sperm Concentration||At least 15,000,000/ml.|
|Total Sperm Count||At least 39,000,000 per ejaculate.|
|Motility||At least 50% (measured within 60 minutes of collection.|
|Vitality||At least 60%.|
|Morphology||At least 4% of sperm cells in the sample are normal.|
|Volume||At least 1.5 ml.|
|Fructose||At least 3mg/ml.|
|Liquefaction||Within 60 minutes of ejaculation.|
|White Blood Cells (WBC)||None.|
Sperm motility can be further specified according to motility grade, wherein the sperm cells are categorized into one of four categories:
- Grade a: progressive motility, swimming in a straight line.
- Grade b: progressive motility, but traveling in a curved or crooked path.
- Grade c: non-progressive motility, but tail movement is perceptible.
- Grade d: non-motile, non-moving sperm cells.
Semen analysis may be normal in men with abnormal sperm function, while men with poor results for semen analysis may successfully impregnate their partners. If the results from a man’s initial sample indicate subfertility (i.e. when two or more semen analyses have one or more variables below the 5th percentile), then two more semen assessments must be done for verification. The subsequent analyses must be done at least 2 to 4 weeks after each examination.