Sperm analysis
Male infertility is in most cases caused by sperm anomalies. Therefore, sperm analysis is the fundamental test in the assessment of fertility in men, especially in the view of the fact that in recent years the number of healthy sperm in semen, capable of fertilising woman’s eggs, has decreased considerably.
What are the causes of reduced sperm quality?
The lower count of progressive sperm in semen is primarily due to lifestyle and environmental factors, such as:
- toxins,
- radiation,
- obesity,
- general systemic diseases,
- genitourinary diseases.
Sperm analysis – the basic method of evaluating male fertility
The main parameters assessed in sperm analysis are sperm count in 1 ml of ejaculate and the number of viable spermatozoa (progressive motility). The test, known as computer-assisted seminogram, also allows to:
- detect anomalies of morphological disorders,
- assess the structure of spermatozoa,
- assess prostate secretion.
Abnormal results do not clearly indicate the cause of infertility, but confirm that there is a problem with fertility. Unfavourable diagnosis does not need to rule out the possibility of conception, as medicine allows to achieve pregnancy even with extremely poor sperm parameters.
When to perform sperm analysis and how to prepare for it?
Sperm analysis is recommended if after a year of regular sexual activity, the man’s partner does not get pregnant. Diagnostics of infertility may be started earlier in the presence of any known risk factors of male or female infertility.
The conditions in which sperm is stored are very important for the results, so it is preferable to provide a sample directly during the visit at the clinic. The ejaculate sample is collected by masturbation into a special, sterile container. If the sample is collected at home, it should be stored at 37oC, and kept away from light. The sample should be preferably delivered to the clinic within an hour after the ejaculation.
Sperm analysis should be conducted after 2 – 7 days of sexual abstinence. In this period the patient also should abstain from drinking alcohol. For accurate interpretation of the test results, the patient must inform the doctor about the history of diseases and medications taken within 3 months before the test.
Sperm analysis – diagnostics and standards
The most important parameter is the total motile (progressive) sperm count. It is determined based on two parameters (sperm count in 1ml of semen and progressive sperm rate). They are presented in bold in the table below.
| PARAMETER | WHO 2010 REFERENCE VALUE |
|---|---|
| Volume (ml) | 1.5 |
| Total sperm count (million) | 39 |
| Total sperm count (million/ml) | 15 |
| Motility (%) (progressive/non-progressive) | 40 |
| Progressive sperm (A+B) % | 32 |
| Viability (%) | 58 |
| pH | ≥7.2 |
| Normal morphology (%) | 4 |
| Leukocytes (million) | Less than 1 |
Computer-assisted sperm analysis
Computer assisted sperm analysis (CASA) allows for a very precise evaluation of sperm motility in the semen. The test analyses four parameters of sperm motility:
- VCL – curvilinear velocity (µm/s),
- VSL – straight-line velocity (µm/s),
- VAP – average path velocity,
- ALH – amplitude of lateral head displacement.
Why is computer-assisted sperm analysis a test worth taking?
Extended sperm analysis provides more precise results, offering more information regarding the chances of fathering a child. The benefits of this test include:
- more reliable prognosis regarding fertility – the CASA result correlates with the chance of fatherhood,
- higher precision than in the case of basic sperm analysis,
- objective results due to the standardised test conditions in every facility,
- greater usefulness of the motility parameters assessed using CASA compared to a standard sperm analysis.