Male infertility is rarely discussed in society. This is partly because it is still somewhat of a taboo subject, but also because of a lack of knowledge about both its causes and effects. In fact, when a couple fails to conceive naturally, it is usually the woman who takes the first step to get tested. However, infertility affects both sexes equally.
At Dexeus Mujer, we have a unit specialising in male sexual and reproductive health and we offer heterosexual couples the option of a couple’s fertility assessment, which allows us to speed up the diagnosis when infertility problems are suspected.
For men, the first fertility test performed is a seminogram or semen analysis to assess the quality of the sperm. A consultation with the andrologist is also carried out to find out about the patient’s family history, medical history and other aspects of his lifestyle and health.
The more information available, the better, as the causes of male infertility can be multifactorial. Therefore, even if a semen analysis shows correct values, this does not mean that there is no infertility problem, and vice versa: a semen analysis with abnormal values does not always mean that a man is unable to have children. In this article, biologist Marta Ballester, head of the Andrology Laboratory at Dexeus Mujer, explains how sperm quality is assessed, what the key aspects are and why.
How is sperm quality assessed?
The World Health Organisation has established reference values for sperm motility, concentration and morphology, which have changed over the years. These values are based on studies carried out on large groups of individuals from different continents to be as representative as possible of the world population as a whole. However, they are only intended as a guide to standardise the results of analytical procedures and are not definitive. Techniques may vary from one laboratory to another, and the parameters examined may also vary. The final assessment must therefore always be made by a professional.
The seminogram or semen analysis is the basic test used to help determine a man’s fertility potential. This diagnostic test consists of a macroscopic and microscopic examination of the sperm.
Macroscopic analysis
This examination analyses the liquefaction time, viscosity, appearance, volume and pH of the semen.
Liquefaction: After ejaculation, the semen is in a coagulated state and must be liquefied for examination.
Viscosity: A viscous semen sample is a homogeneous mass whose consistency does not change over time. If the sample has a high viscosity, it may interfere with the analysis of other semen parameters or sperm selection techniques.
Appearance: Sometimes transient changes in colour or appearance may not be significant. However, if they persist, they may indicate the presence of a medical condition.
Volume: The analysis of ejaculate volume must be accurate as it is necessary to calculate the total number of spermatozoa present in the semen sample. Seminal plasma makes up 90% of the volume, while spermatozoa make up 10%. The ejaculate volume is considered normal if it is equal to or greater than 1.4 ml.
pH: The pH of the semen reflects the balance between the pH of the different secretions (acidic prostatic fluid and alkaline seminal vesicle fluid) and must be equal to or greater than 7.2 to be considered ideal.
Microscopic analysis
This analysis can be carried out under an optical microscope or using automated analysis systems. The sperm parameters analysed are as follows:
Concentration: The sperm concentration is considered normal if it is equal to or higher than 16 M/ml. If it is lower, it is called oligozoospermia, and the absence of spermatozoa in the ejaculate is called azoospermia.
Motility: Spermatozoa are classified into four categories according to their motility: type a (fast progressive), type b (slow progressive), type c (non-progressive) or type d (immotile). If the concentration of spermatozoa with progressive motility (a+b) is less than 30%, this is called asthenozoospermia.
Vitality: This parameter indicates the percentage of live spermatozoa in the ejaculate. It is important to note that the fact that spermatozoa are not motile does not mean that they are dead cells. If the ejaculate contains 25% to 30% of live and immotile forms, this could be due to a genetic flagellum problem, in which case motility cannot be improved by any treatment. On the other hand, a high percentage of immotile spermatozoa and dead cells could indicate an epididymal condition or an immunological reaction due to infection. If the percentage of live forms is less than 54%, this is called necrozoospermia.
Presence of leucocytes: Most ejaculates contain leucocytes or white blood cells. A normal ejaculate usually contains less than 1M/ml of leucocytes. If the number is higher, it may indicate the presence of an infection in the reproductive tract.
Morphology: This consists of analysing the size and shape of the head, neck and tail of the spermatozoa. The analysis of this parameter gives a prognostic value both for the possibility of a spontaneous pregnancy and for the results of assisted reproductive techniques (ART).
It also provides information about the functional status of the reproductive organs, such as the testicles and epididymis. If the percentage of normal forms is less than 4%, this is called teratozoospermia. Depending on the cause, this problem may be reversible (lifestyle, effects of certain drugs or infections) or irreversible (certain oncological treatments, genetic abnormalities or testicular diseases).
What happens if the sperm analysis is abnormal?
As we have already mentioned, there is no need to be discouraged, as an abnormal semen analysis does not always mean that you cannot become a father. There are currently medical and surgical treatments that can help improve the various parameters analysed. Healthy habits can improve not only morphology but also other sperm parameters such as concentration and motility. These include reducing stress, anxiety, smoking and alcohol consumption, eating a balanced diet and exercising regularly. There are also techniques that can be used to select and separate useful, good-quality spermatozoa from the rest and fertilise the egg in the laboratory. Sperm microinjection (IVF-ICSI) can be used, which involves inserting a spermatozoon directly into the oocyte
