Spermogram: How to interpret the findings of Semen Analysis
Semen analysis - the spermogram - is the cornerstone of laboratory assessment of male fertility and helps determine the severity of the condition. Detailed laboratory protocols have been published by the World Health Organization (WHO). The semen analysis provides information about the 4 basic characteristics of sperm quality: sperm volume, sperm concentration, motility, and morphology. Although methods for measuring sperm concentration and motility have changed little over the past two decades, estimation of sperm morphology has evolved significantly in recent years.
Actual reference values are not fully documented for the various parameters in semen analysis. The reference values we use are derived from WHO reports and the clinical literature. Results outside the reference range suggest the presence of male infertility and indicate the need for additional clinical and/or laboratory tests. It should be noted that the reference values for the various parameters of the semen analysis are not the same as the minimum values required for fertilization and that men with results in sperm analysis outside the reference range may be fertile. In contrast, patients having results within the range of reference values may be infertile.
All reference values and all laboratory techniques and procedures used to perform the Basic and Comprehensive Semen Analysis, as well as other biochemical and immunological tests for sperm and male fertility, are derived from the current guidelines of the WHO Laboratory manual of the examination and processing of human semen, 5th ed., 2010.
In the following paragraphs, we analyze the characteristics contained in semen analysis as we do in Diagnostiki Athinon.
Physicochemical and Macroscopic Characteristics in Spermogram
The physicochemical and macroscopic characteristics of the sperm included in the comprehensive and basic semen analysis include information on appearance, color, odor, liquefaction, viscosity, volume, pH, and other macroscopic observations that are important for the diagnosis of certain pathological conditions.
A normal sperm has a homogeneous, gray-opaque appearance or may appear less opaque if the concentration of spermatozoa is too low. Its color may be different when there are certain pathological conditions, e.g. be reddish-brown when there are red blood cells (hemospermia or hematospermia) or bright yellow in a man with jaundice or a man who takes certain vitamins or medications. The presence of red blood cells in the sperm may be the result of pathological conditions in the seminal vesicles or in the prostate.
The smell of semen is due to the oxidation of sperm and is normally characterized as the smell of bleach or boiled chestnut. Altered semen odor may be due to improper specimen collection containers or inflammation of the urogenital system.
Immediately after collection, the sperm is usually semi-fluid. Within minutes at room temperature, sperm usually begin to liquefy. The complete sample is usually liquefied within 15 minutes at room temperature, but it may take up to 60 minutes. Extension in liquefaction time (incomplete liquefaction) of sperm can be the result of pathological conditions in the seminal vesicles or prostate.
The semen pH reflects the balance between the pH values of the different secretions of the auxiliary glands, mainly the alkaline secretion of the seminal vesicles and the acidic secretion of the prostate. Normal sperm pH values range from 7.2 to 8.0. Sperm pH disturbances can be the result of abnormalities in the seminal vesicles or prostate and technical errors during the measurement (e.g. measurement of pH after a long period of time).
Sperm volume typically ranges between 2 and 4 ml. Volume reduction below 1.5 ml is characterized as hypospermia. Hypospermia can be due to both "technical" factors of sampling (such as the incomplete collection of the sample, leakage of the container after collection, etc.) as well as clinical reasons (such as abnormal conditions in the testicles, in the epididymis, in the seminal vesicles or in the prostate). Aspermia is the pathological condition in which no sperm is produced after "ejaculation". In this case, it is necessary to do further laboratory tests (post ejaculation urine analysis).
Sperm number in Spermogram
This parameter in semen analysis is usually expressed as the number of spermatozoa per ml of semen and is called the sperm concentration. The total number of sperm is their concentration multiplied by the volume of the sperm (in ml). The minimum sperm count considered within normal limits is 15 million / ml. Thus, a man at the lower end of the normal concentration and volume scale (1.5 ml) will have a total sperm count of 1.5 x 15 million = 22.5 million spermatozoa. The condition in which the sperm concentration is lower than 15 million / ml is called oligozoospermia, while low sperm volume, less than 1.5 ml is called hypospermia as mentioned below. As you can see, the total number of sperm is extremely high, especially when only one spermatozoon is needed to fertilize the egg. A low sperm count does not mean an inability to conceive. Lower sperm count means practically reduced chances of having children. When there is even one alive spermatozoon there is always the possibility of pregnancy.
Sperm motility in Spermogram
In semen analysis, motility refers to the number of spermatozoa that swim very fast (group a) and the number of sperm that swim slowly but forward (group b), expressed as a percentage. The sum of these two groups is the spermatozoa that can move forward (progressive motility) and the ones that can practically fertilize the egg. There are still some spermatozoa that swim in circles or rotate around their axis (group c) and are unlikely to be able to fertilize the egg. These spermatozoa are motile but without progressive motility. Sperm that remain immotile throughout the observation constitute group d. This group includes dead sperm and those that are alive but for various reasons remain immotile. The total number of sperm with progressive motility is a very essential feature of the potential of sperm for fertilization. The medical term used to describe poor sperm motility is asthenozoospermia.
The lowest value of the normal limit for total motility (total motile sperm) is 40% and for progressive motility is 32%. We have also maintained the reference value (> 25%) for group a (rapid progressive motility) according to the WHO reference values of the previous version because it has been shown in many research studies that the faster and more progressive the spermatozoa move in a semen sample, the higher the fertility rate. The numbers may seem a bit arbitrary and just based on statistics, but motility remains one of the most useful predictors for estimating fertility.
Sperm morphology in Spermogram
The morphology of the spermatozoa in the semen analysis report is mentioned very simply, in their shape. In order to be able to see the morphology of the sperm, a part of the sample is stained with special stains (such as Papanikolaou, Diff-Quik, or Wright-Giemsa) so that we can see the structure of the spermatozoa and classify each spermatozoon either as having physiological morphology or as having pathological morphology, according to very defined (strict) morphological criteria defined by the WHO. The World Health Organization (WHO) has set strict morphological criteria that determine the various morphological defects of sperm and these are usually grouped and referred to as the percentage of spermatozoa that present abnormalities of the head, neck, and tail. Also reported are spermatozoa that have very large parts of the cytoplasm (cytoplasmic droplets). These droplets are normal remnants of sperm maturation and when they are too large they can impede sperm motility and function. The overall result very often shows that only a very small percentage of spermatozoa are characterized as normal. In fact, a semen sample is considered morphologically normal in semen analysis if only 5% of the spermatozoa meet the strict morphology criteria. In other words, in a semen sample, 95% of the spermatozoa may present with abnormal morphology and remain within normal limits.
The definitions of the WHO morphology are very specific so that the specific qualitative characteristic of the sperm is accurately recorded. The presence of an increased number of spermatozoa (> 95%) with pathological morphology is known as teratozoospermia. The TeratoZoospermia Index (TZI) refers to the average morphological abnormalities per spermatozoon. The higher this index, the more abnormalities there are in 1 spermatozoon (each spermatozoon can have not only 1 morphological abnormality but 2, 3, or even 4 sometimes). It is quite possible that some of the sperm that are morphologically abnormal may function normally, but even so, an average semen sample containing 100 million spermatozoa in total and 94% being morphologically abnormal, 6 million normal spermatozoa are still available!
The WHO criteria for assessing sperm morphology are similar to those of Kruger (Tygerberg). When these criteria are applied to assess sperm morphology, relatively few spermatozoa are classified as having a normal morphology, even in sperm from fertile males.
From a clinical point of view, the morphological alterations of the sperm provide information about their functionality. For example, if there are many spermatozoa with defects in the tail, their motility may be affected as they move through the cervical mucus.
Vitality of spermatozoa in the Spermogram
Vitality refers to the proportion of sperm that are dead or alive. Normally all swimming spermatozoa are alive, but it is not possible to distinguish live from dead sperm when they are immotile. This is achieved by special staining that has the property of not being able to enter (and stain) living cells while being able to enter dead cells by staining them.
Results are reported as a percentage of live and dead spermatozoa. The minimum vitality that is considered normal is 58% and the medical term for lower values is partial necrospermia (total necrospermia is if all spermatozoa are dead). Examination of sperm vitality in semen analysis is especially important in situations where there is very low sperm motility.
Other Cells in Spermogram
There may be some other cells in the semen sample, mainly white blood cells (leukocytes), red blood cells (erythrocytes), or immature sperm cells (spermatids). The presence of red blood cells in the sperm as already mentioned is called hemospermia and usually indicates an infection or trauma. The presence of an increased number of leukocytes in the sperm (leukocytospermia) may indicate inflammation of the auxiliary glands, inflammations that may affect the motility of sperm. In addition, these white blood cells produce oxygen free radicals and cytokines, molecules that lead, among other things, to increased fragmentation of sperm DNA. Leukocytospermia contributes to male infertility. White blood cells are often difficult to distinguish from immature sperm. Both of these cell types (leukocytes and immature sperm cells) are collectively referred to as round cells and can be identified separately by special techniques that detect an enzyme called peroxidase. Immature sperm cells are negative for peroxidase while leukocytes are positive for peroxidase. In Comprehensive Semen Analysis, the two cell types are detected separately while in the Basic Semen Analysis the round cells are counted as a whole.
Automatic Analyzer Results in Spermogram
Each Comprehensive Semen Analysis is accompanied by the test of an automatic sperm analyzer. The characteristics of the sperm that are checked with the analyzer are Concentration, Progressive Motility, Morphology, Concentration of Motile Sperm, Concentration of Functional Sperm, and the calculation of an Index which refers to the combination of motile and morphologically normal sperm). The results of the automatic analyzer in the spermogram classify the semen sample based on its reference values for each parameter separately as Good - Medium - Poor.
The report of the automatic analyzer is presented only for comparative reasons and may not be identical to the overall picture of the semen analysis, as it has been performed from the study of the sample by our medical doctor.
Conclusion and Evaluation of Spermogram Results
The spermogram is completed with the conclusion of the responsible Medical Doctor who performed the examination of the semen sample. The final results are not just numbers and measurements. They represent a medical reality and a patient seeking a solution to his problem.
In semen analysis - spermogram, there may be unexpected findings that need further investigation. When spermatozoa are absent (azoospermia), for example, fructose may need to be measured to determine if it is the result of a congenital anomaly or an obstruction. If the fructose concentration is low there may be congenital abnormalities or obstruction of the seminal vesicles or other points of the excretory system.
When motile sperm stick to each other (agglutinations), it may indicate the presence of antibodies and should be investigated further. The presence of microbes and / or leukocytes should also be further investigated for the presence of inflammation in the urogenital system.
At Diagnostiki Athinon, a completed Microbiological Laboratory, we will recommend and are able to perform accurately and reliably all the laboratory tests that may be needed in order to fully investigate the problem of male infertility. If we find the causes we can solve the problem.
Diagnostiki Athinon is "The Specialized Laboratory for the Investigation of Male Fertility".
SpermaScan® is a trademark of Diagnostiki Athinon that includes all diagnostic and research tests related to the investigation of male fertility.
