Sperm Analysis
With the help of a special algorithm, the sperm analyzer (sperm analyzer .casa) calculates the percentage of sperm in relation to the four-step motility and speed.
All calculations are performed using standard forms in accordance with the WHO 2021 6th edition requirements.
Kruger Morphology
Sperm morphology assessment. The value of assessing sperm morphology is not only in limited predictions regarding spontaneous pregnancy or IVF outcomes but also as diagnostic information about the functional condition of male reproductive organs, primarily the testes and epididymis.
Teratzoospermia Index (TZI)
Abnormal sperm:
- Lower fertilization potential;
- Increased DNA fragmentation;
- Increased frequency of structural chromosomal aberrations;
- Immature chromatin;
- Aneuploidy.
MAR Test (Anti-Sperm Antibodies)
The MAR test is used to diagnose the presence of an immunological factor in male infertility and can be identified even with normal sperm analysis results. It determines the number of sperm covered with anti-sperm antibodies (ACAT). These antibodies bind to the male gametes, suppressing their activity. They can also prevent sperm from binding to the zona pellucida and performing the acrosomal reaction.
DNA Fragmentation
DNA is a molecule consisting of two strands that contain genes. Under the influence of certain factors, the strands can break, forming fragments, and the integrity of the molecule is disrupted, damaging the genetic material of the cell.
Such damage significantly affects the ability of sperm to fertilize an egg. If fertilization occurs with a defective sperm, the likelihood of genetic disorders and congenital defects in the fetus increases, and there is a higher probability of miscarriage in the early stages. Numerous studies have revealed a direct correlation between a high DNA fragmentation index and unsuccessful IVF attempts.
It is recommended to take a DNA fragmentation test in the following cases:
- Infertility in a couple;
- Habitual miscarriage;
- Preparation for assisted reproductive technologies (ART), including IVF (in vitro fertilization), ICSI (intracytoplasmic sperm injection), intrauterine insemination;
- Failed IVF attempts;
- Abnormal sperm analysis results.
DNA fragmentation in sperm refers to the damage in the DNA chain contained in the head's nucleus. DNA breaks disrupt the integrity of the genetic information, reducing the quality of male gametes and making conception less likely.
Indications for evaluating DNA fragmentation in sperm include:
- Unexplained infertility (unknown genesis) with normal sperm analysis results;
- Habitual miscarriage in the spouse;
- Preparation for infertility treatment with ART methods;
- Failed IVF attempts in the past;
- Sperm cryopreservation;
- Older male age.
Detection of Nuclear Protein
A sperm cell with mature nuclear protein can be identified based on the levels of protamine and histones. A sperm cell may have either mature or immature nuclear protein. The result expressed as a percentage helps determine the success rate of fertilization.
Immature nuclear protein leads to DNA fragmentation and infertility associated with it.
During spermatogenesis, the chromatin of sperm undergoes a series of changes, including the conversion of histones into protamine I and II. Sperm chromatin with "mature nuclear protein" consists of 85% protamine I and II and 15% histone. Therefore, if histone levels are >15%, it indicates "immature nuclear protein."
Determining Sperm Viability
The integrity of the sperm membrane (both structural and functional) when it is questionable or insufficient may impair the fertilizing ability of the sperm (affecting motility, capacitation, acrosomal reaction, and sperm attachment to the extracellular membrane of the oocyte).
Membrane integrity is assessed using two tests:
- HOS (Functional integrity) - Sperm viability is characterized by the proportion of living sperm identified during the evaluation of their membrane integrity.
- Vitality (Structural integrity) - The vitality test is also a "cross-check of quality" to assess sperm motility.
Biochemical Semen Analysis
Alpha-glucosidase, zinc, citric acid, fructose – an analysis conducted to diagnose the concentration of substances affecting the formation, morphology, and fertilizing ability of male gametes.
- Alpha-glucosidase: An enzyme synthesized in the epididymis, normally present in semen. The activity level of alpha-glucosidase depends on the secretory function of the epididymis.
- Fructose: The main energy source for sperm. It is produced in the seminal vesicles under the influence of androgens and indicates the secretory function of the seminal vesicles.
- Zinc: Produced by the prostate gland. A decrease in its concentration in semen indicates reduced sperm quality, particularly affecting motility.
- Citric Acid: Affects the proper structure of sperm and their ability to penetrate the egg. A decrease in citric acid levels is observed in inflammatory processes in the urogenital tract as it is produced by the prostate gland.
Oxidative Stress in Sperm Analysis (ROS Test)
One of the factors that can reduce male fertility is the hyperproduction of reactive oxygen species (ROS), which leads to oxidative stress in sperm and consequently to male infertility.
When reactive oxygen species are present in excess in semen, they can initiate pathological changes in sperm, causing oxidative damage to cell membranes, proteins, and DNA.
How does stress affect sperm?
- Damage to membranes;
- DNA damage;
- Destruction of the natural protein coat;
- Damage to the tail;
- Acrosomal reaction.
Acrosomal Reaction
Infertility may be associated with a disruption of various stages of sperm-egg interaction: lack of normal acrosomal reaction and inability to penetrate the protective membrane of the oocyte (zona pellucida).
The acrosomal reaction is exocytosis, i.e., the release of proteolytic enzymes (acrosin, hyaluronidase, etc.) contained in the special organelle of the sperm – the acrosome.
The acrosomal reaction normally occurs when the sperm contacts the zona pellucida, but disruptions are rare.
There are three types of acrosomal reaction disorders:
- Premature acrosomal reaction before meeting the egg – excessive spontaneous reaction;
- Failure to release acrosin upon contact with the zona pellucida – insufficient induced reaction;
- Combined type of disorder – many sperm lose their acrosome before encountering the egg, and the remaining ones are unable to release enzymes upon contact with the zona pellucida.
The acrosomal reaction prevents fertilization of the egg.