The testes, epididymis, seminal tubes, prostate, and bulbourethral glands are among the four fractions of sperm. Since the composition of the tis differs with increasing fraction, combining all four fractions during ejaculation is needed to obtain a good semen specimen.
Composition of semen
- Spermatozoa: 5%
- Seminal Fluid: 60% – 70%
- Prostate fluid: 20% – 30%
- Bulbourethral glands: 5 %
Normal semen is transparent and has a musty smell. White blood cells (WBC) and disorders of the reproductive tract are shown by increased white turbidity. Before the semen examination, specimen cultivation is performed if necessary. WBCs must be separated from immature sperm before microscopic examination (spermatides). WBCs may be screened with the leukocyte esterase strip reagent check. RBCs (red blood cells) of different degrees of red coloration are rare. Oxidation of the sperm, the accumulation of samples following prolonged abstinence, and medication will all cause yellow shading.
Since a fresh semen specimen is coagulated and should be liquefied within 30 to 60 minutes of processing, recording the collecting time is critical for deciding semen liquefaction. Specimen testing can’t begin until the liquefaction process is complete. If the specimen still hasn’t liquified after 2 hours, proteolytic enzymes like alpha-chymotrypsin may be used to complete the sample. A lack of prostatic enzymes can cause liquefaction problems, which should be reported.
Semen usually ranges from 2 to 5 mL in length. Pouring the sample into a calibrated sterile graduated container in 0.1-mL intervals will be used to evaluate this. There is a reduction in volume after periods of extended abstinence. Reduced volume is more generally linked to infertility, and it may indicate irregular processing of one of the semen-producing organs, especially the seminal vesicles. It’s also essential to consider an incomplete specimen collection.
The viscosity of a specimen refers to its fluid consistency, which may be linked to its liquefaction. Materials that haven’t fully liquefied clump together due to their high viscosity. The typical semen specimen may be easily drawn into a pipette and discharged from the pipette in droplets that are not clumped or stringy. Regular droplets form a thin chain as they are separated from the pipette. Particularly viscous droplets with strings longer than 2 centimeters are known as this. The Viscosity Test can be rated from 0 (watery) to 4 (sticky) (gel-like). Viscosity may also be classified as minimal, average, or solid. Semen motility is hampered by higher viscosity and partial liquefaction.
With a pH range of 7.2 to 8.0, normal semen pH is alkaline. Infection is shown by elevated pH in the reproductive tract. Semen for pH testing should be added to the pH pad of a urinalysis reagent strip and the colour to compare to the manufacturer’s chart. It’s also possible to use pH test paper.
The total sperm count in a semen specimen is a reliable fertility predictor, even though only one spermatozoon fertilizes. Sperm concentrations of greater than 20 million per milliliter are considered standard, with borderline concentrations ranging from 10 to 20 million per milliliter. Multiplying the sperm content by the volume of the specimen yields the total eyaculate sperm count. A total sperm count of more than 40 million per ejaculate is considered natural (20 million per milliliter around 2 mL).
Since sperm transmitted to the cervix can push to the uterus, fallopian tubes, and ovum through the cervical mucosa, the presence of sperm capable of forward movement is critical for fertility. Historically, clinical laboratory monitoring of sperm motility was a retrospective test that involved studying an undiluted specimen and determining the proportion of motile sperm as well as the motility rate.
The World Health Organization uses an a, b, c, and d grading system. According to the interpretation, 50 percent or more of the sperm in categories a, b, and c should be mobile within 1 hour, or 25 percent or more should show gradual motility (a and b). A high proportion of immobile sperm and sperm clumps necessitates further investigation to determine sperm viability or sperm agglutinin concentration.
Sperm Motility Grading
|4.0||A||Rapid, Straight-line motility|
|3.0||B||Slower speed, some lateral movement|
|2.0||B||Slow forward progression, noticeable lateral movement|
|1.0||C||No forward progression|
Infertility is caused by both the presence of a sufficient number of nonmotile sperm and the development of sperm that is morphologically incapable of fertilization. The head, collar, midpiece, and tail shapes of sperm are all weighed. Low ovum penetration is associated with abnormalities in head morphology, while motility is impaired by anomalies in the back, midpiece, and tail.
The standard sperm has an oval-shaped head that is about 5 μm long by 3 μm wide and a flagellar neck that is about 45 μm thick. The acrosomal cap, which contains enzymes and is located at the tip of the head, is required for ovum penetration. Around half of the head and two-thirds of the sperm nucleus will be protected by the acrosomal shield. The head, which is attached to the tail, and the midpiece make up the neckpiece. Since it is enclosed by a mitochondrial sheath that provides the tail’s motility capacity, the midpiece is the thickest portion of the tail.
Normal sperm morphology values vary depending on the measuring method used, ranging from standard forms greater than 30% when using normal criteria to standard forms greater than 14% when using strict criteria.
Other Examinations of Semen
It is the main sugar in the sperm, and lower seminal fructose levels are linked to androgen deficiency. The sperm count and fructose levels have an inverse relationship. Insufficient testosterone or seminal insufficiency in the vesicles cause low fructose output. The resorcinol method is simple and inexpensive. The fructose in an acidic solution heated with resorcinol produces a red precipitate, according to this hypothesis. The fructose must be converted to hydroxymethyl furfural, and then condenses to form the true resorcinol precipitate.
Antibodies to Spermatozoa
Antibodies may be generated by either the male or female. The role of spermatozoal antibodies in infertility is now well understood in laboratory experiments, but there is still a lot of uncertainty about human spermatozoa. Agglutination tests for semen have been used in many clinical correlative experiments in the past. Franklin and Dukes used serum and semen in their procedure. After a four-hour incubation period at 37 ° C, the tests were viewed macroscopically (for sperm agglutination). Semen antibodies are often assessed by a variety of scientific testing companies.
- Concise Book of Medical Laboratory Technology Methods and Interpretations by Ramnik Sood
- Urinalysis and Body Fluids 5th Ed by Strasinger SK and Di Lorenzo MS