A semen analysis (plural: semen analyses), also called seminogram or spermiogram, evaluates certain characteristics of a male's semen and the spermatozoon contained therein.
Semen analysis is a complex test that should be performed in andrology laboratories by experienced technicians with quality control and validation of test systems. A routine semen analysis should include: physical characteristics of semen (color, odor, pH, viscosity and liquefaction), volume, concentration, morphology and sperm motility and progression. To provide a correct result it is necessary to perform at least two, preferably three, separate seminal analyses with an interval between them of seven days to three months.
The techniques and criteria used to analyze semen samples are based on the WHO manual for the examination of human semen and sperm-cervical mucus interaction published in 2021.
Occasionally a man will have a semen analysis done as part of routine pre-pregnancy testing. At the laboratory level this is rare, as most healthcare providers will not test the semen and sperm unless specifically requested or there is a strong suspicion of a pathology in one of these areas discovered during the medical history or during the physical examination. Such testing is very expensive and time-consuming, and in the U.S. is unlikely to be covered by insurance. In other countries, such as Germany, the testing is covered by all insurances.
There are some situations that necessitate alternative collection methods, such as retrograde ejaculation, neurological injury or psychological inhibition. Depending on the situation, specialized condoms, electrostimulation or vibrostimulation might be used.
Chips for home use are emerging that can give an accurate estimation of sperm count after three samples taken on different days. Such a chip may measure the concentration of sperm in a semen sample against a control liquid filled with polystyrene beads. New Chip Provides Cheap At-Home Sperm Counting By Stuart Fox Posted 01.26.2010 in Popular Science
A more specified measure is motility grade, where the total motility(PR+NP) and immotile.
Progressively motile- Sperm moving in forward direction is Progressively Motile
Non progressively Motile-Those sperms are moving circular motion are Non Progressively Motile
Immotile- Those sperms are fail to move or dead sperms.
The total motility reference of 40% can be divided in a 32% of progressive motility and 8% of motility in situ.
Semen samples which have more than 30% progressive motility are considered as normozoospermia. Samples below that value are classified as asthenozoospermia regarding the WHO criteria.
Normal sperm morphology is hard to classify because of lack of objectivity and variations in interpretation, for instance. In order to classify spermatozoa as normal or abnormal, the different parts should be considered. Sperm has a head, a midpiece and a tail.
Firstly, the head should be oval-shaped, smooth and with a regular outline. What is more, the acrosomal region should comprise the 40–70% area of the head, be defined and not contain large vacuoles. The amount of vacuoles should not excess the 20% of the head's area. It should be 4–5 μm long and a width of 2,5–3,5 μm.
Secondly, the midpiece and the neck should be regular, with a maximal width of 1 μm and a length of 7–8 μm. The axis of the midpiece should be aligned with the major axis of the head.
Finally, the tail should be thinner than the midpiece and have a length of 45 μm approximately and a constant diameter along its length. It is important that it is not rolled up.
Since abnormalities are frequently mixed, the teratozoospermia index (TZI) is really helpful. This index is the mean number of abnormalities per abnormal sperm. To calculate it, 200 spermatozoa are counted (this is a good number). From this number, the abnormalities in head, midpiece and tail are counted, as well as the total abnormal spermatozoa. Once that task has been done, the TZI is calculated like this:
TZI= (h+m+t)/x
Another interesting index is the sperm deformity index (SDI), which is calculated the same way as the TZI, but instead of dividing by the number of abnormal spermatozoa, the division is by the total number of spermatozoa counted.
The TZI takes values from 1 (only one abnormality per sperm) to 3 (each sperm has the three types of abnormalities).
Morphology is a predictor of success in fertilizing oocytes during in vitro fertilization.
Up to 10% of all spermatozoa have observable defects and as such are disadvantaged in terms of fertilising an oocyte.
Also, sperm cells with tail-tip swelling patterns generally have lower frequency of aneuploidy.
The human ejaculate is mostly composed of water, 96 to 98% of semen is water. One way of ensuring that a man produces more ejaculate is to drink more liquids. Men also produce more seminal fluid after lengthy sexual stimulation and arousal. Reducing the frequency of sex and masturbation helps increase semen volume. Sexually transmitted diseases also affect the production of semen. Men who are infected with the human immunodeficiency virus (HIV) produce lower semen volume.
The volume of semen may also be increased, a condition known as hyperspermia. A volume greater than 6mL may indicate Prostate inflammation. When there's no volume, the condition is named as aspermia, which could be caused by retrograde ejaculation, anatomical or neurological diseases or anti-hypertensive drugs.
Semen that has a deep yellow colour or is greenish in appearance may be due to medication. Brown semen is mainly a result of infection and inflammation of the prostate gland, urethra, epididymis and seminal vesicles. Other causes of unusual semen colour include sexually transmitted infections such as gonorrhea and chlamydia, genital surgery and injury to the male sex organs.
With a straw or a vial volume of 0.5 milliliter, the general guideline is that, for intracervical insemination (ICI), straws or vials making a total of 20 million motile spermatozoa in total is recommended. This is equal to 8 straws or vials 0.5 mL with MOT5, or 2 straws or vials of MOT20. For intrauterine insemination (IUI), 1–2 MOT5 straws or vials is regarded sufficient. In WHO terms, it is thus recommended to use approximately 20 million grade a+b sperm in ICI, and 2 million grade a+b in IUI.
Use of approximately 20 million sperm of motility grade c or d in ICI, and 5 million ones in IUI may be an approximate recommendation.
Compared to samples obtained from masturbation, semen samples from collection condoms have higher total sperm counts, sperm motility, and percentage of sperm with normal morphology . For this reason, they are believed to give more accurate results when used for semen analysis.
If the results from a man's first sample are subfertile, they must be verified with at least two more analyses. At least two to four weeks must be allowed between each analysis.Toni Weschler (2006). Taking Charge of Your Fertility (10th Anniversary ed.). New York: Collins. . Results for a single man may have a large amount of natural variation over time, meaning a single sample may not be representative of a man's average semen characteristics. In addition, sperm physiologist Joanna Ellington believes that the stress of producing an ejaculate sample for examination, often in an unfamiliar setting and without any lubrication (most lubricants are somewhat harmful to sperm), may explain why men's first samples often show poor results while later samples show normal results.
A man may prefer to produce his sample at home rather than at the clinic. The site of semen collection does not affect the results of a semen analysis.. If produced at home the sample should be kept as close to body temperature as possible as exposure to cold or warm conditions can affect sperm motility
Computer assisted semen analysis ( CASA) is a catch-all phrase for automatic or semi-automatic semen analysis techniques. Most systems are based on image analysis, but alternative methods exist such as tracking cell movement on a digitizing tablet. Computer-assisted techniques are most-often used for the assessment of sperm concentration and mobility characteristics, such as velocity and linear velocity. Nowadays, there are CASA systems, based on image analysis and using new techniques, with near perfect results, and doing full analysis in a few seconds. With some techniques, sperm concentration and motility measurements are at least as reliable as current manual methods.Testing of Accubead in:
Raman spectroscopy has made progress in its ability to perform characterization, identification and localization of sperm nuclear DNA damage.
Semen Fructose Test has made progress in its ability to perform characterization, identification and localization of sperm nuclear DNA damage.
Reasons for testing
Relation to fertility
Collection methods
Parameters
Sperm count
Others advocate obtaining a second semen analysis to verify the counts are not increasing (as can happen with re-canalization) and others still may perform a repeat vasectomy for this situation.
Sperm motility
Sperm morphology
Motile sperm organelle morphology examination
Semen volume
Appearance
Fructose level
pH
Liquefaction
Viscosity
MOT
DNA damage
Total motile spermatozoa
Others
Abnormalities
Factors that influence results
Measurement methods
See also
Further reading
External links
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