|Routine Semen Analysis (RSA)|
The male partner will be asked to produce a semen sample to assess his fertilization potential. Samples should be collected either by masturbation or using a non-spermicidal condom e.g. Male Factor Pak (ZDL, Inc., Lexington, KY), after about 3-4 days of sexual abstinence. The reason for this time period is that too short intervals may not be sufficient to replenish the number of sperm, resulting in lower sperm counts. On the other hand, long abstinence periods could result in the accumulation of aged sperm, hence reflect poor sperm motility or quality. (See Reference)
The specimen will be assessed to see how many sperm are present, what percentage are motile and whether they are swimming straight (progressively). The shape of the sperm will also be evaluated. Other factors taken into consideration are the presence of epithelial (skin) cells, white blood cells, red blood cells and debris. Once all these assessments are done, the physician will have a overall picture of whether there is a problem, and if so, where it may be coming from.(See Reference)
The semen sample needs to be liquefied after ejaculation, which is caused/aided by an enzyme, fibrinolysin, secreted by the prostate. If liquefaction does not occur after 20-30 minutes, it could indicate some level of prostate dysfunction.
Semen should be slightly more viscous than water. When the specimen is highly viscous (stringy), this may be due to abnormal prostate function, frequent ejaculation, and/or the psychological state of the patient. This is not a direct cause of infertility, but can affect semen analysis determinations, such as concentration and motility.
The normal volume of an ejaculate after 3-5 days is 2-6mL. A low volume may indicate an obstruction due to infection of the genital tract or a congenital absence of the vas deferens. In cases, of retrograde ejaculation, low volume may also be apparent.
The color of semen is normally opaque and grey. In cases of infection, the semen may appear yellowish, and if bleeding is present, it may appear reddish or brownish. For samples with low sperm concentration or azoospermia, the sample may appear transparent and watery.
The pH of the normal ejaculate varies between 7.2-7.8. Values that fall out of this range may be indicative of an infection.
The normal concentration of sperm in an ejaculate should equal or exceed 20 million sperm/mL. If it does not, then this is termed Oligozoospermia.
Sperm need to be motile in order to travel through the female reproductive tract to get to the egg/oocyte, and then penetrate the outer covering of the egg. Various measurements to assess this include the percentage motile sperm, the percentage progressively motile sperm and the grade of motility. Normal values are 50% motile; less than this is termed Asthenozoospermia. Recent computer technology has allowed scientists to now measure the qualitative motility characteristics of sperm in terms of speed and straightness.
A supravital staining test is performed to distinguish live and dead sperm. Even though sperm are immotile, they are not necessarily dead sperm. The percentage of live sperm is usually higher than the percentage of sperm that is motile. If all the sperm are dead, it is termed Necrozoospermia.
Morphology:Normal sperm morphology has been shown to be predictive of IVF outcome/success. In general, sperm should have a smooth oval shaped head. The critical morphology as evaluated by KCRM uses a classification system that is slightly stricter in its criteria for a normal sperm than other systems. The criteria is based on the shape and appearance of post-coital sperm found in the internal os. Basically, the sperm should have a smooth oval head, with no defects in the neck or tail regions. Normal value is greater than 14% normal sperm.
|Isolation of High Quality Sperm|
In order for fertilization to occur, spermatozoa need to be separated from the seminal plasma. Since there is great diversity in semen profiles, especially among infertile men, each specimen undergoes a special tailor-made procedure to isolate the best sperm for ART. For this purpose, we have developed numerous innovative techniques depending on the quality of the specimen.
|Sperm Longevity Testing|
The duration of sperm motility is also an important indicator of sperm function and vitality. This is tested to ensure that sperm do not “die off”.
|Hypo-Osmotic Swelling test (HOS)|
HOS is used to test the integrity of the sperm cell membrane using the principle of osmotic differences. When normal sperm are placed in a hypoosmotic solution, water moves across the cell membrane into the sperm cell causing it to swell. If the membrane is damaged, then this transport of water will not occur. Thus, the percentage of swollen spermatozoa is the measure of intact membranes and hence sperm viability.(See Reference)
|Anti-sperm Antibody Testing|
These are antibodies produced by the immune system that mistake sperm for an invading substance and begins to attack them. The presence of anti-sperm antibodies has been shown to cause immobilization and agglutination of sperm, thereby preventing sperm from reaching the oocyte. Anti-sperm antibodies can be detected in serum, seminal plasma, cervical mucus and other reproductive tract fluids (tubal, follicular, uterine). It is estimated that 5-10% of male infertility is caused by antisperm antibodies and 10-15% of women with unexplained infertility have circulating sperm antibodies. (See Reference)
Retrograde ejaculation refers to the movement of seminal fluid backward into the bladder instead of forward through the urethra. This is caused by the inability of the bladder neck to close tightly enough during ejaculation. In men with retrograde ejaculation, the post-orgasm urine can be collected and assessed for the presence of sperm. If sperm are present, the high-quality sperm can be isolated and, if adequate, can be used for ART procedures. (See Reference)