Semen Analysis - Everything about sperm & infertility (Part 2)

Sperm Motility:

(whether the sperm are moving well or not ). The quality of the sperm is often more significant than the count. Sperm motility is the ability to move. Sperm are of two types - those which swim, and those which don't. Remember that only those sperm which move forward fast are able to swim up to the egg and fertilise it - the others are of little use. Motility is graded from a to d, according to the World Health Organisation (WHO) Manual criteria , as follows. Grade a (fast progressive) sperm are those which swim forward fast in a straight line - like guided missiles. Grade b (slow progressive) sperm swim forward, but either in a curved or crooked line, or slowly (slow linear or non linear motility) . Grade c (nonprogressive) sperm move their tails, but do not move forward (local motility only). Grade d (immotile ) sperm do not move at all . Sperm of grade c and d are considered poor. Why do we worry about poor motility ? If motility is poor, this suggests that the testis is producing poor quality sperm and is not functioning properly - and this may mean that even the apparently normal motile sperm may not be able to fertilise the egg.

Sperm shape:

(whether the sperm are normally shaped or not - what is called their form or morphology. Ideally, a good sperm should have a regular oval head, with a connecting mid-piece and a long straight tail. If too many sperms are abnormally shaped (round heads; pin heads; very large heads; double heads; absent tails) this may mean the sperm are abnormal and will not be able to fertilise the egg. Many labs use Kruger "strict " criteria ( developed in South Africa ) for judging sperm normality. Only sperm which are "perfect" are considered to be normal. A normal sample should have at least 15% normal forms (which means that even upto 85% abnormal forms is considered to be acceptable!) Some men are infertile because most of their sperm are abnormally shaped . This is called teratozoospermia (terato=monster).

Sperm clumping or Agglutination:

Under the microscope, this is seen as the sperm sticking together to one another in bunches. This impairs sperm motility and prevents the sperm from swimming upto through the cervix towards the egg.

Putting it all together, one looks for the total number of "good" sperm in the sample - the product of the total count, the progressively motile sperm and the normally shaped sperm. This gives the progressively motile normal sperm count which is a crude index of the fertility potential of the sperm. Thus, for example, if a man has a total count of 40 million sperm per ml; of which 40% are progressively motile, and 60% are normally shaped; then his progressively motile normal sperm count is : 40 X 0.40 X 0.60 = 9.6 million sperm per ml. If the volume of the ejaculate is 3 ml, then the total motile sperm count in the entire sample is 9.6 X 3 = 28.8 million sperm.

Whether pus cells are present or not:

While a few white blood cells in the semen is normal, many pus cells suggest the presence of seminal infection. Many labs will mis-report round cells seen in the semen as being pus cells and doctors will then try to treat this "infection" with antibiotics !

Some labs use a computer to do the semen analysis. This is called CASA, (computer assisted semen analysis). While it may appear to be more reliable (because the test has been done "objectively" by a computer), there are still many controversies about its real value, since many of the technical details have not been standardised, and vary from lab to lab.

A normal sperm report is reassuring, and usually does not need to be repeated. If the semen analysis is normal, most doctors will not even need to examine the man, since this is then superfluous. However, remember that just because the sperm count and motility are in the normal range, this does not necessarily mean that the man is "fertile". Even if the sperm display normal motility, this does not always mean that they are capable of "working" and fertilising the egg. The only foolproof way of proving whether the sperm work is by doing IVF (in vitro fertilization) !

Overtreating a semen analysis report

Sadly, we see many men with completely normal semen analysis reports who have taken months of futile treatment ! Some doctors will "treat" a few pus cells in the semen with antibiotics - claiming that the pus cells suggest an infection ! Others will even try to treat a normal sperm count with medicines, claiming that their treatment will help to "boost" the sperm count and thus the man's fertility !

Azoospermia (no sperm in the semen)

About 10% of infertile men will have no sperm at all in the semen. This is called azoospermia . The conditions which cause azoospermia can be classified into 3 groups - pre-testicular, testicular and post-testicular. An example of azoospermia because of pretesticular disease is hypogonadotropic hypogonadism, where the testis does not produce sperm because of the absence of production of gonadotropins by the pituitary. Consequently, even though the testes are normal, no sperm are produced because of the absence of the needed hormonal stimulation. In testicular conditions, the testis does not produce sperm because of testicular failure (end-organ damage). In these men, the testicular damage is so severe that no sperm are found in the semen. This is also called non-obstructive azoospermia, and an example of this is Klinefelter's syndrome. In post-testicular conditions, even though sperm are being produced normally in the testes, the outflow passage is blocked (ductal obstruction or obstructive azoospermia)

If a semen report shows azoospermia, then it needs to be rechecked. The lab should be instructed to centrifuge the sample in order to look carefully for sperm. A close analysis of the report will often help the doctor to differentiate between non-obstructive and obstructive azoospermia . Thus, if the semen volume is low, the pH is acidic and the fructose is negative, then this is likely to be due to an obstruction at the level of the ejaculatory duct. If sperm precursor cells (immature sperm cells) are seen in the sample on careful microscopic examination, then this clearly means that the problem is not because of an obstruction.

We request men with azoospermia to provide a sequential ejaculate for semen analysis - two samples, produced 1-2 hours apart. Occasionally, in men with non-obstructive azoospermia, the second sample may show a few sperm, because it is "fresher".

A FSH level test in the blood ( as described in the next chapter) is also helpful in differentiating between obstruction and testicular failure. If the FSH level is high, it means the problem is testicular failure. If, on the other hand, the FSH level is normal, then a testis biopsy is needed to come to the correct diagnosis.

Rarely, some men will not be able to ejaculate at all. This is called aspermia , and their semen volume is zero. While this is sometimes because of a psychologic problem (because the man cannot achieve an orgasm inspite of being able to get an erection), the commonest reason for this is condition is retrograde ejaculation.

Poor sperm tests can result from incorrect semen collection technique, if the sample is not collected properly, or if the container is dirty too long a time delay between providing the sample and its testing in the laboratory too short an interval since the previous ejaculation recent systemic illness in the last 3 months (even a flu or a fever can temporarily depress sperm counts)

If the sperm test is abnormal, this will need to be repeated 3-4 times over a period of 3-6 months to confirm whether the abnormality is persistent or not . Don't jump to a conclusion based on just one report - remember that sperm counts do tend to vary on their own ! It takes six weeks for the testes to produce new sperm - which is why you need to wait before repeating the test. It also makes sense to repeat it from another laboratory to ensure that the report is valid.