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When all these three parts are examined cumulatively, they can
give you a clear idea of the semen, its viability and fertility.
For a semen
analysis, a fresh semen sample, not more than half an hour old
is needed, after sexual abstinence for at least 2 to 4 days. The
abstinence helps to concentrate the sperm in examination. The man is
asked to masturbate into a clean, wide mouthed bottle that is then
delivered to the laboratory. It can be quite stressful for some men
to produce a semen sample at demand. Men who have this problem can
and should ask for help.
The semen sample is kept at room
temperature in spotlessly clean container to avoid contamination.
After waiting for about 30 minutes post ejaculation, to allow the
semen to liquefy, the doctor will check the semen for the following
characteristics:
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The volume of the ejaculate
Normal volume of ejaculate in healthy men is about 2 to 6 ml. A
low volume (less than 1 ml) is often due to incomplete ejaculation
or spillage. Since the major portion of the ejaculate is produced
in the seminal vesicles, a low volume can relate to a problem with
seminal vesicle function. However, a very high volume of ejaculate
can also be a problem because this dilutes the total sperm
present. This decreases the sperm concentration and also your
chances of getting pregnant.
-
Semen viscosity
Usually after ejaculation the semen should liquefy again in about
30 minutes. This allows the sperm free motility. If the semen does
not liquefy or if it is very thick in consistency even after
liquefaction, this suggests an infection of the seminal vesicles
and prostate.
-
Semen pH
Normally the pH of semen is alkaline because of the seminal
vesicle secretion. An alkaline pH protects the sperm from the
acidity of the vaginal fluid. An acidic pH suggests problems with
seminal vesicle function. It is usually found in association with
a low volume of the ejaculate and the absence of fructose.
-
Presence of fructose.
Fructose is a sugar is produced by the seminal vesicles and
provides energy for sperm motility. Its absence suggests a block
in the male reproductive tract in ejaculatory duct.
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Visual examination of the
sample under the microscope.
Sperm count means the number of sperm present per ml of semen. If
the sample has less than 20 million sperm per ml, this is
considered to be a low sperm count. Less than 10 million is very
low. Some men who have no sperm at all and in their semen are said
to be azoospermic.
-
Sperm motility
The quality of the sperm is often more significant than the count.
Sperm motility is its ability to move. Remember that only those
sperm that move forward fast are able to swim up to the egg and
fertilize it. Motility is graded from a to d, according to the
World Health Organization (WHO) Manual criteria, as follows.
-
Grade a sperm are those that swim
forward fast in a straight line.
-
Grade b sperm swim forward, but
either in a curved or crooked line, or slowly.
-
Grade c sperm move their tails, but
do not move forward.
-
Grade d sperm do not move at all.
Sperm of grade c and d are considered poor.
-
Sperm form or morphology.
Ideally, a good sperm should have a regular oval head, with a
connecting mid-piece and a long straight tail. An abnormal sperm
is distorted in its shape. If too many sperm 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 fertilize the egg. A normal sample should have at least 15%
normal forms.
-
Sperm clumping or
agglutination.
Sperm clumping or agglutination means that many sperm stick
together in groups or clusters. This impairs sperm motility and
prevents the sperm from swimming up to through the cervix towards
the egg.
-
Presence or absence of pus
cells.
While a few white blood cells in the semen are normal, many pus
cells suggest the presence of seminal infection. This also can
affect the viability of the sperm.
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