THE MALE REPRODUCTIVE SYSTEM and SPERM DEFECTS
The sperm is the sex cell which is produced by the male. Sperms are capable
of active movement and they are suspended in a fluid called seminal fluid.
The male reproductive system is made up of the testes within which sperms
are produced and a rather complicated system of tubules through which
sperms are transported. The reproductive organs of the male are both inside
and outside the abdomen. The parts of the male reproductive system includeThe testes – which is the organ that produces the sperms
The duct ( tube ) system, which is made up of the epididymis and the
vas deferens which store and transport the sperms
The accessory glands, which include the seminal vesicles and prostate
gland which produce the fluid part of the semen which in turn provide
nourishment to the sperms.
The penis which is the male sexual organ
In an adult, the two testes produce and store millions of tiny sperm cells.
The testes are oval-shaped and grow to be about 5 cm x 3 cm in diameter.
They contain thin, highly coiled tubes called seminiferous tubules within
which sperms are produced. The testes also produce a hormone called
testosterone. Testosterone is the hormone that produces a deep voice, bigger
muscles, and body and facial hair, and it also stimulates the production of
sperm.
From the testes arise two coiled tubes called the epididymis. There is one
epididymis on each side. This is where sperms are stored temporarily after
they are produced from the testes. The two epididymis (one from each side)
join the vas deferens which is a muscular tube, one on each side. The vas
deferens receives the sperms from the epididymis.
The epididymis and the testes hang in a pouch-like structure outside the
abdomen called the scrotum. This bag of wrinkled skin helps to regulate the
temperature of testes, which need to be kept cooler than body temperature to
produce sperm. The scrotum changes size to maintain the right temperature.
When the body is cold, the scrotum shrinks and becomes tighter to hold in
body heat. When it's warm, the scrotum becomes larger and more relaxed to
get rid of extra heat.
As the vas deferens from both sides travel into the abdomen they are joined
by sac like structures called the seminal vesicles. The vas deferens and
seminal vesicles join together to form the ejaculatory ducts which empty the
sperms into the urethra. This is the final tube which carries sperms through
the penis to the outside.
The Sperm.
This is a picture of a mature sperm. It has a head which contains important
genetic material and that is the portion which enters the egg and fertilizes it.
The neck or midpiece provides energy for movement and the tail helps the
sperm to swim towards the egg.
How do we know if you have the correct number of sperms?
We do a test called a semen analysis. This is done after you have abstained
from intercourse for 2-3 days. We look at your semen sample under a
microscope to check if you have adequate numbers of sperms which move and
look normal. We say that your semen test is satisfactory if – you have more
than 15 million sperms, and if more than 50% move rapidly and more than
4% have a normal appearance.
Why should my sperm numbers, capacity to move and appearance be normal?
Abnormal sperm parameters can cause delay in conception and very low
numbers are associated with infertility.
How often are men the reason for infertility?
In about 40% of infertile couples the male is either the only reason or also
contributes to the infertility with the female.
Can a man have no sperms at all in his semen?
Yes. Some men have no sperms at all in their semen. This is called
azoospermia.
What are the reasons for reduced sperm numbers?
Often it is difficult to find a reason. These men are said to have idiopathic
defects- i.e: no cause identifiable.
The known causes of disordered sperm production are –
Infections of the testes ( mumps) and sexually transmitted infections
Certain medicines like – sulfasalizine (taken for bowel inflammation),
Phenothiazines ( taken for psychiatric illnesses) ,immunosuppressants
( taken after transplant surgery) and medicines used to treat cancer
Diabetes, thyroid and other endocrine defects.
Injury to the testes or operations to that area
Varicocele – this is an increase in the size of the veins inside the
scrotum making the testes warmer by increasing its blood flow. As
stated earlier, this can result in reduction in sperm production.
Being overweight, smoking and excess alcohol can reduce sperm
numbers and activity
Why do some men have no sperms in their semen?
This may be because of no production or may result because of blockage of the
duct system described above. Production may not occur when there are
certain hormone defects or when the man has an abnormal number of
chromosomes. The duct system may be blocked by damage due to infection or
a part of the duct may be absent from birth. Very often, we cannot identify a
reason for absent sperms
What is the treatment for sperm defects?
This depends on how severe the problem is.
With a slight reduction in sperms an IUI (intrauterine insemination) will be
advised. Here we do a ‘sperm preparation’. By this process, the dead and
inactive sperms and bacteria if present are removed and the good sperms are
made very active. These sperms are then placed within the woman’s uterus.
This procedure increases your chance of getting pregnant.
With very few sperms we may advise an IVF or an ICSI. For further
information please read the booklet on IVF and ICSI
What can be done when no sperms are present?
When no sperms are present in the semen, we will examine the testes to see
if they are of normal size. Then we usually advise a hormone test (FSH)
which will give us an idea as to whether you may have sperms within your
testes or not. Of course, the only test which can confirm this is a testicular
biopsy.
If sperms are present, we can do a small surgical procedure (read about
TESE and MESA in booklet) wherein we can remove them from the testes
and use them to fertilize the egg.
If however you cannot afford the above procedure or we do not find sperms in
your testes, you can choose to have donor sperms.
Will IVF with sperms taken from the testes or epididymis be as successful as
that taken from the semen?
Using sperms from the semen, nearly 75% of eggs are fertilized. This falls to
about 70% when sperms from the epididymis are used and to about 65%
when sperms from the testes are used. Though the chance is lesser, it is
important to remember that it is the only chance of you having your
biological child.
Are there any other reasons for male infertility?
Another reason may be sexual dysfunction. A few men may have a problem
with ejaculation and therefore be unable to have intercourse. Any doubts
regarding this can be discussed in detail with your doctor.
For further queries, please contact your specialist.
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