Causes of Male Infertility
Male infertility is mostly due to low
sperm concentration in semen, weak sperm motility (motion), increase in sperm
abnormal forms or due to low capability of fertilizing the ovum despite normal
concentration, motility and shape. Less commonly, infertility is due to
failure to deposit semen in the right part of the vagina such as the case with
impotence, curvature of the penis, hypospadias (abnormal position of the urine
outlet) or severe premature ejaculation.
Low sperm concentration (oligospermia)
or total absence of sperm (azoospermia) are due to either low activity of the
testis (functional) or due to occlusion of the sperm outlet
(Vas deferens) in which case infertility is
Occlusion of the vas deferens leads to infertility, since it is the tube
that conveys sperm to the urethra in the penis.
In such cases, semen may still be
ejaculated despite sperm being absent, since the seminal fluid is not produced
in the testis, but rather in the seminal
vesicles and prostate.. Obstruction just beyond the testis may still allow
seminal fluid to be ejaculated.
Obstruction may be on one side or both
sides. It may be partial or complete.
Obstruction occurs due to repeated
infections, mistakes at surgical procedures, or inborn congenital abnormalities.
Infections that reach the genital
system may be due to sexually transmitted
ddiseases such as gonorrhoea and
chlamydia, due to infection of urine commonly
caused by stones, where the infected urine forces itself down the vas deferens
upon straining. It can also spread from distant infections in the body such as
from the rectum.
Infection results in the formation of
pus, inflammation and fibrosis (solid tissues that are formed to repair wounds
and dead tissue). The accumulation of those results in obstruction of the vas.
Obstruction may result from mistakes
during surgery especially
surgery that is performed along the course of the vas deferens such as hernia
repair, varicocelectomy and testicular biopsy.
the author of this site has invented a surgical technique
for treating such cases. This technique is published and applied world-wide.
Inborn congenital abnormalities include total absence of the
vas deferens, whether
on one or both sides, or
presence of a spherical mass (cyst) at the point of union of both vasa
deferentia (the ejaculatory ducts).
Absence of he vas deferens may be associated with abnormalities in the kidney
and ureter, which is why imaging is
necessary to confirm their status.
Activity of the Testis
This is when the decrease in or absence
of sperm is due to weak spermatogenesis (sperm production). This may be caused
by any of the following:
This is a disease that affects veins of the testis. A vein is the
blood vessel that carries blood out of the testis, contrary to arteries, which
are the blood vessels that carry blood into the testis. The blood flows out of
the testis in the veins carrying waste products away, waste products such as
carbon dioxide, heat..etc.
In case of varicocele, the veins become
dilated and tortuous more than they should be. This
leads to stagnation (accumulation) of blood in the veins, and
cconsequently, accumulation of the aforementioned
waste products around the testis. The accumulation of those waste products
leads to damage of the testis and infertility.
However, they have no effect on sexual performance since they affect the
sensitive sperm-producing cells, and not the sturdy hormone-producing cells that
In the presence of a varicocele on one side, the other side
is affected as well due to the communication between
both testes. Most commonly, varicocele occurs either on both sides or on the
left side. It rarely occurs on the right side solely.
At the very
beginning, the testis produces sperm in a
concentration higher than normal and
morphology are normal.
Gradually, sperm production decreases both in quality and quantity, leading to
decrease in sperm concentration, motility, normal forms, and above all, a
decrease in fast forward motility and in the capability of fertilizing the ovum.
The latter does not show in a normal semen analysis. Therefore, a normal semen
in the presence of infertility and a varicocele may mean that sperm
fertilization capacity is abnormal. Eventually, in long standing larger grades
of varicocele, the testis becomes small and soft (atrophy), with no sperm
production. Varicocele may cause infertility regardless its grade, whether small
or large. Naturally, the larger the varicocele, the faster the deterioration is.
What causes varicocele? This is usually
a family predisposition where there is weakness of the body walls (congenital
weakness of the mesenchyme) affecting blood vessels (varicocele and leg varices)
or abdominal wall (hernia). In many cases, the cause is unknown, but the onset
of varicocele is aided by habitual straining such as in cases of long standing
constipation, long standing cough (smokers), weight lifting and prolonged
standing. Rarely, varicocele is caused by an abdominal mass. This is suspected
if varicocele occurs only on the right side.
What are the symptoms of varicocele? Usually there are no symptoms and
varicocele is discovered when infertility occurs. Sometimes, in large grades of
varicocele, there may be pain or heaviness, or there may be a whitish drop that
comes out of the penis following urination or defecation.
The testes develop inside the abdomen (upper back) while a fetus
is still in the uterus. It starts
making its way down to its normal position in the scrotum starting the 4th month
of pregnancy, and reaches it destination on the 8th month.
Sometimes, this descent fails and the
testis is trapped at any point along the course of its descent: Undescended
testes. The testis may become trapped inside the
abdomen, within the layers of the anterior wall of the abdomen (inguinal canal),
or at the neck of the scrotum.
The reason for failed descent may be
genetic (abnormality of the chromosomes) or mechanical (presence of a hernia
that traps the testis).
inside the abdomen leads to ooverheating of the testis,
resulting in infertility and possibly tumor formation. It is therefore that the
testis MUST be taken out of the abdomen whether by bringing it down to its
normal place if possible (orchiopexy) or
by total removal of the testis (orchiectomy)
to avoid the formation of tumors (if descent is not possible). Heat affects the
sensitive sperm-producing cells and not the sturdy hormone-producing cells.
Therefore infertility occurs but impotence and low verility do not occur.
Even if both testes have to be removes, impotence and
decreased masculinity will not occur (provided testosterone injections are used
every 4 months)
Usually the undescended testis
produces absolutely no sperm. Bringing down the testis to its normal place
(orchiopexy) in early childhood may help resuming sperm production. Orchiopexy
at adulthood is absolutely necessary for avoiding tumors, and may rarely help
with sperm production.
Diagnosis: the position of the testis
can sometimes be determined by
ultrasonography, CT or MRI. If they fail to demonstrate the testis,
laparoscopy is necessary to confirm its presence or absence.
Laparoscopy is also the way by which the
testis is brought down or removed.
Is a condition where the testis is
trapped in a position higher than normal, but can occasionally settle down to
its normal position. That is, it moves up and down. This condition does not
affect fertility unless the testis is pressed or hit at its higher position.
Surgical correction may be indicated for
cosmetic reasons. Hormonal treatment for this condition is controversial.
Hormonal treatment is based on the assumption that the hormones will increase
the size and weight of the testis, and thus being heavy it will not go up. This
is possible only in childhood, but has the disadvantages of possible mild
masculinization and shorter height of the child. Moreover, some adults have a
large and heavy testis that still goes up and down (retractile) despite its
These are inborn abnormalities due to defects in genes and or
Syndrome, where an extra "X"
chromosome lead to a total number of47 chromosomes instead of 46, and
infertility. The testis stops producing sperm and is small and form. The mixed
form of this condition (Mosaic form) may carry the possibility of sperm
production to a little extent, contrary to the absolute form.
Kallmann's Syndrome: where the
hypothalamus (part of the brain) does not produce the stimulating hormone (GnRH)
necessary for the activity of the pituitary gland,
that in turn stops producing the
hormones (FSH and LH) necessary for
stimulating the testis. Therefore the testis stops producing sperm and
testosterone, leading to infertility, impotence ad hypogonadism.
congenital abnormalities affect the sperm itself rather than affecting the
testis and affecting sperm production. Examples include absence of some of the
internal elements of the sperm tail and absence or disturbance of the
acrosomal cap necessary for fertilization.
A rise in prolactin or estrogen levels
results in infertility and impotence. Rise in prolactin level may sometimes be
due to a brain tumor. Rise in estrogen levels may be due to a tumor of the
testis. It is therefore nnecessary to perform
imaging investigations to check both.
A drop in testosterone level or FSH
level may produce infertility. This may be due to an abnormality of the
hypothalamus or pituitary, present in the brain, both of which produce hormones
that work together to activate the testis.
Some infections may damage the testis partially or totally. The most
famous is "Mumps", which is a virus that affects the
parotid gland and the testis at childhood.
Other infections include gonorrhoea and leprosy.
Accidental or habitual exposure to irradiation damages the testis unless
adequate safety measures are taken. Radiation include Xray, CT, MRI, atomic and
nuclear irradiation. Damage depends on the dose
received and on the duration. If the dose is not too high, the testis may return
to normal activity after a number of years depending on the dose.
It is therefore necessary to follow up
semen analysis as long as exposure is ongoing and to preserve sperm by
cryopreservation before exposure to
irradiation such as in tumor patients intending radiotherapy.
Some chemicals decrease testicular activity down to complete
arrest of sperm production, Those include chemotherapy for tumors, Petroleum
derivatives, Lead, insecticides, estrogenic chemicals..etc
It is therefore necessary to decrease
exposure as much as possible, to followup semen analysis as long as exposure is
ongoing, and to preserve sperm by
cryopreservation before exposure.
Excessive heat exposure over long periods leads to infertility. This is
possible in individuals working in the iron industry, next to ovens and those
driving heavy machinery emitting heat. It is again
necessary to followup semen analysis as long as exposure is ongoing
Accidents / Trauma
Trauma and accidents affecting the testis may lead to infertility.
Examples are direct kicks, blows, and falling astride an object. Trauma may lead
to perforation / rupture of the external wall of the testis (tunica
albuginea), with expulsion of the sperm producing tissue to the outside and
massive bleeding. It is necessary to consult a specialist as urgently,
especially if a swelling occurs, to determine the need for
surgical repair. The decision is made by
Torsion of the Testis
The testis receives blood vessels from
the body, some of which are feeding vessels pouring blood into the testis
(arteries), and others are draining vessels carrying
blood and waste products away from the testis (veins).
Torsion o the testis is a condition
when the testis rotates around its vertical axis, with
subsequent rotation and occlusion of the blood vessels, leading to death of the
testis within six hours.
Torsion leads to severe sudden pain. It
requires immediate consultation of a specialist to determine the necessity of
immediate surgical correction. Diagnosis is established by
ultrasonography. The latter measures the
blood flow in the painful testis in comparison to the normal one. If blood flow
is less in the painful one, the condition is diagnosed as torsion. If the flow
is higher, then it is a case of inflammation of the testis (epididymo-orchitis).
Epididymo-orchitis requires medical treatment, while torsion requires surgical
Some tumors affect the testis. Whether benign or malignant, they
lead to erosion and death of the sperm producing tissues. Some tumors secrete
feminine hormones such as estrogen.
Diagnosis of testicular tumors is by
ultrasonography and blood analysis. Blood analysis include hormones (that may
increase in some cases) and tumor markers (chemicals that increase in case of
tumor formation, including beta hCG and alkaline phosphatase)
Before treatment, it is necessary to
store sperm by cryopreservation since
some treatment modalities impair fertility (surgical excision, chemotherapy or
Abnormal Sperm Functions
Some diseases impair the capability of
sperm to fertilize the ovum such as by decreasing the dissolving enzymes in the
acrosome. Such conditions include varicocele
and infections. So despite the normal semen concentration, motility and normal
forms, the sperm still cannot fertilize the ovum. Some specific tests are
capable of diagnosing these conditions such as the "acrosin"
Antibodies are molecules produced by
the immune system to attack strangers such as microbes. Antibodies should not be
produced against one's own tissues. Unfortunately, this may occur in some
diseases called "autoimmune diseases".
Antisperm antibodies are
antibodies against the sperm They may be produced in the male or in the female's
cervical secretions to attack sperm. This happens whenever sperm leaves the
testis and is recognized in the blood by the immune system and is therefore
targeted. Sperms enter the blood in case of long standing obstruction
(accumulation and high pressure lead to microscopic ruptures and escape of
sperm) and in accidents with overt rupture of the testis. Antisperm antibodies
stop the sperm from moving and lead to agglutination (entangling of sperm tails)
Antisperm antibodies can be examined in semen, cervical mucous of the female and
in blood samples in both partners. The latter is of no clinical
significance. Examination is preferably by the indirect MAR test.
Microbes can decrease testicular activity down to total damage of the
testis if inflammation of the testis (epididymo-orchitis) occurs, ending in
atrophy (decrease in size and loss of function). This is
common with Mumps (air borne virus) gonorrhea (sexually transmitted bacteria)
and Ecoli (urinary bacteria).
On the other hand, mild infection can
cause infertility by occlusion (obstruction) of the
vas deferens, or by
decreasing sperm motility and capacity of fertilization.
Infection may spread to the testis from urine, blood, from having sex
with a lady who has infections, from toilet seats..etc.
Infection may or may not cause
symptoms. It may pass unnoticed but produce infertility.
In case there is pain in the testis, it
has to be differentiated from torsion of
Disorders of Deposition
Semen must be ejaculated at the deepest
point of the vagina. If this fails then there is a deposition disorder. Examples
curved penis, extreme
premature (rapid) ejaculation where semen is
ejaculated before the penis is inserted in the vagina.