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Male partners with low sperm counts and/or low sperm
motility and/or abnormally shaped sperm and/or who have
antibodies against their own sperm, are classified as
"male factor" patients.
Specialists in male fertility are called Andrologists and
you may need to consult one prior to commencing IVF treatment.
Causes of Male Infertility
Male infertility is very common. About one in twenty men is
sub fertile and a male factor is present in half of all
infertile couples. About one third of all IVF procedures are
performed for male factor infertility. For most men the discovery
that they are infertile comes as a total surprise.
It must be remembered that the testis has two distinct
roles. The first is to produce the male sex hormone,
testosterone, which is important for providing sex drive,
erections, strong muscles and basically giving a man a general
feeling of well being. All these things can be described as
virility. The second function of the testis is to produce
millions of sperm everyday, a process which occurs inside the
approximately 150 metres of fine tubes in each testis. For most
infertile men it is only this process which is at fault and a
reduced number or poor quality of sperm are produced.
Why does this problem develop? We now believe that most cases
are genetic. In other words, these men are born without
the genetic information which would allow sperm production
to occur normally. At Monash University we have been researching
this issue and find that small pieces of the Y, or so called male
chromosome, missing in men with severe infertility. Presumably
these missing pieces of genetic information are the cause for
the poor sperm production. But we need much more research before
we can point to particular genes. Without that knowledge no
treatment for men to improve sperm counts is likely to become
available. IVF techniques offer hope now as they require very
much fewer normal sperm than does Nature.
In the remaining one third of infertile men, we can find
a likely cause for their infertility including:
Obstruction to the passage of sperm from the back of the
testis to the outside can result from blockage or absence
of the vas deferens. Common causes include, obviously,
vasectomy, but any history of injury, and other surgery or
sexually transmitted disease may be important.
Men can make antibodies to their sperm following vasectomy
or other trauma or infection. These antibodies are a common
cause of infertility and prevent sperm swimming or sticking
to the egg. The testis can be damaged by a wide number of
treatments including chemotherapy or X-Ray therapy.
Some men have difficulties obtaining an erection, or in
ejaculating due to a wide range of problems such as
diabetes, MS, or previous prostate surgery. In these
cases sperm can be found and used for IVF.
Rarely, a deficiency in the brain pituitary hormones may
result in low sperm counts. Its detection is important as
it is readily treated with hormone injections.
Finally there remains great controversy as to whether sperm
counts have declined worldwide. The alleged change is quite
small (about 15%) and no cause has been confidently identified.
In conclusion while the causes of infertility are uncertain
in many men, certain conditions can be identified and treated.
These facts make it essential that all infertile men have their
situation thoroughly investigated.
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