from
the book How to Have a Baby: Overcoming Infertility
by Dr. Aniruddha Malpani, MD and Dr. Anjali Malpani,
MD.
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The Man with a Low Sperm Count
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The Latest Advance in Treating the Infertile Man (Page
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Table of Contents
What
is ICSI ?
How
can ICSI be used to treat men with a zero sperm count
( azoospermia) ?
What
is TESE ( testicular sperm extraction) ICSI ?
The introduction of Microinjection Technology
into the in vitro fertilization ( Fertilisation
Video ) laboratory has revolutionized our treatment
of the infertile man. Intracytoplasmic sperm injection,
or ICSI ( ICSI Video ) (pronounced
"eeksee"), is a new infertility treatment that uses
micromanipulation technology for treating male infertility.
What ICSI promises is the possibility for every man
to father his own baby - no matter what his medical
problem!
What is
ICSI ?
What exactly is ICSI? As the name suggests,
ICSI ( ICSI
Video ) is a technique in which a single sperm is
injected into the centre of the cytoplasm of the egg,
in order to achieve fertilization . While this may sound
very crude, ICSI allows the IVF laboratory to achieve
fertilization with very few sperm. The beauty of the
technique is that since the sperm is being injected
directly into the egg, all that is needed to achieve
fertilization ( Fertilisation
Video ) are live sperm - no matter how abnormal
these may appear to be. With ICSI the equation "1 egg
plus 1 sperm = 1 embryo" becomes possible!
ICSI is done in a superovulated cycle during which fertility
drugs (human menopausal gonadotropin - HMG- injections)
are administered to the wife to aid in the production
of multiple eggs, which are then removed under vaginal
ultrasound guidance as is done for IVF.
In normal circumstances, the egg is
surrounded by a cluster of cells known as the cumulus
corona cells, and this is called the oocyte cumulus
corona complex. These cumulus cells are removed by repeated
passage of the oocyte cumulus corona complex through
fine pipettes, and by treating them with a chemical
called hyaluronidase so that these cells are stripped
off. The denuded eggs are examined, and only mature
eggs (eggs in metaphase II, which have a polar body)
are used for ICSI.
Sperm is collected from the man, usually
through masturbation. For men with severe oligospermia,
we have found it useful to use sequential ejaculates.
Even though the first semen sample may not contain any
sperm, we often find motile sperm in the second ( or
even the third sample, for men with enough stamina !)
This maybe because the later samples contain "fresher"
sperm. Since these samples contain such few sperm, they
need to processed very carefully, so that the all the
sperm in the sample are recovered in the culture medium
, and can be used for ICSI.
For men with variable sperm counts,
which vary from zero to a few thousand, it may be helpful
to freeze a sample ( which contains sperm ) in advance.
For patients with azoospermia, sperm harvesting techniques
need to be used to retrieve the sperm. For men with
obstructive azoopsermia,( because of duct blockage or
absence of the vas deferens) , the simplest technique
is called PESA (percutaneous epididymal sperm aspiration),
in which the sperm is sucked out from the epididymis
by puncturing it with a fine needle. Occasionally, one
may have to use microsurgery to find epididymal sperm,
and this is called MESA (microepididymal sperm aspiration).
How
can ICSI be used to treat men with a zero sperm count
( azoospermia) ?
For patients with obstructive azoopsermia
in whom sperm cannot be found in the epididymis, it
is always possible to find sperm in the testis. The
easiest way to retrieve this is through TESA or testicular
sperm aspiration , in which the testicular tissue is
sucked out through a fine needle, under local anaesthesia.
The testicular tissue is placed in culture media and
sent to the lab, where it is processed. The sperm are
liberated from within the seminiferous tubules ( where
they are produced ) and are then dissected free from
the surrounding testicular tissue.
Using sperm from the epididymis and
testis for ICSI in order to treat patients with obstructive
azoospermia is logical, and thus conceptually easy to
understand. However, surprisingly, it is possible to
find sperm even in patients who have testicular failure
( nonobstructive azoospermia) - even in those men with
very small testes. The reason for this is that defects
in sperm production are "patchy"- they do not affect
the entire testis uniformly.
This means that even if sperm production
is absent in a certain area, there may be other areas
in the testis where sperm production would be normal
(this could be because the genetic defect that causes
abnormal spermatogenesis may be "leaky"). Since such
few sperm are needed for ICSI, we can find enough sperm
in over 50 per cent of patients with testicular failure
, even if their testes are as small as a peanut!
What is TESE
( testicular sperm extraction) ICSI ?
However, while finding sperm is quite
easy in men with obstructive azoospermia ( since their
testes are functioning normally ), patients with nonobstructive
azoospermia ( testicular failure) can be very challenging.
Often, sperm production in these men is sparse, and
multiple sites in the testis may need to be sampled
before being able to find sperm. This can be done by
performing mutiple tiny microbiopsies , and this is
called TESE or testicular sperm extraction. ( One of
our patients suggested that we call this procedure TSEICSI
- which stands for testicular sperm extraction with
ICSI, and pronounce it as "sexy"!) This can be done
through the needle, or as an open procedure performed
under direct vision through a tiny skin incision under
local anesthesia and sedation.
Finding sperm in the testicular tissue
can be a laborious process , depending on the degree
of sperm production, and for some men with partial testicular
failure, it can take upto 2-3 hours to find the sperm.
Also, testicular sperm are technically hard to work
with in the laboratory and only some IVF clinics have
the requisite expertise. For men with nonobstructive
azoopsermia, some clinics perform the TESE the day prior
to egg retrieval, because they believe culturing the
testicular tissue in the incubator for 24 hours helps
the sperm to acquire motility, which makes them easier
to work with. In case no sperm are found, either the
couple decides to cancel the egg retrieval and abandon
the cycle, or to go ahead with using donor sperm for
IVF, as a backup option.
In patients in whom surgery needs to
be performed in order to recover testicular or epididymal
sperm, it is now possible to freeze the excess sperm.
These sperm can then be thawed and used in future cycles
in needed, thus sparing the patient the need for repeated
surgery for sperm retrieval.
continued
. . .
Next page: Microinjection:
The Latest Advance in Treating the Infertile Man (Page
2)
Previous page:
The Man with a Low Sperm Count
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