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Arthur
Wisot, MD, F.A.C.O.G.(pictured) , David Meldrum, MD, F.A.C.O.G.
Board Certified Reproductive Endocrinologists,
Reproductive
Partners Medical Group,
Beverly Hills, Redondo Beach, Long Beach California
ICSI
(intracytoplasmic sperm injection) has revolutionized
IVF because it has allowed us to offer treatment to
men for whom no treatment was available. Not only
will it help couples in whom the male has just a few,
barely swimming sperm in the ejaculate, but thanks
to advanced techniques for aspirating sperm from the
ductal system and techniques to harvest sperm from
testicular biopsies, it can also aid men who ejaculate
no sperm.
ICSI sperm-harvesting techniques include MESA (microsurgical
epididymal sperm aspiration) and PESA (percutaneous
epididymal sperm aspiration), an office procedure
where sperm can be obtained by passing a tiny needle
through the skin into the epididymis. Testicular sperm
extraction (TESE) is also an office procedure, now
sometimes done with a large biopsy needle under local
anesthesia, rather than being done as a full surgical
biopsy, but sperm are not as reliably obtained.
This
new micromanipulation treatment, which was developed
in Belgium and introduced into the United States in
1993, evolved from previous attempts at micromanipulation
such as PZD (partial zona dissection) and SUZI (subzonal
insertion), which did not enjoy the success that ICSI
has attained.
The IVF cycle is conducted exactly in the manner described
above with a very few exceptions. After the eggs are
retrieved, instead of mixing the sperm with the egg,
the embryologist utilizes a thin glass pipette to
immobilize the sperm, sucks it up into the pipette,
and then injects it directly into the egg's cytoplasm.
Since the egg is the size of a pinpoint, it is a sophisticated
technique requiring a high-powered microscope, tiny
glass pipettes, and instruments that translate hand
movements into extremely fine movements of the pipettes.
In
the 2000 SART/CDC report, 47% of ART cases involved
ICSI. The success rate for IVF with ICSI is about
the same as for IVF, indicating that the manipulation
has very little effect on the egg. However, since
the female partners of these men are often reproductively
normal, there may be some small adverse effect, also
reflected in reports of slightly reduced embryo quality
with ICSI.
Most data indicates similar rates of congenital abnormalities
with the general population and IVF without ICSI,
although some reports suggest a minor increase of
chromosomal anomalies, many of which are related to
the man's genetics or his sperm, rather than the procedure
itself. Because of these concerns, prenatal genetic
testing with a fetal karyotype is suggested for ICSI
pregnancies. Recently, there have been concerns about
a higher rate of some very rare abnormalities which
may be associated with IVF and ICSI, specifically
Beckwith-Wiedemann syndrome which includes kidney
problems, low blood sugar and an increased risk of
childhood tumors.
In
a proportion of men (10 to 20 percent) with very low
or absent sperm in the ejaculate, the man may have
a chromosome defect or a genetic defect not visible
on routine chromosome analysis (Y chromosome microdeletion)
that could pass on a similar problem with infertility
to male offspring. Rarely, such a chromosome defect
could cause a serious abnormality in the offspring.
Therefore we suggest a pre-cycle karyotype for men
with fewer than 5-10 million sperm per ml in the ejaculate.
In men with congenital absence of the vas deferens,
one can assume the male is a carrier for cystic fibrosis
(CF). Since such men can have a mutation not screened
for in the standard CF panel, it is recommended to
test the female partner. If she is a carrier, the
couple could elect to have their embryos tested for
CF by testing a sample of amniotic fluid and aborting
a CF fetus, or now by preimplantation genetic diagnosis
where a cell is analyzed from each embryo and only
unaffected embryos are transferred.
Adapted from "Conceptions & Misconceptions:
The Informed Consumer's Guide through the Maze of
In Vitro Fertilization & Other Assisted Reproduction
Techniques" by Arthur L. Wisot M. D., FACOG and
David R. Meldrum M.D., FACOG, Hartley & Marks
Publishers, Point Roberts, WA (published Spring 2004)
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