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A.R.T. For Male Factor Infertility
Intra-Cytoplasmic Sperm Injection (ICSI)
ICSI revolutionized the treatment of male factor infertility.
Technique:
Male factor infertility can be caused by various factors, such as mechanical or
congenital blockage of the tubes which transport the sperm thereby preventing
their release, inadequate sperm function due to chromosomal disorders, hormonal
factors and environmental factors. In certain cases, the cause of the problem
remains unknown.
ICSI can also be used in conjunction with IVF when the patient has history of
failed fertilization in previous conventional IVF cycle, or when the quality of
the sperm is considered to be too poor for a successful fertilization with
conventional IVF.
ICSI and conventional IVF both share the same protocol for
ovarian stimulation, follicular monitoring and egg collection. The sperm is
prepared on the same day of egg collection regardless it is a fresh or frozen
semen sample, and in same cases it involves surgically extracted sperm, such as
MESA, PESA, TESA or testicular biopsy.
ICSI is a technique allowing microinjection
of a single sperm into the egg. The embryologist selects a single live sperm,
immobilizes it before injects it directly into a healthy mature egg using a fine
pipette. The injected eggs are examined 16 – 18 hours later for evidence of
fertilization. The normally fertilized eggs are cultured and monitored until the
day of transfer. The day of embryo transferred can be 2, 3, 4 or 5 days after
the injection and only the best embryos (usually 3 embryos) will be transferred.
Success Rates (Pregnancy Rates) with ICSI:
As ICSI bypasses the zona pellucida (egg shell) and deposits the sperm directly into
the egg, ICSI results in higher fertilization rate and more embryos available for
transfer than conventional IVF. In general, the success rate for ICSI is as good as
or even better than conventional IVF.
Risk with ICSI:
There are concerns that ICSI is a rather invasive and new technology, it
may have additional risks associated with it. In March 1999, a retrospective
study involving 123 babies born in United Kingdom following ICSI was published
in British Medical Journal. In this study, no increase in major congenital
malformation in these babies was observed when compared to the normal
population.
Another risk in this treatment is multiple pregnancies. It not only causes
social and financial complications but is also associated with higher rates
of pregnancy loss and lower birth weight babies. Other mild risks are infection
and general anesthesia related complications.
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