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Assisted Laser Hatching
What is Assisted Hatching?
Couples may face difficulty and frustration after IVF and
ICSI treatments due to failure of successful implantation
of healthy looking embryos into the womb.
In general, the embryos are transferred back into
the womb on the second or third day, when they are in the
4 cell or 8 cell stage. Once they are placed back into the
womb, they keep on growing till day 5 (5 days after oocyte
retrieval). At this time the embryos are multicellular, and
differentiated into an inner cell mass and an outer cover
called the Trophectoderm. This embryo is called a Blastocyst.
The Blastocyst starts expanding and cracks open the cover
of the zona, and escapes out. This process is known as 'Hatching'.
In Assisted Hatching, a cut is given to the zona, when the
embryos are at 4 cell (day 2) or 6-8 cell (day 3) stage. These
embryos are placed back into the womb. The cut also called
Assisted Hatching, weakens the zona, and helps in the hatching
process. This in turn results in better pregnancy rates.
The cut can be made in three different ways:
1. Mechanical Hatching: In this
the embryo cover is slit open mechanically with the help of a thin
long drawn out glass needle. This is done with the help of a machine
called the Micromanipulator.
2. Chemical Hatching:
In this the zona is opened by touching it with a chemical
called Acid Tyrode Solution. This is also done with the aid
of the Micromanipulator.
3. Laser Hatching: This is the
latest method, introduced in the world in 1992. At present the Laser
beam is generated by an InGaSp Diode Laser. The zona is cut with the
Laser beam by simply pressing a button on the Laser machine. Many
babies have been born all over the world, following the introduction
of this technique.
Babies and Us Fertility Centre was the first unit in India to start
this technique in 1999. We have already completed more than 300 cycles,
with success rates as high as 30 %.
Which Patients benefit from Assisted Hatching?
The following group of patients are usually selected for the technique
of Assisted Hatching:
1. Women patients usually between
35-38 years of age
2. Patients in whom the zona thickness
is more than 15 microns
3. Patients who have had more
than one attempt at IVF/ICSI and have failed to become pregnant
4. Patients who have their extra
embryos frozen. The frozen thawed embryos are hatched before embryo
transfer
5. Patients who are undergoing
Pre-Implantation Genetic
Diagnosis
Which is the Best method of Hatching-mechanical,
chemical or Laser?
All the three methods give equivalent results in experienced hands.
However Laser Hatching is simple to perform, easy, accurate, and reproducible
and any embryologist can perform
it. Hence, it is the preferred method of choice. The biggest problem
with Laser Hatching is the cost of the machine, which is in the region
of US$40,000. In fact in India, there are very few ART Centres having
this facility. We at the Babies And Us Fertility Centre perform all
the techniques of Assisted Hatching. We are infact, the first unit
in India to perform this technique.
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