Test
Tube Babies - IVF & GIFT
from
the book How to Have a Baby: Overcoming Infertility
by Dr. Aniruddha
Malpani, MD and Dr. Anjali Malpani, MD.
table
of contents·
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Embryo
Freezing
Since
most IVF programs superovulate patients to grow many eggs, there are
often many embryos. Since the risk of multiple pregnancies increases
with the number of embryos transferred (and in fact the law in the
UK prohibits the transfer of more than 3 embryos to reduce this risk),
many patients are left with "spare" or supernumerary embryos. These
can be discarded; or used for research. It is now also possible to
freeze these embryos and store them in liquid nitrogen. These stored
embryos can then be used later for the same patient - so that she
can have another embryo transfer cycle done without having to go through
superovulation and egg collection all over again. Moreover, since
this embryo transfer is done in a "natural" cycle ( when she is not
taking any hormone injections ) some doctors believe the receptivity
of the uterus to the embryos is better. For women with irregular menstrual
cycles, frozen embryo transfer can also be done in a " simulated natural
cycle", in which the endometrium is primed to maximize its receptivity
to the embryos by using exogenous estrogens and progesterone. Since
pregnancy rates with good-quality frozen-thawed embryos are as good
as with fresh embryos, we encourage all our patients to freeze and
store their supernumerary embryos, rather than discard them. Freezing
is very cost-effective, since transferring frozen-thawed embryos is
much less expensive than starting a new cycle, so that it serves as
a useful "insurance policy" in case pregnancy does not occur. However,
since it is worthwhile freezing only good quality embryos, the option
of freezing is a "bonus" which is available to only about 30% of all
IVF patients. About half of all embryos frozen survive the freezing
-thaw process. It is reassuring to know that the risk of defects is
not increased as a result of freezing. These frozen embryos can be
stored for as long as is needed - even for many years. When they are
in liquid nitrogen, at a temperature of -196 C, they are in a state
of suspended animation, and all metabolic activity at this low temperature
stops, so that a frozen embryo is like Sleeping Beauty !
Once
stored, embryos can be used by the couple during a later treatment
cycle, donated to another couple or removed from storage. These options
should only be undertaken after considerable discussion and written
consent from the parties concerned.

Fig
6. The Programmable embryo freezer. You can see the liquid nitrogen
vapours clearly.
Egg
freezing
While
we still cannot freeze unfertilised human oocytes efficiently, a new
technique called vitrification ( which uses ultra-rapid cooling together
with an increased concentration of cryoprotectants ) may allow us
to offer this option to our patients, in the future, allowing the
facility of egg storage and egg banking.
Analysing
a failed IVF cycle
If you
don’t get pregnant after your IVF attempt, you are likely to be very
disappointed and disheartened. However, remember that this is not
the end of the road - it’s just the beginning ! At the end of the
IVF cycle, you need to sit down with your doctor and analyse what
you learnt from it. Was the ovarian response good ? Was the endometrium
receptive ? Did fertilisation occur ? Why didn’t pregnancy occur (
though this is usually a question we still cannot answer !) Can you
repeat the same treatment, or do you need to make changes before going
in for your next attempt ? When can you go in for your next IVF cycle
? And even if you do not get pregnant, at least the fact that you
attempted IVF should give you peace of mind that you tried your best
, using the latest technology medical science has to offer.
The
second time around - the next IVF cycle
Most
doctors would advise you to wait for a month before starting a new
cycle. While it is medically possible to do the next cycle immediately,
most patients need a break to marshall their emotional strength before
starting again. Your doctor may need to modify your treatment, depending
upon an assessment of your previous cycle. For example, if the ovarian
response was poor, the doctor may advise you to increase the dose
of drugs used for superovulation. If fertilisation did not occur,
you may need to go in for microinjection ( ICSI). If the quality of
the embryos was poor, you may be advised to consider a ZIFT rather
than IVF. However, if the cycle was satisfactory, the doctor will
often advise you to repeat exactly the same treatment again - and
all that it may take to achieve your IVF success is time and another
attempt. Interestingly, we often find that couples going through a
second IVF cycle are much more relaxed and in control. This may be
because they are aware of all the medical and procedural minutiae,
and are better prepared for these; and also because they have had
a chance to establish a personal relationship with the medical team.
Also, since they have already faced failure the first time around,
many of them are much better able to cope with the stress of IVF,
since they are prepared for the worst. With today’s IVF technology,
we can confidently reassure any patient that we can help them to get
pregnant, provided they have inexhaustible resources of time, money
and energy !
GIFT
[continued
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