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Chapter 25d
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 on next page]
by Dr. Aniruddha Malpani, MD and Dr. Anjali Malpani, MD.
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