|
In
Vitro Fertilization (IVF)
What
is IVF?
In
vitro fertilization also called test-tube fertilization and often
shortened to IVF, is a treatment that has helped several thousand
couples achieve parenthood. 'In vitro' simply means in glass, and
refers to the fact that all test tubes were once glass.
'In
vitro fertilization' means fertilization outside the body. It is
a method, which has helped many women to have babies since 1978
when it was first used successfully. IVF is a method of assisted
reproduction in which a man's sperm and a woman's eggs are combined
in a culture dish. Once fertilisation is established, the resulting
embryos are left for 1-4 days to check that they are growing and
then transferred into the woman's womb. If the treatment has been
successful, one or more embryos will implant in the lining of the
uterus and each embryo will develop into a fetus and placenta.
The
first thing to mention is that IVF does not work every time. In
every unit in the world, IVF fails more than it succeeds.
Indication
For IVF- ET or ICSI
Tubal
disease
Endometriosis
Cervical factor
Male factor
Anovulatory infertility
Unexplained infertility
Immunological infertility
Donor eggs & Donor embryo
IVF
using donated eggs may be offered to women suffering premature menopause,
those whose eggs will not fertilize, those whose ovaries have been
removed or older women.
Chances
of success
The
average success rate for IVF is about 17% per treatment cycle, and
slightly less (about 12 %) for frozen embryo transfer. However,
your chances will very much depend on your own individual circumstances.
Before
starting treatment
The
first step before you start IVF is to discuss your fertility problem,
and talk over everything you are concerned about with the team who
will be treating you. Before IVF, tests are needed. Sometimes the
clinic may repeat the tests you have already had. Mostly, a semen
analysis, and most will perform blood tests to look for signs of
the hepatitis virus in you both and rubella.
There
are many considerations to be taken into account when deciding on
fertility treatment, and the doctor will offer you an opportunity
to talk through any issues and concerns either of you may have
Written
consent must be given before treatment begins. You should only give
your consent once you are satisfied that you understand what you
are agreeing to. Because the issues can be particularly personal
and far-reaching. You should feel that you have had the opportunity
to consider the implications of what it is you are being asked to
agree to.
What
does IVF involve?
Every
month women develop several eggs from one of their ovaries, but
usually only one is chosen by the body to be released into the fallopian
tubes. Most IVF units make women produce more that one egg, so that
they have a greater chance of collecting at least one which is healthy.
There are several ways egg production is stimulated. GMRH agonist
can be given either as a series of injections or by nasal spray.
Gonadotropin will act on the ovary to make it produce more eggs
than it would normally. They need to be given every day for about
eleven days. Many women prefer to give their own injections, or
ask their partners to give the, they find going to the IVF unit
or seeing their own doctor every day very stressful.
Egg
development and drugs:
Normally, every month a woman's ovaries begin to develop several
eggs but only one of these becomes fully mature. This egg is released
into the fallopian tube where it may be fertilised following intercourse.
IVF involves a small operation to collect eggs, and clinics prefer
to try to give the woman hormones ('stimulated cycle'). These generally
cause the ovaries to mature several eggs in one monthly cycle, which
can then be collected.
Drugs containing hormones usually be of 3
types:
- A
nasal spray or an injection given every day throughout the 28-day
cycle. These drugs suppress the hormones produced by a woman in
a normal menstrual cycle and enable greater control over when
the eggs are produced. These are GnRH agonists or antagonists
which your doctor will discuss with you.
- Injections
or tablets, which stimulates the ovaries. These are given so that
more than one egg develops, and are known as superovulatory drugs.
These drugs are gonadotropins, which will act on the ovary to
make it produce more eggs than it would normally. They need to
be given every day for about eleven days.
- Final
hormone injection is given which completes the maturing process.
Do
the drugs have side effects?
No
drug is absolutely safe and completely free of side-effects but
with the doses of drugs you are likely to notice few. With all fertility
drugs the biggest worries are that they will do their job too well
and produce an enormous response. This is called ovarian hyperstimulation
syndrome which is rarely the cause of anything more than some pain
and discomfort in the abdomen. However, in rare cases, it can become
more serious, and in some cases this may mean abandoning the treatment
for that cycle.
Egg
collection:
- Ultrasound
guided egg collection: The most common technique, this may be
done under a mild sedative or general anesthetic, and this is
usually a day-care procedure. A fine hollow needle is passed under
ultrasound guidance via the vagina and each egg is removed in
turn. The fluid from each follicle is sucked into tubes and examined
by an embryologist who looks for eggs. Each portion of fluid is
examined in turn and this is continued until every possible egg
has been collected.
- Laparoscopy:
This technique is rarely used nowadays but was the original method
of egg collection.
Fertilization:
The
eggs are also prepared and placed in an incubator. After about 3-6
hours, depending upon their maturity, the eggs and sperm will be
placed together in a specially prepared culture medium. It is inspected
the following day to see whether the sperm have fertilized the eggs.
The day after egg collection the embryologists can often tell if
fertilization has happened by examining the eggs. Not all eggs fertilize
properly, but only the healthy ones are used.
If
they have, the resulting embryos will be left to grow for a day
or two longer and some clinics also offer blastocyst culture and
transfer the embryos after 4-5 days.
Embryo
transfer:
The
embryologist will check that the embryos are developing satisfactorily
and may be transferred into the uterus by using a fine plastic tube
(a catheter).
This
procedure is quick, easy and simple. A fine plastic tube is passed
through the cervix, and the embryos put as high in the uterus as
possible. Since most embryos do not turn into babies, most IVF units
put more than one embryo into the womb. Putting three embryos into
the womb gives a better chance of a baby than one does but it also
gives a chance of more than one baby developing.
The
clinic will advise whether any remaining embryos are suitable for
freezing for treatment at a later date. Not all clinics are able
to offer freezing facilities.
What
happens next?
Usually
the clinician will prescribe further hormone injections or vaginal
pessaries to assist implantation. This will depend upon the levels
of hormones already in the blood and the type of drugs that have
already been given. Advice will also be given as to lifestyle pending
a pregnancy test will generally be performed two weeks after embryo
transfer.
If
the patient has become pregnant, the pregnancy test is normally
positive 15 days following egg collection. If the test is positive,
an ultrasound scan is performed three weeks later to assess the
status of the pregnancy.
Follow
up
If
the treatment is unsuccessful, the couple is encouraged to attend
for a follow-up consultation and they are offered counseling. At
this stage, the patients are usually aware that failure is more
common than success but nevertheless this is a very difficult fact
to accept and counselling is always available at this time.
Risks
of IVF
Some
women experience mild unpleasant symptoms as a reaction to the drugs,
but these are normally short-lived and are no cause for concern.
They may include hot flushes, feelings of depression and irritability,
headaches and restlessness at night.
Despite
careful monitoring, a small number of women may develop "Ovarian
Hyperstimulation Syndrome (OHSS). The majority of these women have
a mild or moderate form of over- response to the drugs, and complain
of pain and mild abdominal swelling. A fertility specialist should
monitor the condition, and in some cases the cycle may have to be
abandoned.
OTHER
OPTIONS ?
IUI
? IVF ? GIFT ? ICSI
? Blastocyst Transfer ? Assisted
Hatching? PGD ? Adoption
? DI ?
|