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How successful is in vitro fertilization?
The chances of successful pregnancy with in vitro fertilization is
directly related to the age of the woman who provides the egg. Most
in vitro fertilization programs divide up their success rates according
to age.
For example, clinics will report pregnancy rates for women under and
over the age of 35 years. There is certainly a deterioration in the
quality of
eggs from the mid-thirties onwards. Some clinics divide up success
rates further, and specifically report pregnancy rates for women
between the ages
of 35 and 37, 38 and 39, 39 to 42, and then over the age of 42. Our
clinic is still young, however, our clinical pregnancy rates in year
2003 for women
under the age of 35 was 67%, with a fall-off in pregnancy rates for
women between the ages of 36 and 44 years.
Success rates are further influenced by the number and quality of eggs
that are retrieved from the ovary, by the quality of the uterus, including
the endometrial lining and the presence or absence of uterine fibroids,
by the number of embryos that are transferred and also by maternal
weight. Elegant studies have shown very carefully that obesity
will significantly affect the chances of pregnancy as well as the risk
of miscarriage.
Obviously, there are patients in all categories who may have
poorer chances of pregnancy success than others of equivalent
age. Such
patients would include those with a history of previous in vitro
fertilization failures, as well as those with limited ovarian
reserve and other
pelvic
factors
such as uterine
fibroids and tubal disease or endometriosis. This is why it is
so difficult to draw conclusions from statistics provided by
various clinics.
There
are indeed some clinics who will not take on women who are obviously
at low risk
for for successful pregnancy – for fear that a lack of success
could adversely skew statistics.

What are my risks related to in vitro fertilization?
The risks may be divided into various categories:
- The risks related to ovulation induction (the use of fertility drugs).
- The risks related to the surgical retrieval of eggs.
- The subsequent risk of pregnancy – specifically of multiple pregnancy.
One of the commonest serious side effects from using fertility drugs is a
condition known as ovarian hyperstimulation syndrome (OHSS). Ovarian hyperstimulation
syndrome becomes a risk in women who develop more than 20 follicles in response
to the fertility drugs. In these circumstances the blood estrogen levels
are often very high, and this combination causes OHSS. It is not a very well
understood condition, however, this combination of events tends to lead to
a metabolic imbalance which increases the risk of thrombosis, as well as
having an effect on body tissue permeability, which results in collection
of fluids in the abdomen and chest. The best form of management is prevention.
Women at particularly increased risk for this condition are women with a
condition known as polycystic ovarian syndrome, or younger women with a history
of infrequent or longer than average menstrual cycles.
Common symptoms of early OHSS include abdominal discomfort, bloating
and nausea. More severe symptoms would include a decrease in urine output
and difficulty breathing. Ways to avoid this syndrome are to reduce the medication
dosage in patients at risk, and to follow the development of the follicles
very carefully. If too many follicles are developing, a process called “coasting” may
be done, during which time no further fertility drugs are given and the estrogen
levels are monitored until they start declining. Only then would an egg retrieval
be performed – thereby reducing the risk of OHSS. Most cases of OHSS
are mild, though specific management may include surgically draining the
fluid from the abdomen (by using a fine needle), careful fluid balance and
the use of blood-thinners.
During egg retrieval, a needle is passed under ultrasound guidance
through the vagina into the ovaries. The follicles are then aspirated, the
fluid collected and the eggs isolated. We use a combination of local anesthetic
and intravenous sedation during the procedure. Like any surgical procedure
there are risks of bleeding, infection, and injury to structures around the
ovary. Such structures include bowel, the ureters and bladder. Prophylactic
antibiotics are always used, and the risk of infection, bleeding and organ
injury is, in fact, very low.
The main pregnancy risks related specifically to in vitro fertilization
are those associated with multiple pregnancies. Our motto is “As Many
Babies As You Want, Though Preferably One At A Time”. However, we have
a responsibility to maximize chances of pregnancy, keeping in mind
a desire to keep the risk of multiple pregnancy to a minimum. As a rule of
thumb,
we at Victoria Fertility Centre will not transfer more than two embryos
in a woman under the age of 35. The number of embryos transferred in women
over
the age of 35 is largely dependent on their prior IVF history and the
quality of the embryos themselves. Just about every pregnancy complication
imaginable
is increased when there is a multiple pregnancy. The most specific
baby-oriented risk of multiple pregnancy is premature delivery. Although
twins are somewhat
acceptable they are not desired. In higher order multiple pregnancies
than twins, a preferred option would be a process called selective reduction,
which is done at around 12 weeks’ gestation. This involves sacrificing
one of the fetuses to give the others a better chance at reaching maturity.

How painful is the egg retrieval process?
This is an invasive process and certainly involves some discomfort.
Prior to egg retrieval, I routinely give our VFC patients a session
of acupuncture, both to provide relaxation and also some form of
pain relief. After this acupuncture
session an intravenous line is established. In the operating room,
a combination of a sedative and narcotic is then administered intravenously.
After the
vagina has been cleaned, local anesthetic is injected into the vaginal
fornices before doing the retrieval. The retrieval is then done under
ultrasound guidance,
and extra narcotic and sedation given as necessary. Most patients find
that the procedure is not nearly as uncomfortable as they imagined.
If one has
to consider the discomforts caused by pregnancy itself, not to mention
the labour and delivery process, egg retrieval is normally minor
in comparison.
What side effects can I expect on the IVF medications?
The fertility drugs used do not seem to cause direct side effects,
and the side effects are therefore related to the actual effects
that these drugs have on the ovaries. As the ovaries begin to
swell, there can be some
pelvic and abdominal bloating. Some women do experience minor mood
changes, headaches and nausea – although all of these are uncommon.
Is there an increased risk of birth defects and
chromosome abnormalities in babies born after in vitro fertilization
and ICSI?
As a result of strict regulatory bodies, all babies born after
in vitro fertilization and ICSI are closely monitored. So far,
the worldwide results are very reassuring – although
it is appreciated that this is a young science. There do not appear to be any
increased risk of birth defects or genetic abnormalities in babies born after
standard in vitro fertilization. The process of ICSI is a micromanipulation technique
whereby a single sperm is injected into an egg. Because this overrides nature,
there is a chance that genetic material from a man who would otherwise be incapable
of impregnating a woman may be transferred to the offspring. It should be remembered
that in all naturally conceived children there is an approximately 4-6% of some
form of congenital abnormality occurring independent of maternal age. These abnormalities
would include things like clubfeet, cleft lip, hernias, extra digits, etc., etc.
It is possible that with ICSI there may be a slightly increased risk of congenital
birth defects – although there seem to be conflicting reports. For
the most part the data is very reassuring, and IVF/ICSI is felt to be a safe
science.

Is there an increased risk of cancer following infertility
treatments?
There has been some concern raised over the past ten years that
the use of fertility drugs and assisted reproductive technologies
may put
women at increased risk for either ovarian or breast cancer.
Adding fuel to this
concern was an irresponsible article published in the otherwise
usually reputable Oprah Magazine. There has been an official response to
this article from
our North American fertility association – The American Society
of Reproductive Medicine. I have included this response in a downloaded
PDF file which is available on this website. In summary, there
is
no conclusive evidence that there is an increased risk of either
breast or ovarian cancer
related to either fertility drugs or in vitro fertilization. When
digesting
all of this information, one has
to remember that first of all breast cancer is extremely common.
Approximately 12% of
all women will develop breast cancer in their lifetime. There are
so many different variables that it is sometimes difficult to ascertain
which may
or not may be a responsible cause. When it comes to ovarian cancer,
although the incidence is much lower (lifetime risk 1/60) there
is also some confusion.
Certainly, the most significant risk factors for ovarian cancer
are either family history or childlessness. In other words, women who
never
have a pregnancy
have an increased risk of ovarian cancer. It is therefore difficult
to establish whether or not the link with infertility is related
to not having children
or the use of fertility medications, which may have been used previously
in an attempt to assist conception.
These concerns continue to be monitored by our regulatory bodies, and
information will be passed on to all our patients as it becomes available.
At this time the reputable Cochrane Reviews do not find a link between either
breast or ovarian cancer and in vitro fertilization. However, it remains
our responsibility to use the most effective and efficient means to assist
patients in overcoming subfertility.

Does endometriosis affect fertility and can it affect
the success rates with in vitro fertilization?
Endometriosis is a condition in which the endometrial cells which normally
line the inside of the uterine cavity (womb) grow outside the uterus. Endometriosis
usually results in deposits (growths) of endometrial cells, which occur in
clusters, typically on the ovaries, fallopian tubes, bladder, pelvic side
walls and bowel. Endometriosis can also cause ovarian cysts (called chocolate
cysts). Less commonly, endometriosis can occur in other parts of the body
such as the lungs, liver and kidneys.
It is a confusing disease which may affect one in ten women during
their childbearing years. It is especially common, however, in women
having difficulty conceiving, and also in women experiencing pelvic
pain. The typical
symptoms of endometriosis include painful periods, premenstrual spotting,
painful intercourse and difficulty conceiving. Endometriosis should
be suspected in any woman with such symptoms. Although a clinical examination
and pelvic
ultrasound may be completely normal, some clues would include clinical
tenderness between the uterus and the rectum felt during an examination,
or ovarian cysts identified by
ultrasound. The condition can be confirmed by doing a surgical procedure
called a laparoscopy.
Laparoscopy involves a general anesthetic and passing a small telescope
through the belly-button (umbilicus) into the pelvic cavity to allow
direct visualization. For the most part patients with endometriosis
who require in vitro fertilization
have about the same chances for a successful pregnancy as patients
of the same age without endometriosis. However, there is some recent
research which
has identified an intrauterine chemical factor which may be associated
with endometriosis and decreased chances of pregnancy. For this reason,
depending on your personal history, we at VFC may suggest a different
type of IVF
protocol
to maximize your chances of conception during in vitro fertilization.
Furthermore, there may be a link between endometriosis and altered
immunity. The immune system in women is far more sophisticated than in men.
In women, the immune system needs to adjust to prevent rejection of the foetus,
which contains genetic material from the father. At the same time, it needs
to continue to do its job in protecting women from infections and other hostile
factors in our environment. It is for this reason that women are more prone
to immune-related disorders than men. Some of these include conditions like
rheumatoid arthritis, lupus and thyroid disease.
It has been long suspected that women with endometriosis may have a
mild immune imbalance, making them more vulnerable to this specific disorder.
If that is the case, it is also possible that such patients may be more likely
to have an IVF failure or miscarriage. This is currently being researched.

Is miscarriage more common after in vitro fertilization
than natural conception?
There does not seem to be a significant difference in the miscarriage rates conceived
naturally or through in vitro fertilization. The single most significant factor
related to miscarriage is maternal age. The risk increases with advancing age.
For a woman in the early twenties the miscarriage risk is approximately 12%,
however, for a woman in her early forties the miscarriage rate is between 25
and 50%. Another factor which affects significantly the risk of spontaneous miscarriage
is weight. For example, for women under the age of 35 and of normal weight,
the risk of
miscarriage is approximately 15%. For this same group of women who are in an
obese category (with a body mass index over 30) the risk of miscarriage is 35%.
What is the success rate with frozen/thawed embryos?
As with in vitro fertilization involving fresh embryos, the age of
the egg provider is the single most important predictor of outcome.
For embryos frozen on Day 3, approximately 70% will survive the freeze/thaw
process.
This may be higher for embryos frozen on Day 5 (blastocysts). The implantation
rate for a successfully thawed Day 3 embryo would then be dependent
on the maternal age of the egg donor. For women under 35, if two successfully
thawed
Day 3 embryos are transferred, the chances of pregnancy would be between
30 and 40%. These are therefore slightly lower pregnancy rates than
would be seen with a fresh cycle. The success rates will decline as age
advances.
What treatment options are available for women
over the age 40?
When the egg provider is over the age of 40 years, the chance of success
using her own eggs decreases significantly as we approach the age of 43/44.
Between the ages of 40 and 42, the chances for successful pregnancy per cycle
is around 30% if three embryos are available for transfer. By the age of
43 to 44, the chance of pregnancy falls to about 12-15%. There is also a
significantly increased risk of miscarriage, approaching 50% by the time
someone is 43 years old.
In vitro fertilization with egg donation is an option for all patients
when egg production or embryo quality appears to be a major factor. This
is especially relevant for patients over the age of 40 with decreased ovarian
reserve.
What is IVF using a donor egg?
For women without ovaries or for women with poor ovarian reserve (usually
related to age) an option for successful pregnancy would be in vitro
fertilization with donor egg. Preferably, such an egg donor should
be under the age of
35. During this process, the egg donor undergoes a cycle of in vitro
fertilization. Her ovaries are stimulated in the usual fashion as
described elsewhere in
this website, and then the eggs are retrieved by transvaginal ultrasound.
At the same time that this donor is going through an IVF cycle, the
recipient is undergoing a different process. This process involves
hormonal treatments
to prepare the uterus to receive the embryo.
After the eggs are retrieved from the donor, they are fertilized
using the recipient’s partner’s sperm (or donor sperm, depending on
the circumstances). The donor’s role is then over.
The embryos are then cultured, and then either on Day 3 or Day 5, transferred
into the uterus of the recipient.
Canadian Law does not allow the purchase of eggs. For this reason,
in Canada, the egg donor is expected to go through the process with
purely altruistic intentions. She is allowed, however, to be legally reimbursed
for expenses incurred during the process. There can be no financial
coercion during the process.
At VFC, we find that most of our egg donors are either relatives or
personal friends.
What effect to fibroids have on fertility and
the chances of success with in vitro fertilization?
Fibroids are the commonest tumour found in the human body. They are
round muscle growths which occur in the wall of the uterus. They are almost
always non-cancerous and harmless. They start as small pea-sized lumps but
grow steadily during the reproductive years. They may or may not cause symptoms.
Some of the common symptoms include heavy, painful periods and pressure on
the bladder and rectum. They can also uncommonly cause pain if they undergo
rapid change.
Fibroids that grow into the cavity of the uterus (submucous fibroids)
can definitely interfere with fertility. Such fibroids should be
removed prior to embarking on in vitro fertilization. Fibroids that grow
within
the wall of the uterus but do not displace or impact on the cavity
of the uterus
(the endometrial cavity) can potentially also interfere with the
chances of conception. This is a very controversial area. Generally speaking,
if fibroids are less than 5 centimetres in size and not impacting
on the
cavity
we do not recommend that they be surgically removed. We always
have to remember that a surgical procedure carries risk. The surgical
removal
of fibroids
is called a myomectomy. During a myomectomy there is a risk of
damage to the uterus – and as such the pros and cons of doing it
should be carefully evaluated.
On the other hand, as mentioned above, if fibroids are growing into
the cavity of the uterus they do need to be surgically removed. Most
of these can be tackled by doing a hysteroscopy. This involves passing
a fine telescope
through the vagina and cervix, resecting the fibroids and thereby
restoring the uterine cavity to normal.

Does stress affect the chances of success with
in vitro fertilization?
The frustration and sadness caused by infertility is up there
with cancer, loss of a loved one and major illness. Although fertility
treatments (including IVF) can be exciting and restore optimism,
they are extremely stressful. We encourage all of our patients
to meet with our reproductive psychologist to help deal with the
stress along the fertility journey. We have a holistic approach
to our medical care, and encourage our patients to learn coping
strategies, and to adopt lifestyle changes which are helpful to
their health in general. Specifically, we encourage exercise activities
such as yoga and complementary medical therapies like acupuncture/acupressure.
What is ovarian reserve?
Unlike men who continue to manufacture sperm until they die, women
are born with a finite number of eggs. At birth, the ovaries contain about
6 million eggs. By the time of puberty there are approximately 300,000 eggs
remaining in the ovaries for future ovulation. Although many eggs are recruited
each month during a natural cycle, usually only one egg matures. However,
it is a wasteful process, and many eggs are dying naturally every day.
In addition to the reduction in egg numbers as years advance, there
is also a decrease in egg quality. This is why the chances of conception
decline with advancing years. It is also the reason why there is an increased
risk for genetic abnormalities with advancing age.
There are two main ways of estimating ovarian reserve. The first is
to measure the level of follicle stimulating hormone (FSH) and estradiol
on the third day of the menstrual cycle. The second is to assess the volume
and
antral follicle count by ultrasound. The combination of these two tests
will give us an idea of the ovarian reserve and the chances for being able
to
recruit enough eggs to complete an in vitro fertilization cycle.

How do I contact the Victoria Fertility Centre?
You can contact our clinic through the contact e-mail address given
on the website. If you live locally, the preferred consultation should be
done in person. Appointments can be made through our front desk.
If you live out of town and would like to consider a treatment
cycle at Victoria Fertility Centre, Dr. Hudson would be happy
to do a telephone consultation at a pre-arranged time. Please
contact us with your details, and we can set this up.
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