ICSI is used when the male partners' sperm is suboptimal, when previous standard
IVF treatment has been associated with a low fertilisation rate and occasionally
used if only a few eggs are available. With ICSI a single motile sperm is isolated
from the male partner' sperm and the tail of the sperm is cut to immobilise the
sperm. The sperm is aspirated into a very fine glass needle (about one tenth of
the diameter of a human hair at its tip). The sperm is then injected directly into
the centre of the egg and the needle withdrawn. A very small percentage of eggs
can be damaged by the injection procedure but this is more than offset by the increased
fertilisation rate.
Are there any risks to the IVF/ICSI procedure?
Couples undergoing what is a relatively new procedure are naturally concerned to
know about all of the risks involved. Certain risks are common to in-vitro fertilisation
and ICSI; namely, the chance of developing ovarian hyperstimulation syndrome and
the chance of multiple pregnancy. However, while there have been nearly two million
babies born following standard in-vitro fertilisation treatment, the number of babies
born following ICSI is probably a few hundred thousand. From assessment of these
babies following ICSI, the following represents the current state of our knowledge
about the possibility of abnormalities. It is an unfortunate fact that 3 in every
100 babies born naturally, i.e. not as a result of fertility treatment, are born
with a major malformation. The largest studies performed to date of 3,000 pregnancies
following ICSI treatment has shown that the overall percentage of ICSI babies born
with an abnormality is no greater than that arising in the normal population.
Over the past few years it has been realised that approximately 10% to 15% of men
who have no sperm or very low numbers of sperm have a specific defect in one of
their genes that is responsible for producing sperm (this is called the DAZ gene).
It is quite possible that this gene defect will be passed on to a male child, which
could result in the child also, in the future, being infertile.
- Ovarian Hyperstimulation Syndrome
This is probably the most serious side effect of in-vitro fertilisation treatment.
It is related to the drug stimulation that you receive rather than the in-vitro
fertilisation itself and the syndrome can occur in women receiving these drugs for
other reasons. As the ovaries are stimulated more than would normally be the case
in a natural cycle, they always are larger than normal and contain fluid filled
structures (follicles), which contain the eggs. This occurs in all women having
IVF treatment and is not a cause for concern. In approximately one woman in a hundred,
the more serious form of ovarian hyperstimulation syndrome develops. Here, the ovaries
become greatly enlarged and contain large cysts. These cysts produce copious quantities
of fluid, which is released into the tummy cavity. The fluid is rich in minerals
and protein. The symptoms of severe ovarian hyperstimulation syndrome include abdominal
pain, a marked degree of abdominal swelling, shortness of breath, nausea and possibly
vomiting, and a reduction in urine output. In the presence of severe symptoms, hospitalisation
may be necessary. This enables the fluid minerals and protein to be replaced and
corrective measures put in place to prevent further complications. Due to the seriousness
of the problem, prevention is better than cure. Although it is not possible to be
certain about which patients will develop ovarian hyperstimulation syndrome, those
with the ovarian hormone abnormality called polycystic ovaries are known to be more
at risk. This will be assessed at the time of your preliminary consultation prior
to starting IVF treatment. Patients who respond to the drug treatment by producing
very many eggs, particularly if they are experiencing lower abdominal pain before
the time of the egg collection are also at increased risk. In these circumstances,
the treatment cycle may be cancelled before the late night pregnyl injection or,
if the egg collection is performed, all of the embryos may be frozen and none transferred
immediately. This should reduce the chance of the serious form of hyperstimulation
syndrome from developing.
- Multiple Pregnancy
The Ministry of Health Singapore has recently advised all IVF clinics that no more
than 3 embryos can be transferred in an IVF cycle except in exceptional cases eg:
patients over the age of 40 years having treatment with their own eggs. Many infertile
couples are quite pleased at the idea of having twins although most couples would
prefer not to conceive a triplet pregnancy. It is still possible to conceive a triplet
pregnancy even if just 2 embryos are replaced and this happens if one of the embryos
divides into identical twins. Fortunately this is very uncommon. In couples who
conceive naturally, the chance of a twin pregnancy is approximately one in every
eighty pregnancies. With IVF treatment, the chance of a twin pregnancy is one in
every three to four pregnancies. Apart from the social and professional problems
of multiple pregnancies, particularly triplets, the medical problems related to
the carriage of two or three babies can be very significant. These include an increased
risk to the mother of pregnancy related complications such as high blood pressure,
diabetes and haemorrhage. Problems for the babies include the risk of delivery of
very premature babies who may not survive or who may survive with important handicaps
including brain damage. The ideal outcome of IVF is to have a single healthy baby.
- Infection/Haemorrhage
At egg collection a fine needle is passed through the vagina into the ovary to remove
the eggs. There is a small risk at that time of causing bleeding from the ovary
or introducing inflection into your pelvis. Great care is taken during the egg collection
to minimise these risks and antibiotics are given. In practice, while a little bit
of spotting of blood from the vagina is likely after the egg collection, significant
bleeding is extremely rare. The chance of infection is less than one in one hundred.
On average, approximately ten eggs are collected per patient resulting in an average
of seven embryos per patient. Usually no more than two embryos are transferred at
a time. It is possible to freeze some of those embryos, which are not immediately
transferred. The decision to freeze the embryos will depend on the number and quality
of embryos remaining. It is known that embryos that are not of good quality (as
shown by their physical appearance under the microscope) will be unlikely to survive
the freezing and thawing procedure. However, if there are a sufficient number of
good quality embryos available, these can be frozen and preserved in this state
for up to ten years. Under the Singapore Ministry of Health Guidelines for embryo
freezing, the current policy is for the embryos to be frozen for up to 5 years in
the first instance. This period can then be extended to 10 years in certain special
circumstances. The frozen embryos can be thawed out and transferred back into your
uterus in a subsequent cycle or cycles. The chances of pregnancy resulting from
frozen embryos are not as good as that from fresh embryos but, nevertheless, this
does offer a supplementary chance compared to if freezing was not available.
|