Overview for In Vitro Fertilization Patients
Introduction
In vitro fertilization is a procedure that enhances the chance of pregnancy in couples
for whom other fertility therapies have been unsuccessful or are not
possible. It involves many steps resulting in the insemination and
fertilization of eggs in a laboratory. The embryos created in this
process are placed into the uterus for implantation. In vitro fertilization is elective
medical treatment that may help an infertile couple have a child of
their own. This is an explanation of the in vitro fertilization process.
Stimulation and Monitoring
Superovulation techniques are used in in vitro fertilization to stimulate the ovaries
to produce several eggs (oocytes) rather than the usual single egg
as in a natural cycle. Multiple eggs increase the chance of obtaining
many embryos (fertilized eggs) for transfer and the probability of
conception. There are many medications required to boost egg production.
Each is administered by injection only. Some are given subcutaneously
(beneath the skin), and the others are given intramuscularly (into
the muscle).
These ovulation induction medications cause the ovaries to produce
more than one egg to grow. Hormone levels of estrogen and progesterone
reach levels much higher than normal. When the estrogen level becomes
elevated, side effects may be experienced. These possible side effects
make it important for us to carefully monitor your response to these
medications. This monitoring also allows your physician to determine
when the eggs are ready for the next stage, oocyte (egg) retrieval.
Monitoring includes frequent blood drawing for hormone levels. These
blood tests will take place over approximately a twelve-day period.
Another part of monitoring in vitro fertilization involves the use of intravaginal
ultrasound to track follicular growth. The eggs develop inside fluid-filled
sacs in the ovaries called follicles, which enlarge as the eggs mature.
Ultrasound studies are performed on a frequent basis until oocyte
(egg) retrieval once your medications begin.
Egg retrieval
For in vitro fertilization, collection of eggs is usually performed with transvaginal
ultrasound guidance. Under in vitro fertilization sedation patients are given pain medications
intravenously and are carefully monitored by a nurse anesthetist.
Retrieval is accomplished by insertion of a needle through the vaginal
wall into the ovaries using ultrasound to locate each follicle. The
follicular fluid is drawn up into a test tube to obtain the eggs.
Generally, the oocyte (egg) retrieval takes 30-45 minutes. Patients
are usually discharged home within an hour after the retrieval.
Collecting and Preparing the Sperm
A semen sample will be obtained from the partner by masturbation
on the day of the oocyte (egg) retrieval. This is usually obtained
while the retrieval is being performed. Abstinence from ejaculation
for two to three days prior to providing this semen specimen is recommended.
After the specimen is produced, the sperm will be prepared for inseminating
the collected eggs in our laboratory. A second sample of fresh semen
is occasionally needed the day of retrieval to inseminate egg(s).
Men who feel that they may have difficulty producing a semen specimen
have the opportunity to have their specimens frozen by our laboratory
ahead of time for use in this situation.
Insemination of Eggs and Embryo Culture
Following egg retrieval, the follicular fluid is immediately transferred
to the nearby laboratory for identification of eggs, evaluation, and
preparation for insemination. The prepared sperm will be added to
each egg or injected directly into it if there is a sperm problem
(intracytoplasmic sperm injection) and they will be allowed to incubate overnight under controlled
laboratory conditions. The next day, each egg is checked for evidence
of fertilization. However, it is possible that no eggs are fertilized.
If fertilization does not occur, the remainder of the procedure will
be cancelled. The eggs that have fertilized will be allowed to develop
for one or more additional days under controlled laboratory conditions
before they are placed inside the woman's uterus (womb). Depending
upon the couple's wishes, some fertilized eggs or embryos may be frozen
and stored for future use. After the embryos are transferred to the
uterus, the woman will take progesterone supplementation that begins
on the day after the egg retrieval procedure. Progesterone is usually
taken by injection. Administration of this medication after egg collection
has been shown to create a more favorable uterine environment for
the embryos, which increases pregnancy rates.
Transferring Embryos to the Uterus
Embryos are transferred to the uterus through a small tube (catheter).
This procedure is much like a pap smear and does not require any anesthesia.
The embryos are placed in a small amount of fluid inside the catheter,
which is passed through the cervix at the time of a speculum examination.
The number of embryos transferred depends on individual circumstances
of the couple and the day of transfer. This decision will be made
collectively by you, your physicians and the embryologist. Many factors
will be taken into account. The transfer of several embryos increases
the probability of success. A multiple embryo transfer also increases
the risk of a multiple pregnancy. The multiple pregnancy rate with
in vitro fertilization is about 28%. Most of these will be twins, but depending on the
number of embryos transferred triplets or higher order multiples can
occur. A procedure called “selective reduction” is available after
counseling in these cases. We will give you written information and
discuss this with you at your consult appointment.
Embryo transfer can cause mild cramping. After transfer, the woman
may get dressed and leave after a brief recovery period. A pregnancy
test will be done twelve to fourteen days after the transfer, even
if she has bleeding or spotting.
Couples going through therapy must choose and formalize their choice
for handling of any remaining embryos by indicating one of the following
options:
- Freezing (cryopreservation) of remaining embryos for use by the
couple in future treatment cycles
- Anonymously donating the embryos for use by another infertile
couple(s), if the donating couple and the donated embryos meet the
screening criteria (You would not receive any money for this donation,
nor would they be sold.)
- Allowing the embryos to develop in the laboratory until they perish,
at which time they would be disposed of in a manner consistent with
professional ethical standards and applicable legal requirements.
Other Issues:
Any assisted reproduction process or technique can be psychologically
stressful. Significant anxiety and disappointment may occur. We encourage
you to consider short-term supportive counseling during this time
and we are happy to provide you with the name of counselors before
you cycle to review your feelings and help you through what may be
a difficult time emotionally for you and your partner.
A substantial time commitment is required by both partners to complete
an entire course of in vitro fertilization. It will be necessary for couples to adjust
their schedules to undergo the required testing and therapies associated
with in vitro fertilization-ET. It is your responsibility to be available for scheduled
ultrasound examinations and blood tests over the time period involved
in the in vitro fertilization process. It is the responsibility of the man to be available
the day of retrieval and embryo transfer.
Reasons for Unsuccessful Cycle:
Unfortunately, neither conception nor a successful outcome of pregnancy
is guaranteed by the in vitro fertilization-ET procedure. There are many reasons why
pregnancy may not occur with the in vitro fertilization-ET procedure. In fact, there
are complex and largely unknown factors that limit pregnancy rates
following assisted reproductive techniques. Some of the known reasons
for failure include:
- There may be a failure to recover an egg because:
- follicles that contain mature eggs may not develop
- ovulation has occurred before time of egg recovery
- one or more eggs cannot be recovered from the follicles seen
- pre-existing pelvic scarring and/or technical difficulties prevent
safe egg recovery
- The eggs that are recovered may not be normal
- There may not be enough semen to attempt fertilization of the
recovered eggs because the man is unable to produce a semen specimen,
because the specimen does not contain enough sperm for fertilization,
or because the option to use a donor sperm as a "backup"
was declined;
- Fertilization of the eggs to form embryos may fail even when the
egg(s) and sperm appear normal;
- Embryos may not develop normally or may not develop at all. Embryos
that do not appear to develop normally will not be transferred;
- Embryo transfer into the uterus may be difficult/impossible, or
implantation(s) may not occur, or the embryo(s) may not implant
or develop normally after they are implanted in the uterus
- Any step in the in vitro fertilization-ET process may be complicated by unforeseen
events, such as hazardous or catastrophic weather, equipment failure,
laboratory conditions, infection, human error and other unforeseen
events.
When pregnancy occurs following in vitro fertilization, it will typically be a normal
pregnancy. However, there is always a risk of abnormal pregnancy such
as, miscarriage, blighted ovum, ectopic pregnancy or premature delivery.
This is because the process of in vitro fertilization-ET does not protect against such
occurrences. Congenital abnormalities, genetic abnormalities, mental
retardation or other birth defects which occur in approximately 3-4%
of spontaneously conceived pregnancies may still occur in children
born following assisted reproductive techniques. Women with multiple
pregnancies have a much higher risk of complicated pregnancies, which
may include the following: toxemia (pre-eclampsia), miscarriage, premature
labor and delivery, stillbirth, birth defects, and other complications.
Ovarian stimulation with the fertility medications causes multiple
follicles to develop. Approximately 25-28% of pregnancies with in vitro fertilization
will be multiple. Most of these will be twins, but triplets, quadruplets
or even greater multiple pregnancies can occur, but are rare. A procedure
called "selective reduction of pregnancy" can be performed
and may be considered after counseling.
Alternatives to In Vitro Fertilization-ET:
Depending upon the individual and unique cause(s) of infertility
for each couple, the chance of conception through alternative means,
including intrauterine insemination (IUI) and medicinal therapy, other
than in vitro fertilization-ET may or may not exist. Possible success rates of these
alternatives may vary depending upon the type and severity of the
cause of the infertility. For some couples, it may even be possible
to conceive spontaneously without a physician's help. You should discuss
these alternative treatment methods with your physician before you
proceed to treatment.
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