In Vitro Fertilization - Stage 1
Controlled Ovarian Hyperstimulation
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During a normal menstrual cycle, while a group of oocytes (eggs)
begin development only one progresses to maturity. In an effort to
increase the chances for a pregnancy with IVF, it is necessary to
stimulate multiple oocytes to develop. This increases the number of
oocytes available for fertilization and transfer.
The follicle is a small fluid-filled structure located in
the ovary which contains the oocyte (egg). The amount of fluid in
the follicle increases as the egg matures, thereby increasing the
size of the follicle. This growth can easily be observed and
measured by ultrasound. The number of follicles, their sizes, and
normal growth guides the decision as to when oocyte maturity has
occurred and retrieval should take place. Estradiol is the primary
hormone produced by a healthy egg. The measurement of this hormone
in the blood also helps to guide our decision as to the maturity of
the eggs and the timing of the retrieval. Several stimulation
protocols are available. The particular protocol chosen for your
cycle will depend on your history, age, weight, diagnosis, and your
hormonal profile.
Stimulation Regimes
The exact protocol selected will be determined by your history
and any prior reproductive procedures you may have had. If one of
these protocols is most appropriate for you, this will be discussed
individually.
Luteal Phase Lupron: Suppression with Lupron after taking
OCP’s for 3-6 weeks. Stimulation with hMG occurs 10-14 days after
Lupron start.
Sequential Clomiphene Citrate (CC)–FSH: Oral contraceptive
pills (OCP’s) must be utilized prior to this stimulation. This
allows a resting state of the ovary before the stimulation begins.
CC will be utilized along with the human menopausal gonadotropins.
Long-Lupron Suppression: For patients with polycystic
ovarian syndrome or endometriosis, a three-month course of Lupron
may be advised prior to starting stimulation. This allows adequate
time to suppress the ovary that may lead to poor oocyte development,
fertilization, and poor embryo quality. Once the three months of
suppression has occurred, the stimulation is very similar to that
described above for “standard IVF”.
Higher-Dose hMG: Lupron will be utilized for suppression
of endogenous FSH and during the stimulation (i.e. 10 units for
suppression and 5 units for the stimulation portion of the cycle).
The dosage of hMG will be increased.
Demi-Halt: Lupron, at half the full dosage (10 units), is
started in the cycle prior to stimulation. With the onset of the
stimulatory medication the Lupron is stopped.
Microdose Flare: Oral contraceptive pills (OCP’s) must be
utilized the cycle prior to this stimulation. This allows a resting
state of the ovary before the start of stimulation. A very low dose
of Lupron (1/10 the regular dose) is then begun on the fourth day
after stopping OCP’s. Two days later FSH is begun at a dosage of 4-5
ampules daily. This dosage of FSH and the low-dose Lupron will
continue until hCG is given.
GnRH Antagonist: Oral contraceptive pills are utilized in
the cycle prior to stimulation. No Lupron is utilized. The GnRH
antagonist is added around cycle day 6-10.
Other new stimulations may be utilized, as needs and science
dictate, and will be discussed individually with couples prior to
the active cycle.
The process of stimulating an increased number of oocytes is
called "controlled ovarian hyperstimulation (COH)". The
stimulation is accomplished through the administration of hormonal
drugs. Careful monitoring is required on a daily basis to make sure
the induction is proceeding appropriately. Monitoring is
accomplished through closely following the blood level of estrogen (estradiol)
and through observing the growth of the follicles by ultrasound.
Most cycles will involve pretreatment with a GnRH agonist or GnRH
antagonist which blocks the body’s release of FSH and LH to allow
better control of the cycle.

Cancelled Cycles: While we try to stimulate the ovaries to
produce a number of mature eggs, sometimes the result may be less
than expected. Under these circumstances, when the chance of
successful pregnancy is not acceptable, it is best to abandon
treatment. Another trial can be arranged using the new knowledge of
the poor response to dictate an alternative stimulation protocol
There is no reason to panic or to put blame on yourself. It is
also not advisable to compare your own response with others. Every
woman has her own biological variation. During the treatment cycle,
you are going through a very stressful period. A cancelled cycle can
add even more stress. Let our staff and doctors assist you.
Risks: The drugs utilized for controlled ovarian
hyperstimulation are very powerful. The goal is to override the
body’s protective mechanism which tries to ovulate only one egg.
While our goal is to increase the number of eggs available, there is
a risk of over stimulation. All women will experience mild symptoms,
during and after ovarian stimulation, of abdominal bloating and mild
discomfort. A severe form of “ovarian hyperstimulation”
occurs in less than 1% of women and may require hospitalization for
management. Serious complications such as blood clot or damage to
the kidney rarely occur.
If you are at increased risk of hyperstimulation (based on
estradiol levels or number of follicles), several options are
available: 1) cancellation of the cycle, 2) continuing with cycle
after cessation of drug (“coasting”), 3) retrieval with freezing of
all embryos (pregnancy increases hyperstimulation risk fourfold), or
4) continuing with a decreased hCG dosage and additional treatment
during the retrieval.
There have been conflicting medical research studies linking the
use of ovulation inducing drugs with the risk of developing ovarian
cancer. Therefore, a definite statement about the risk of ovarian
cancer is impossible to make at this time. There also may be
presently unknown or unclear risks, such as impaired future
fertility, associated with these treatments.
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