Controlled Ovarian Hyperstimulation
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. IVF is performed in our Colorado location
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 for IVF. The particular protocol chosen for your cycle will depend on your history, age, weight, diagnosis, and your hormonal profile. Although most patients are seen at our Denver/ Parker location for IVF monitoring; IVF monitoring can occur in South Dakota, Wyoming, North Dakota with our outreach centers.
The exact IVF 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.
Rocky Mountain Fertility is a comprehensive Denver IVF clinic with in vitro fertilization consults provided at three fertility centers. Call for more information today!