Controlled Ovarian Hyperstimulation or COH, is a medical treatment sometimes utilized to improve the chances for pregnancy. COH may be used prior to intrauterine insemination or in vitro fertilization and is offered to some couples who have:
- Unexplained infertility (after a complete evaluation)
- Cervical factor infertility
- Male factor infertility
- Mild endometriosis
- Persistent infertility despite other treatment
The technique involves the controlled stimulation of the ovaries by medication to increase the available number of eggs that can be fertilized per cycle. Additionally, the technique allows for precise timing of insemination with the husband’s sperm placed directly into the uterus through the cervix.
COH is comprised of two steps:
1. Induction of multiple ovulations (follicles or eggs)
2. Sperm preparation and insemination
back to top
Induction of Multiple Ovulations
In order to increase the effectiveness of COH, medication is used to induce (bring on) ovulation of multiple eggs. Primarily, Follicle Stimulating Hormones (FSH) or Human Menopausal Gonadotropins (hMG) are used to induce multiple egg development and maturity. The medications are given in a set sequence as determined by your physician.
Typically, the medications are given subcutaneously or intramuscularly beginning on the third day of the cycle and are continued until it is time to induce ovulation. Human Chorionic Gonadotropin (hCG) will be given by either subcutaneous or intramuscular injection at the time selected by your physician to complete the maturation of the eggs and induce ovulatory response. These medications have been used extensively and are usually safe and effective when administered with careful supervision. No increase in either congenital abnormalities or birth defects has been associated with these medications. In addition, you may receive a GnRH antagonist given daily by injection or twice daily by nasal spray to enhance the ovarian response.
The desired response is to obtain two to four eggs capable of ovulation per cycle. If more than four eggs develop, the cycle may be cancelled due to the risk of multiple pregnancy and / or ovarian hyperstimulation syndrome (see side effects).
During the time you are taking medications to induce ovulation, your response will be carefully monitored to ensure your safety and improve success with COH. In addition to physical examinations, two other monitoring systems with be utilized:
Hormonal Monitoring: Blood samples will be drawn for assessment of the hormonal response of the ovaries during ovulation induction. Blood will be drawn between 8 a.m. and 9 a.m. for estradiol (E2) levels at intervals determined by your physician.
Ultrasound Monitoring: Ultrasound is a simple and safe technique, which allows assessment of the ovarian response to stimulation, namely the size and number of ovarian follicles. Ultrasound will be performed with a vaginal probe. The probe will be placed within the vagina once the bladder is emptied. The procedure takes 5 to 10 minutes to perform. Ultrasound monitoring will be performed prior to the start of the medications and at intervals thereafter as determined by your physician.
back to top
Sperm Preparation and Insemination
It will be necessary to obtain a semen specimen on the day of insemination. The specimen must be collected in a sterile manner in a container supplied for the male partner. Abstinence for 48 hours is required prior to the specimen collection. Approximately one hour prior to the insemination, the semen specimen must be at the lab. The specimen should be kept near body temperature (98.6 F) and be taken to the lab within about one hour of collection.
In the laboratory, the semen sample will be specially prepared using the technique of sperm wash and “swim up.” These procedures allow the laboratory personnel to collect the most motile (active) sperm.
The sperm sample will be inseminated into the woman’s uterus (intrauterine) by placing a small catheter through the cervix into the uterus. While some patients experience mild cramping, the procedure is usually painless and requires only 1 to 2 minutes to perform. The woman is then asked to rest quietly for 10 minutes before she leaves the exam room.
back to top
Reasons for Cancellation of a Treatment Cycle
There are several possible reasons for canceling a COH/IUI treatment cycle, including:
- Inadequate follicular development or hormonal response
- Excessive number of available follicles or inappropriate maturation
- Inability to obtain a semen specimen on the day of insemination
- Complications of ovulation stimulation
back to top
