Controlled Ovarian Stimulation (Superovulation)

In a normal menstrual cycle, the ovaries typically produce a single mature egg. In order to maximize pregnancy opportunities, medications are administered to stimulate the ovaries to produce many eggs in an IVF cycle. These medications are called follicle stimulation hormone (FSH) and are administered by subcutaneous (SC) injection. These medications are required for 9-14 days (on average 12) and are self administered by the patient. The follicular development is monitored by serial transvaginal ultrasound examinations and estradiol (E₂) levels. Once the monitoring results indicate mature eggs (appropriate follicle size and estrogen levels), another hormone called Human Chorionic Gonadotrophin (hCG) is given to complete the final maturation process and the egg retrieval is scheduled for 35 hours later. These medications rescue eggs that would otherwise be discarded naturally in a normal menstrual cycle.

A typical IVF cycle will require an ultrasound examination and estradiol levels prior to starting superovulation (suppression check). Repeat testing of estradiol and ultrasound will be arranged on Day 4, Day 7 and about every second day after day 7 while on the FSH medication. The monitoring process is individualized and patients that are at high risk for ovarian hyperstimulation syndrome (OHSS) may require daily monitoring.

All monitoring with estradiol blood tests and ultrasounds are done at the Regional Fertility Program during treatment. The IVF team including physicians, nursing staff and the embryology staff meet daily and discuss patients' results in order to ensure the best decisions are made with regard to medication dosage, timing of hCG and number of embryos to transfer.

Side Effects

The active medication used to stimulate the ovaries is follicle stimulating hormone (FSH). These medications are commonly known as Gonal F®, Puregon® and Menopur®. These medications act directly upon the ovary to stimulate multiple follicular development. Common side effects include bloating, enlarged ovaries, nausea, diarrhea, and tender breasts. Serious side effects can occur as a result of ovarian hyperstimulation syndrome (OHSS). This may cause ovarian enlargement, fluid in the abdomen (ascites), difficulty breathing, kidney failure and blood clots which in rare and extreme circumstances can even result in death.