Stimulation Phase

During this very important phase of the IVF cycle, patients receive daily (occasionally twice daily) injections of gonadotropins – hormones, which stimulate the ovaries to produce multiple eggs. The common names for these gonadotropins are Follistim and Repronex. The “stim” phase of the cycle lasts on average 10 days, but can vary from 8 to 12 days, are necessary. At each visit blood will be drawn to study the change in the hormones and a vaginal ultrasound will be performed to note the progression of the ovarian follicles.

The staff will make frequent reference about follicles – their number and size. Within each follicle is an egg. The egg is very small and cannot be seen on ultrasound. The fluid filled follicle surrounding the egg, however, is much larger and because fluid stands out on ultrasound, it is very easy for us to locate, count and measure the size of each follicle. Most importantly, the size of the follicle correlates with the maturity of the egg! The larger the follicle, the nearer the egg to being ripe and ready for harvest (a procedure we refer to as follicle aspiration, or retrieval). The egg within a follicle is usually mature – and ready for harvest- when the follicle measures between 16 and 20 millimeters.

Just before stimulation begins the follicles are usually small and often not visible and Estradiol (estrogen) levels are low. Large follicles (greater than 12mm) or elevated Estradiol levels at the start of stimulation usually indicates that a woman is not truly at day 3, and often necessitates postponing the cycle. A suppression check (a blood test and an ultrasound) is done in the days prior to the start of stimulation to ensure that all is ready. As stimulation progresses through the early stages (the first 5 days) the follicles usually show only minimal growth, but estrogen levels (measured as Estradiol) start to increase.

Soon thereafter, the follicles start to grow and once they reach about 12 to 14mm, they will grow fairly predictably at a rate of 2mm per day. During this phase of growth you will be monitored closely, sometimes as often as daily. The Doctor reviews lab results and follicle sizes after each visit. The nurse also calls all of their patients later in the day to update them on any medication changes that need to be made. Frequently, the combined results of the ultrasound and the lab work will necessitate either slowing the cycle down (decreasing the dose of medication) or speeding it up (increasing the medication).

One of the problems in the early days of IVF was that dramatic rise in Estradiol would cause the eggs to “ovulate”, that is, to be released from the ovary. Once released, the egg can no longer be retrieved, and entire cycles were ruined. When Lupron became available, daily injections of this medication were found to suppress the tendency toward premature ovulation, thus allowing longer cycles and better quality eggs. For years, Lupron has been an essential part of the stimulation phase of IVF.

Ovarian Stimulation After about 2 weeks of pre-treatment with the GnRH agonist, we add daily injections of FSH & LH (known as Pergonal, Puregon or Gonal F). The injections continue for about 12-14 days. The amount of FSH & LH used is somewhat higher than you would produce on your own. This is what stimulates the growth of several follicles, instead of just one. The response of the ovaries is monitored with frequent blood tests and ultrasounds. These are done between 8:00 and 9:00 each morning. Most women learn to give their own injections in order to reduce the number of clinic visits. You will be taking fertility shots for about ten days to stimulate multiple eggs to develop. You will continue to take Lupron all this time and you can expect several ultrasounds and blood tests to monitor the development of the eggs. Women can respond differently to the fertility drug injections and may need adjustment in the amount of medications taken.

Follistim AQ Cartridge acts like naturally produced follicle-stimulating hormone (FSH), the hormone that stimulates the ovaries. It binds to the surface of the immature follicle to trigger a series of events that lead to the growth of the follicle and the maturation of the egg. Follistim® AQ Cartridge (or other drugs containing FSH) will not induce ovulation. For ovulation to occur, a second hormone called Pregnyl® (chorionic gonadotropin for injection, USP) is administered. Pregnyl® acts like luteinizing hormone (LH) to induce ovulation and release the mature egg from the follicle.

Follistim AQ Cartridge is administered as a subcutaneous injection (under the skin) using the Follistim Pen. You load a pre-mixed, pre-filled Follistim AQ Cartridge containing the medication into the Follistim Pen, dial up your exact dose and give yourself an injection.

Follistim AQ Cartridge is usually administered once daily. The recommended daily dose is 75 IU or lower for patients undergoing ovulation induction, with a maximum daily dose of 175 IU. A 150 to 225 IU starting dose, with a maximum daily dose of 450 IU, is recommended for the first 5 days of treatment for patients undergoing controlled ovarian hyperstimulation for IVF.

Before beginning therapy, your doctor will explain the standard tests and monitoring procedures that he or she will use to track your progress. It is very important that you keep all your appointments during therapy since infertility treatments require precise timing of hormone injections and induction of ovulation. Delays may lead to cancellation of the treatment cycle or complications.