In-Vitro Fertilization (IVF), like natural fertilization and pregnancy, represents a combination of perfectly timed events. IVF treatment uses fertility medications to mimic the body’s natural hormones and to develop multiple eggs which will increase your chances for pregnancy.
Prior to beginning the administration of any fertility drug, a screening ultrasound scan will be performed to ascertain that there are no ovarian cysts which could interfere with proper ovulation induction. Most ovarian stimulation begin on cycle day 2 or 21 with daily subcutaneous injections of leuprolide acetate. When your estrogen level is adequately suppressed, FSH (Gonadotrophins) injections begin. The dose of fertility medication given is based on your weight and also your individual response during a previous ovulation cycle. Leuprolide acetate provides more control over the stimulated cycle by preventing a premature release of luteinizing hormone (LH) that may cause premature release of the eggs from the ovary. It also allows for synchronized follicle development producing more mature follicles of the same size. Gonadotrophins stimulate development of the fluid filled sacs on the ovary called follicles in which the eggs develop. The daily injections will continue until the follicles are a proper size and the blood estrogen levels reach an optimal level. hCG will then be used to mimic the body’s LH surge to bring about final maturation of the egg.
Careful ovulation monitoring of estrogen levels and follicle size optimizes ovarian stimulation and provides for increased safety. Blood estrogen levels are performed every 1-3 days from cycle day 2 until the administration of hCG.
Ultrasound scans are scheduled throughout the ovulation induction to monitor development of the follicles. It is not necessary to drink water to fill a bladder before the scans. We will ask you to empty your bladder prior to the ultrasound.
As ovulation induction progresses, the ovaries may become enlarged and tender. It is advised that strenuous activity be avoided after stimulation begins.
Ovulation induction of adequate follicle maturation is a difficult hurdle during IVF treatment. It is estimated that up to 25% of initiated cycles will be canceled prior to retrieval because of:
- Inadequate follicle development or hormonal levels
- Premature LH surges
Cancellation of a ovulation induction brings with it much disappointment, both for the couple and the fertility team. However, pregnancy rates depend on all factors being optimal. It is preferable therefore to begin a new induction in a later IVF cycle so eggs which are retrieved are the best quality possible.