During the initial stages of the IVF process, reproductive endocrinologists prescribe Ganirelix to inhibit the release the luteinizing hormones GnRH-antagonist action, resulting in the suppression of LH and FSH production until the follicles are mature. Doctors can then take control of the woman’s reproductive system in an attempt to delay ovulation. This is so she won’t release an egg at the wrong time in the course of her natural menstruation cycle.

Another drug that may also be prescribed to perform the same job is Lupron. The difference is Ganirelix works by competing with native GnRH molecules at their binding sites in the pituitary gland, while Lupron works by “down regulating” the pituitary’s ability to produce the LH surge. The bottom line is that both drugs, antagonist and agonists, prevent LH surges, but in different ways.

The use of Ganirelix results in less total number of shots being taken over the course of the stimulation cycle than by using Lupron. There is, however, some evidence that Ganirelix results in slightly fewer eggs retrieved (on average), slightly less embryos available on the day of transfer (on average), and slightly lower pregnancy rates than with the use of Lupron. Pregnancy rates, however, are still excellent with Ganirelix when used in selected patients, and some clinics report that women who are low responders to ovarian stimulation protocols that involve the use of Lupron might be able to stimulate better if an antagonist such as Ganirelix is used instead.

How to Use Ganirelix

Before using Ganirelix, your health care professional will train you on how to use the medication properly. Typically, Ganirelix is self-injected (or a partner can do it for you) subcutaneously just under the skin—usually in the abdominal area. Shots should be administered once daily, and continued for 7-12 days until enough follicles are mature. It is strongly advised that the patient injects the prescribed dose that is directed by the doctor. Ganirelix and FSA injections are continued until the time of the hCG injection, in which you will be closely monitored by your doctor, who will determine the right time to discontinue the drug.

Staying on Ganirelix for a relatively long amount of time can induce the feeling of going through menopause (hot flashes, vaginal dryness, etc.). Most of the time, however, a fertility doctor will use it at a time in your cycle when estrogen levels are high, which will cut back on these symptoms.

References

Drugs & Medications – ganirelix subq. (2005-2014). Retrieved from www.webmd.com: http://www.webmd.com/drugs/drug-75166-ganirelix%20subq.aspx

Drugs and Supplements-Ganirelix. (2014, August 1). Retrieved from www.mayoclinic.org: http://www.mayoclinic.org/drugs-supplements/ganirelix-subcutaneous-route/description/drg-20064001

IVF Medication Protocols for Ovarian Stimulation with Antagonists. (1996-2014). Retrieved from www.advancedfertility.com: http://www.advancedfertility.com/ivf-stimulation-antagonist.htm