What happens if I ovulate before the egg collection?
One of the concerns with ovarian stimulation is what happens if a woman ovulates prematurely before the egg collection, which means that the eggs cannot be retrieved. One of two classes of medications are typically given to prevent this from happening. The first class of medicines are call GnRH agonist. The agent most typically used in the United States is leuprolide acetate (Lupron and generics).
Lupron causes the pituitary gland to release high amounts of FSH and LH (luteinizing hormone) for several days until its stores are depleted. Since continued use of Lupron prevents the pituitary gland from producing new supplies of FSH and LH, the amount of these hormones being released per day becomes very low after 7 to 10 days.
The goal of Lupron is to ensure that blood levels of LH are low during the last few days of follicle growth. High levels of LH can lead to poor egg quality, ovulation before egg collection, and stimulate progesterone production by the ovaries. A premature rise in progesterone may cause inappropriate maturation of the uterine lining and lead to lower chances of embryo implantation. Some women will be placed on a Lupron “flare” medication schedule. This involves starting Lupron early in the menstrual cycle after suppressing pituitary and ovarian function for up to one month of birth control pills.
The Lupron causes a rapid increase in FSH and LH release by the pituitary gland and initiates follicular growth but over time also suppresses ovulation. On the third day after the Lupron starts, the woman begins shots of gonadotropins to stimulate the continued growth of the follicles as the pituitary’s release of FSH begins to decline.