In this type of stimulation, the Lupron (or other GnRH agonist) is started on cycle day 2 in the same menstrual cycle that eggs will be retrieved - instead of starting it a week prior to the start of menses. This protocol takes advantage of an initial "flare-up" response of FSH and LH release from the woman's own pituitary gland that usually occurs in the first 3 days of Lupron administration. Continuing Lupron for more than 3 days temporarily suppresses the pituitary gland so that it has very low output of FSH and LH.
The FSH product (e.g. Follistim, Gonal-F, Repronex) is then started on the following day (day 3). Lupron will stimulate release of a large amount of FSH (and LH) that will jump-start (flare-up) the follicles to promote a better ovarian stimulation, with more mature follicles and more eggs to utilize with IVF.
Birth control pills are usually given for the month before the flare so that there will not be a leftover cyst (corpus luteum) that could become reactivated by the high LH levels at the onset of the flare stimulation.
There are variations to the protocol. This is one example: