Follistim® AQ Cartridge contains follitropin beta, which 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.
Although follitropin beta in the Follistim® AQ Cartridge causes the follicles to mature, it does 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). It induces ovulation and releases the mature egg from the follicle.
You can read more about Follistim AQ Cartridges here.