Cetrorelix acetate is a kind of gonadotropin releasing hormone (GnRH) antagonist. This product competes with endogenous GnRH for receptors on pituitary cells, thus inhibiting the release of endogenous (lewa) fschemicalbook, delaying the appearance of LH peak, and thus controlling ovulation. The effect of this product is dose-dependent, and the inhibition is direct, and maintained by continuous treatment, without causing the activity of luteinin receptor to rise at the initial stage and then down regulate.