Either gonadotropin-releasing hormone (GnRH) or any gonadotropin-releasing hormone agonist (such as Lupron) may be used in combination with luteinizing hormone (LH) using an infusion pump to simulate endogenous hormone production. GnRH stimulates the release of gonadotropins (LH and FSH) from the anterior pituitary in the body. This set of therapy is reserved for a subset of women with infertility and have produced ovulation rates of 90% and pregnancy rates of 80% or higher.[medical citation needed]