Treatment of Endometriosis With Norethindrone Acetate ( NA) VS. Gonadotropin- Releasing Hormone (GnRH) Agonist (Lupron Depot 11.25 mg)

(A) Major 1) to compare the effectiveness of norethindrone acetate (NA) with GnRH agonist (Lupron-Depot-3) in relieving symptoms of endometriosis, 2) to compare bone density in the two treated groups in order to demonstrate that NA does not affect bone density; (B) Minor: 1) To compare the lipid profiles of patients in the two groups to confirm the hypothesis that the effects of NA and GnRH agonists on lipid profiles are similar, 2) To determine whether quality of life, assessed by questionnaire, is better in patients assigned to NA than in patients assigned to GnRH, 3) To determine whether NA has fewer adverse effects than GnRH agonist.