title: Improved long-acting fertility regulating agents: what are the problems?
mesh_terms: D000523:Algestone / Q000097:blood; D003271:Contraceptive Agents, Female / Q000009:adverse effects; D003692:Delayed-Action Preparations; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D008525:Medroxyprogesterone; D009640:Norethindrone / Q000097:blood; D010053:Ovary / Q000502:physiology; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D013256:Steroids / Q000009:adverse effects; D013329:Structure-Activity Relationship
chemical_list: D003271:Contraceptive Agents, Female; D003692:Delayed-Action Preparations; D013256:Steroids; D000523:Algestone; D011374:Progesterone; D004958:Estradiol; D008525:Medroxyprogesterone; D009640:Norethindrone