title: [Double blind study with an oral contraceptive (preliminary report)].
mesh_terms: D002986:Clinical Trials as Topic; D003276:Contraceptives, Oral; D005260:Female; D006801:Humans; D007434:Intrauterine Devices; D008656:Mestranol; D009640:Norethindrone; D010919:Placebos
chemical_list: D003276:Contraceptives, Oral; D010919:Placebos; D008656:Mestranol; D009640:Norethindrone
vernacular_title: Estudio doble ciego con un anovulatorio oral. (Communicación preliminar)