title: A randomized double-blind trial of two low dose combined oral contraceptives.
abstract: Fifty-five women using Loestrin-20 (20 microgram ethinyl oestradiol and 1 mg norethisterone acetate) as an oral contraceptive have been compared with a like number using Microgynon-30 (30 microgram ethinyl oestradiol and 150 microgram levonorgestrel) in a randomized, double-blind trial. Despite the small sample size, the main finding in the trial is clear-cut; Loestrin-20 provides poor cycle control and is thus less acceptable as an oral contraceptive than Microgynon-30. Although there is also a suggestion that Loestrin-20 may be less effective than Microgynon-30, the difference in the accidental pregnancy rates is not statistically significant.
mesh_terms: D000293:Adolescent; D000328:Adult; D002986:Clinical Trials as Topic; D003276:Contraceptives, Oral / Q000008:administration & dosage*; D003277:Contraceptives, Oral, Combined / Q000008:administration & dosage*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004997:Ethinyl Estradiol / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008598:Menstruation; D009640:Norethindrone / Q000008:administration & dosage; D009644:Norgestrel / Q000008:administration & dosage; D011897:Random Allocation
chemical_list: D003276:Contraceptives, Oral; D003277:Contraceptives, Oral, Combined; D009644:Norgestrel; D004997:Ethinyl Estradiol; D009640:Norethindrone