title: Cycle control with desogestrel-containing oral contraceptives--comparison of a monophasic and triphasic regimen.
abstract: OBJECTIVE
  To examine the effect of mono- and triphasic desogestrel-containing oral contraceptives on cycle control.
  
  
  METHODS
  Multicenter, international (U.S. and Canada).
  
  
  METHODS
  About 4,000 women, aged 18-35, healthy, neither pregnant nor lactating, were followed for almost 37,700 cycles of use of a monophasic 150 micrograms desogestrel/30 micrograms ethinyl estradiol OC or Sunday- or day-1 start regimens of a triphasic preparation containing 50/100/150 micrograms desogestrel/35/30/30 micrograms ethinyl estradiol administered on a 7/7/7 schedule. Standard diary methods were used to collect data on breakthrough bleeding, spotting, and absence of withdrawal bleeding.
  
  
  RESULTS
  The two formulations demonstrated very low and, in fact, remarkably similar rates of breakthrough bleeding, spotting, and absence of withdrawal bleeding. A statistical analysis of these characteristics of the total study populations, per cycle, revealed no statistically significant differences between the formulations.
  
  
  CONCLUSIONS
  Although the triphasic formulation contains the lowest estrogen dose of any triphasic available, 33% less progestin than the monophasic formulation, it maintains comparable cycle control.
authors.affiliation: Division of Reproductive Endocrinology, University of Texas, Dallas.
authors.forename: B R
authors.initials: BR
authors.lastname: Carr
mesh_terms: D000328:Adult; D003277:Contraceptives, Oral, Combined / Q000494:pharmacology* / Q000627:therapeutic use; D017135:Desogestrel / Q000009:adverse effects / Q000494:pharmacology* / Q000627:therapeutic use; D004997:Ethinyl Estradiol / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008597:Menstrual Cycle / Q000187:drug effects*; D014592:Uterine Hemorrhage / Q000139:chemically induced
chemical_list: D003277:Contraceptives, Oral, Combined; D004997:Ethinyl Estradiol; D017135:Desogestrel