title: Comparison of cycle control with a combined contraceptive vaginal ring and oral levonorgestrel/ethinyl estradiol.
abstract: OBJECTIVE
  The purpose of this study was to compare cycle control and tolerability of the NuvaRing (NV Organon, Oss, The Netherlands), a novel combined contraceptive vaginal ring, with a standard combined oral contraceptive pill.
  
  
  METHODS
  Healthy women aged 18 to 40 years who requested contraception received either NuvaRing or a combined oral contraceptive containing 30 microg ethinyl estradiol and 150 microg levonorgestrel for 6 cycles in 3 similarly designed studies. Each cycle comprised 3 weeks of ring or pill use, followed by 1 ring- or pill-free week.
  
  
  RESULTS
  Two hundred forty-seven women began the studies, 121 women with NuvaRing and 126 women with the combined oral contraceptive. Withdrawal bleeding occurred in virtually all cycles in both groups. In the NuvaRing groups, the incidence of irregular bleeding was < or =5% in all cycles; this was lower than the combined oral contraceptive groups (5.4%-38.8%). Furthermore, the incidence of a normal intended bleeding pattern was significantly higher in the NuvaRing groups than in the combined oral contraceptive groups (P <.01). Both contraceptives were well tolerated.
  
  
  CONCLUSIONS
  NuvaRing has excellent cycle control and is well tolerated.
authors.affiliation: Department of Obstetrics and Gynecology, landspítalinn, Rekjavik, Iceland. rib@simnet.is
authors.forename: Ragnheidur I
authors.initials: RI
authors.lastname: Bjarnadóttir
authors.forename: Marjo
authors.initials: M
authors.lastname: Tuppurainen
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Killick
mesh_terms: D000284:Administration, Oral; D000328:Adult; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D003274:Contraceptive Devices, Female / Q000009:adverse effects; D003277:Contraceptives, Oral, Combined / Q000627:therapeutic use; D004338:Drug Combinations; D045166:Estradiol Congeners / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D004997:Ethinyl Estradiol / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D005260:Female; D006801:Humans; D015994:Incidence; D016912:Levonorgestrel / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D008597:Menstrual Cycle / Q000187:drug effects*; D014592:Uterine Hemorrhage / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology
chemical_list: D003271:Contraceptive Agents, Female; D003277:Contraceptives, Oral, Combined; D004338:Drug Combinations; D045166:Estradiol Congeners; D004997:Ethinyl Estradiol; D016912:Levonorgestrel