title: Superior cycle control with a contraceptive vaginal ring compared with an oral contraceptive containing 30 microg ethinylestradiol and 150 microg levonorgestrel: a randomized trial.
abstract: BACKGROUND
  This trial was conducted to compare cycle control with vaginal ring a combined contraceptive vaginal ring, and a combined oral contraceptive (COC) delivering 30 mug ethinylestradiol (EE) and 150 mug levonorgestrel.
  
  
  METHODS
  This open-label, randomized, multi-centre, Phase III study involved adult women from 11 countries. Subjects were treated with either vaginal ring or a COC for 13 cycles (12 months).
  
  
  RESULTS
  A total of 1030 subjects (vaginal ring, n=512; COC, n=518) comprised the intention-to-treat (ITT) population. The percentage of women in the ITT population who completed the trial was 70.9% for vaginal ring and 71.2% for the COC group. The incidence of breakthrough bleeding and spotting over cycles 2-13, the primary efficacy parameter, was lower with vaginal ring (range 2.0-6.4%) than the COC (range 3.5-12.6%), and for cycles 2 and 9 the lower incidence with vaginal ring was confirmed as statistically significant (P=0.003 and P=0.002 respectively). The incidence of intended bleeding was significantly higher over all cycles with vaginal ring (58.8-72.8%) than with the COC (43.4-57.9%).
  
  
  CONCLUSIONS
  Cycle control with vaginal ring was excellent and superior to that of a COC containing 30 mug EE.
authors.affiliation: Women's Health Associates, Kopavogur, Iceland.
authors.forename: K
authors.initials: K
authors.lastname: Oddsson
authors.forename: B
authors.initials: B
authors.lastname: Leifels-Fischer
authors.forename: D
authors.initials: D
authors.lastname: Wiel-Masson
authors.forename: N R
authors.initials: NR
authors.lastname: de Melo
authors.forename: C
authors.initials: C
authors.lastname: Benedetto
authors.forename: C H J
authors.initials: CH
authors.lastname: Verhoeven
authors.forename: T O M
authors.initials: TO
authors.lastname: Dieben
mesh_terms: D000328:Adult; D003274:Contraceptive Devices, Female / Q000009:adverse effects; D003280:Contraceptives, Oral, Synthetic / Q000008:administration & dosage* / Q000009:adverse effects; D004967:Estrogens / Q000008:administration & dosage* / Q000009:adverse effects; D004997:Ethinyl Estradiol / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D015994:Incidence; D016912:Levonorgestrel / Q000008:administration & dosage* / Q000009:adverse effects; D008597:Menstrual Cycle / Q000187:drug effects; D010349:Patient Compliance; D011247:Pregnancy; D018873:Pregnancy Rate; D014592:Uterine Hemorrhage / Q000453:epidemiology
chemical_list: D003280:Contraceptives, Oral, Synthetic; D004967:Estrogens; D004997:Ethinyl Estradiol; D016912:Levonorgestrel