title: Effects on cycle control and bodyweight of the combined contraceptive ring, NuvaRing, versus an oral contraceptive containing 30 microg ethinyl estradiol and 3 mg drospirenone.
abstract: BACKGROUND
  The objective of this study was to compare cycle control, cycle-related characteristics and bodyweight effects of NuvaRing with those of a combined oral contraceptive (COC) containing 30 microg of ethinyl estradiol and 3 mg of drospirenone.
  
  
  METHODS
  A randomized, multicentre, open-label trial in which 983 women were treated (intent-to-treat population) with NuvaRing or the COC for 13 cycles.
  
  
  RESULTS
  Breakthrough bleeding or spotting during cycles 2-13 was in general less frequent with NuvaRing than that with the COC (4.7-10.4%) and showed a statistically significant odds ratio of 0.61 (95% confidence interval: 0.46, 0.80) with longitudinal analysis. Intended bleeding was significantly better for all cycles with NuvaRing (55.2-68.5%) than that with the COC (35.6-56.6%) (P < 0.01). Changes from baseline in mean bodyweight and body composition parameters were relatively small for both groups with no notable between-group differences.
  
  
  CONCLUSIONS
  NuvaRing was associated with better cycle control than the COC, and there was no clinically relevant difference between the two groups in bodyweight.
authors.affiliation: Department of Obstetrics and Gynaecology, Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. ian.milsom@obgyn.gu.se
authors.forename: I
authors.initials: I
authors.lastname: Milsom
authors.forename: I
authors.initials: I
authors.lastname: Lete
authors.forename: A
authors.initials: A
authors.lastname: Bjertnaes
authors.forename: K
authors.initials: K
authors.lastname: Rokstad
authors.forename: I
authors.initials: I
authors.lastname: Lindh
authors.forename: C J
authors.initials: CJ
authors.lastname: Gruber
authors.forename: M H
authors.initials: MH
authors.lastname: Birkhäuser
authors.forename: E
authors.initials: E
authors.lastname: Aubeny
authors.forename: T
authors.initials: T
authors.lastname: Knudsen
authors.forename: C
authors.initials: C
authors.lastname: Bastianelli
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000736:Androstenes / Q000008:administration & dosage*; D001823:Body Composition; D001835:Body Weight; D003274:Contraceptive Devices, Female; D003276:Contraceptives, Oral / Q000627:therapeutic use*; D017135:Desogestrel / Q000008:administration & dosage* / Q000031:analogs & derivatives; D004338:Drug Combinations; D004997:Ethinyl Estradiol / Q000008:administration & dosage*; D006801:Humans; D007434:Intrauterine Devices; D008597:Menstrual Cycle / Q000187:drug effects*; D010349:Patient Compliance
chemical_list: D000736:Androstenes; D003276:Contraceptives, Oral; D004338:Drug Combinations; C516519:NuvaRing; C044815:etonogestrel; D004997:Ethinyl Estradiol; D017135:Desogestrel; C035144:drospirenone