title: Comparison of uterine concentrations of ethinyl estradiol and etonogestrel after use of a contraceptive vaginal ring and an oral contraceptive.
abstract: OBJECTIVE
  To compare uterine tissue concentrations of ethinyl estradiol (EE) and etonogestrel (ENG) after one cycle of use of a contraceptive vaginal ring (NuvaRing; NV Organon, Oss, The Netherlands) or a combined oral contraceptive (COC).
  
  
  METHODS
  Randomized, open-label, pharmacokinetic study.
  
  
  METHODS
  Obstetrics and gynecology unit.
  
  
  METHODS
  Eight premenopausal women about to undergo hysterectomy but otherwise healthy.
  
  
  METHODS
  One cycle (17-21 days) of NuvaRing or COC treatment that ended with surgical hysterectomy.
  
  
  METHODS
  Tissue concentrations of EE and ENG in uterine tissue samples taken from the upper myometrium and mid-myometrium, the cervical region, and the endometrium.
  
  
  RESULTS
  In both groups, concentrations of EE and ENG were similar in uterine tissue taken from the upper myometrium and mid-myometrium and the cervical region. However, compared with the COC group, concentrations of both hormones were markedly lower in tissue samples from the endometrium of women who had been treated with NuvaRing.
  
  
  CONCLUSIONS
  Vaginal administration of hormones with NuvaRing did not produce elevated uterine concentrations of EE and ENG, compared with an oral contraceptive.
authors.affiliation: Department of Obstetrics and Gynecology, Atrium Medisch Centrum, Heerlen, The Netherlands.
authors.forename: Frans J M E
authors.initials: FJ
authors.lastname: Roumen
authors.forename: Thom O M
authors.initials: TO
authors.lastname: Dieben
mesh_terms: D000282:Administration, Intravaginal; D000328:Adult; D003274:Contraceptive Devices, Female; D003277:Contraceptives, Oral, Combined / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D017135:Desogestrel / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D004967:Estrogens / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D004997:Ethinyl Estradiol / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007044:Hysterectomy; D008875:Middle Aged; D045167:Progesterone Congeners / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics; D014018:Tissue Distribution; D014599:Uterus / Q000601:surgery
chemical_list: D003277:Contraceptives, Oral, Combined; D004967:Estrogens; D045167:Progesterone Congeners; C044815:etonogestrel; D004997:Ethinyl Estradiol; D017135:Desogestrel