title: Endometrial histology following 1 year of a continuous daily regimen of levonorgestrel 90 micro g/ethinyl estradiol 20 micro g.
abstract: OBJECTIVE
  The objective of this study was to evaluate the effect of a continuous daily regimen of levonorgestrel (LNG) 90 micro g/ethinyl estradiol (EE) 20 micro g on endometrial histology.
  
  
  METHODS
  This was a substudy of a large phase 3 trial conducted in six sites in North America. Healthy and sexually active women aged between 18 and 49 years took LNG 90 micro g/EE 20 micro g daily for 1 year. Results from endometrial biopsies performed at pretreatment baseline and those after at least 6 months of treatment were compared.
  
  
  RESULTS
  Of the 146 participants, 93 had a baseline biopsy and completed at least six pill packs. Before treatment, 56 subjects (60%) had an endometrial biopsy with findings classified as "weakly proliferative or proliferative." During the last on-therapy visit, 48 subjects (52%) had an endometrium categorized as "other," which included primarily an inactive or benign endometrium (n=42). No hyperplasia or malignancy was observed during the study.
  
  
  CONCLUSIONS
  The results of a 1-year continuous regimen of LNG 90 micro g/EE 20 micro g were shown to have a good endometrial safety profile.
authors.affiliation: Department of Obstetrics and Gynecology, University of Vermont College of Medicine, Burlington, VT 05401, USA.
authors.forename: Julia V
authors.initials: JV
authors.lastname: Johnson
authors.forename: Gary S
authors.initials: GS
authors.lastname: Grubb
authors.forename: Ginger D
authors.initials: GD
authors.lastname: Constantine
mesh_terms: D000293:Adolescent; D000328:Adult; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000009:adverse effects; D004717:Endometrium / Q000187:drug effects* / Q000473:pathology*; D004967:Estrogens / Q000008:administration & dosage / Q000009:adverse effects; D004997:Ethinyl Estradiol / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D016912:Levonorgestrel / Q000008:administration & dosage* / Q000009:adverse effects; D008796:Metrorrhagia / Q000517:prevention & control; D008875:Middle Aged; D012449:Safety; D016896:Treatment Outcome
chemical_list: D003271:Contraceptive Agents, Female; D004967:Estrogens; D004997:Ethinyl Estradiol; D016912:Levonorgestrel