title: Comparison of a transdermal continuous combined and an interrupted progestogen HRT.
abstract: OBJECTIVE
  Pilot study to compare the effects of a continuous combined hormone replacement therapy (HRT) regimen with an interrupted progestogen regimen administered transdermally, upon the endometrium of postmenopausal women, the incidence of amenorrhoea and relief of menopausal symptoms.
  
  
  METHODS
  Fifty-nine postmenopausal women aged 50-63 years were randomised to either (i) continuous combined regimen: combined oestrogen/progestogen skin patches (releasing continuous 50 microg estradiol and 20 microg levonorgestrel/day) or (ii) interrupted regimen: oestrogen-only patches (releasing 80 microg estradiol/day) for 4 days followed by combined oestrogen/progestogen patches (releasing continuous 50 microg estradiol and 20 microg levonorgestrel/day) for 3 days, for 6 months. An endometrial biopsy was performed at end of treatment for histological analysis.
  
  
  RESULTS
  Thirty-three women (56%) completed the study. Significantly higher rates of amenorrhoea were observed with the interrupted than continuous combined regimen (P<0.0001; 25% versus 7% at 6 months). The interrupted regimen was also associated with fewer days of bleeding overall (total 20 versus 44 days during months 4-6; P=0.001). Both regimens improved vasomotor symptoms. No endometrial hyperplasia or atypical changes were observed in endometrial biopsies.
  
  
  CONCLUSIONS
  Although significantly less bleeding was observed with the interrupted regimen, it did not have a sufficiently high incidence of amenorrhoea to render it clinically useful.
authors.affiliation: Department of Reproductive and Developmental Sciences, Division of Obstetrics and Gynaecology, University of Edinburgh, Centre for Reproductive Biology, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SU, UK.
authors.forename: Sharon T
authors.initials: ST
authors.lastname: Cameron
authors.forename: Anna F
authors.initials: AF
authors.lastname: Glasier
authors.forename: Ailsa
authors.initials: A
authors.lastname: Gebbie
authors.forename: Helen
authors.initials: H
authors.lastname: Dewart
authors.forename: David T
authors.initials: DT
authors.lastname: Baird
mesh_terms: D000279:Administration, Cutaneous; D000568:Amenorrhea / Q000453:epidemiology; D004359:Drug Therapy, Combination; D004717:Endometrium / Q000187:drug effects*; D004958:Estradiol / Q000008:administration & dosage*; D015914:Estrogen Replacement Therapy / Q000009:adverse effects / Q000379:methods*; D005260:Female; D019584:Hot Flashes / Q000188:drug therapy; D006801:Humans; D015994:Incidence; D016912:Levonorgestrel / Q000008:administration & dosage*; D008875:Middle Aged; D010865:Pilot Projects; D017698:Postmenopause / Q000187:drug effects*; D016896:Treatment Outcome; D014592:Uterine Hemorrhage / Q000139:chemically induced / Q000453:epidemiology
chemical_list: D004958:Estradiol; D016912:Levonorgestrel