title: Randomized cross-over study of a 21-day versus a 28-day hormone replacement therapy (HRT).
abstract: OBJECTIVE
  To compare the occurrence of climacteric symptoms at two points in the cycle, identified as minE (phase of minimum estrogen effect) and MaxP (phase of maximum progesterone effect).
  
  
  METHODS
  Prospective randomized cross-over study in postmenopausal women currently on HRT comparing two opposed, sequential formulations: a regimen of 21 tablets containing estradiol valerate (EV) opposed with cyproterone acetate (CPA) in the last 10 tablets, versus a regimen of 28 tablets of conjugated equine estrogens (CEE), the last 12 tablets of which were taken together with norgestrel (NG).
  
  
  METHODS
  Incidence of 24 climacteric complaints assessed at the specified days of the cycle corresponding to minE (day 6 or 7) and MaxP (day 27 or 28)
  
  
  RESULTS
  Contrary to the hypothesis that estrogen-dependent symptoms will recur at minE of the 21-day regimen, no significant differences were noted with the regimen containing 28 days of CEE, which served as the control. There were more complaints with the CEE+NG formulation at both minE and MaxP. Of the 38 patients, 63% preferred the EV+CPA regimen, 18.4% the CEE+NG regimen and 18.4% rated both preparations as equal.
  
  
  CONCLUSIONS
  The 7-day pause in the 21-day formulation containing EV+CPA did not affect efficacy; it was as effective in relieving climacteric symptoms as the regimen containing 28 days of estrogen. Based on the frequency of complaints both at minE and MaxP, the EV+CPA formulation induced a more acceptable symptom and mood profile.
authors.affiliation: Department of Obstetrics and Gynecology, National University Singapore.
authors.forename: T
authors.initials: T
authors.lastname: McCarthy
authors.forename: V
authors.initials: V
authors.lastname: Dramusic
authors.forename: R
authors.initials: R
authors.lastname: Carter
authors.forename: A
authors.initials: A
authors.lastname: Costales
authors.forename: S S
authors.initials: SS
authors.lastname: Ratnam
mesh_terms: D000328:Adult; D002979:Climacteric / Q000187:drug effects*; D018592:Cross-Over Studies; D017373:Cyproterone Acetate / Q000008:administration & dosage* / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004958:Estradiol / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D015914:Estrogen Replacement Therapy / Q000379:methods*; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D008875:Middle Aged; D009644:Norgestrel / Q000008:administration & dosage* / Q000009:adverse effects; D017060:Patient Satisfaction; D016896:Treatment Outcome
chemical_list: D004966:Estrogens, Conjugated (USP); D009644:Norgestrel; D017373:Cyproterone Acetate; D004958:Estradiol