title: Evaluation of an ultra-low-dose oral contraceptive for dysmenorrhea: a placebo-controlled, double-blind, randomized trial.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of an ultra-low-dose oral contraceptive (NPC-01; 0.02 mg ethinyl estradiol and 1 mg norethisterone) in subjects with dysmenorrhea.
  
  
  METHODS
  Placebo-controlled, double-blind, randomized trial.
  
  
  METHODS
  Clinical trial sites.
  
  
  METHODS
  Two hundred fifteen subjects with dysmenorrhea.
  
  
  METHODS
  Subjects were randomly assigned to receive NPC-01, placebo, or IKH-01 (0.035 mg ethinyl estradiol and 1 mg norethisterone) for four cycles.
  
  
  METHODS
  Total dysmenorrhea score (verbal rating scale) assessing pain on the basis of limited ability to work and need for analgesics.
  
  
  RESULTS
  The reductions of total dysmenorrhea score and visual analog scale score after the treatment were significantly higher in the NPC-01 group than in the placebo group. Furthermore, the efficacy of NPC-01 was comparable to that of IKH-01. The overall incidence of side effects was significantly higher in the NPC-01 group than in the placebo group. All side effects that occurred in the NPC-01 group were previously reported in patients receiving IKH-01. No serious side effects occurred.
  
  
  CONCLUSIONS
  The ultra-low-dose contraceptive NPC-01 relieved dysmenorrhea as effectively as IKH-01. Thus, NPC-01 could represent a new option for long-term treatment of dysmenorrhea.
  NCT01129102.
authors.affiliation: Department of Obstetrics and Gynecology, Tottori University School of Medicine, Tottori, Japan. Electronic address: tasuku@grape.med.tottori-u.ac.jp.
authors.forename: Tasuku
authors.initials: T
authors.lastname: Harada
authors.affiliation: Department of Integrated Women's Health, St. Luke's International Hospital, Tokyo, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Momoeda
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000700:Analgesics / Q000627:therapeutic use; D003277:Contraceptives, Oral, Combined / Q000008:administration & dosage* / Q000009:adverse effects; D003278:Contraceptives, Oral, Hormonal / Q000008:administration & dosage* / Q000009:adverse effects; D004311:Double-Blind Method; D004412:Dysmenorrhea / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D004997:Ethinyl Estradiol / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D007564:Japan; D008597:Menstrual Cycle / Q000187:drug effects*; D009640:Norethindrone / Q000008:administration & dosage* / Q000009:adverse effects; D010147:Pain Measurement; D013997:Time Factors; D016896:Treatment Outcome; D014938:Work Capacity Evaluation; D055815:Young Adult
chemical_list: D000700:Analgesics; D003277:Contraceptives, Oral, Combined; D003278:Contraceptives, Oral, Hormonal; D004997:Ethinyl Estradiol; D009640:Norethindrone
keywords: Ultra-low-dose oral contraceptives; dysmenorrhea; placebo-controlled randomized trial