title: A prospective double-blinded, randomized, placebo-controlled trial on the use of letrozole pretreatment with misoprostol for second-trimester medical abortion.
abstract: BACKGROUND
  The aim of this randomized trial was to evaluate the abortion rate of combined regimen of letrozole and misoprostol in second-trimester abortion.
  
  
  METHODS
  This was a randomized, double-blinded, placebo-controlled trial of 130 women requesting legal termination of pregnancy at gestational age between 12 and 20 weeks. Letrozole 7.5 mg or placebo were given for 3 days, followed by misoprostol 400 mcg vaginally every 3 h up to a maximum of five doses on the third day.
  
  
  RESULTS
  The abortion rate in 24 and 48 h were similar for the letrozole and placebo groups (24 h: 93.8% vs. 90.8%, respectively, p=.718; 48 h: 98.5% vs. 95.4%, respectively, p=.496). The median induction-to-abortion interval was also similar for the letrozole and placebo groups (9.6 h vs. 10.6 h, p=.145). All the side effects were comparable between the two groups.
  
  
  CONCLUSIONS
  The use of letrozole pretreatment (7.5 mg daily for 3 days) with misoprostol in second-trimester abortion does not significantly improve the abortion rate of the misoprostol-only regimen.
authors.affiliation: Department of Obstetrics & Gynaecology, The University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China. v200lee@hku.hk
authors.forename: Vivian Chi Yan
authors.initials: VC
authors.lastname: Lee
authors.forename: Oi Shan
authors.initials: OS
authors.lastname: Tang
authors.forename: Ernest Hung Yu
authors.initials: EH
authors.lastname: Ng
authors.forename: William Shu Biu
authors.initials: WS
authors.lastname: Yeung
authors.forename: Pak Chung
authors.initials: PC
authors.lastname: Ho
mesh_terms: D000020:Abortifacient Agents, Nonsteroidal / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D000028:Abortion, Induced; D000328:Adult; D047072:Aromatase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination / Q000009:adverse effects; D005260:Female; D006785:Hospitals, University; D006801:Humans; D000077289:Letrozole; D016595:Misoprostol / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D009570:Nitriles / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D010865:Pilot Projects; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D013997:Time Factors; D014230:Triazoles / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D000020:Abortifacient Agents, Nonsteroidal; D047072:Aromatase Inhibitors; D009570:Nitriles; D014230:Triazoles; D016595:Misoprostol; D000077289:Letrozole