A prospective double-blinded, randomized, placebo-controlled trial on the use of letrozole pretreatment with misoprostol for second-trimester medical abortion

Contraception. 2011 Dec;84(6):628-33. doi: 10.1016/j.contraception.2011.03.012. Epub 2011 May 4.

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.

Study design: 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.

Conclusion: 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.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abortifacient Agents, Nonsteroidal / administration & dosage
  • Abortifacient Agents, Nonsteroidal / adverse effects
  • Abortifacient Agents, Nonsteroidal / pharmacology*
  • Abortion, Induced*
  • Adult
  • Aromatase Inhibitors / administration & dosage
  • Aromatase Inhibitors / adverse effects
  • Aromatase Inhibitors / pharmacology*
  • Double-Blind Method
  • Drug Administration Schedule
  • Drug Therapy, Combination / adverse effects
  • Female
  • Hospitals, University
  • Humans
  • Letrozole
  • Misoprostol / administration & dosage
  • Misoprostol / adverse effects
  • Misoprostol / pharmacology*
  • Nitriles / administration & dosage
  • Nitriles / adverse effects
  • Nitriles / pharmacology*
  • Pilot Projects
  • Pregnancy
  • Pregnancy Trimester, First
  • Pregnancy Trimester, Second
  • Time Factors
  • Triazoles / administration & dosage
  • Triazoles / adverse effects
  • Triazoles / pharmacology*
  • Young Adult

Substances

  • Abortifacient Agents, Nonsteroidal
  • Aromatase Inhibitors
  • Nitriles
  • Triazoles
  • Misoprostol
  • Letrozole