A prospective randomized comparison of sublingual and oral misoprostol when combined with mifepristone for medical abortion at 12-20 weeks gestation

Hum Reprod. 2005 Nov;20(11):3062-6. doi: 10.1093/humrep/dei196. Epub 2005 Jul 21.


Background: Sublingual misoprostol has been shown to be effective in medical abortion. A prospective double-blinded placebo-controlled trial was done to compare the efficacy and side-effects of sublingual to oral misoprostol when used with mifepristone for medical abortion from 12 to 20 weeks gestation.

Methods: A total of 120 women at 12-20 weeks of gestation were randomized to receive 200 mg oral mifepristone followed by either sublingual or oral misoprostol 400 mg every 3 h for a maximum of five doses 36-48 h later. The course of misoprostol was repeated if the woman did not abort within 24 h.

Results: There was no significant difference (P = 0.43) in the success rate at 24 h [relative risk = 1.075; 95% confidence interval (CI): 0.94-1.19]. Abortion occurred in 91.4% in the sublingual group (95% CI: 81.0-96.7%) as compared to 85.0% (95% CI: 73.7-92.1%) in the oral group. The median induction-to-abortion interval was significantly shorter (P = 0.009) in the sublingual group (5.5 h) as compared to the oral group (7.5 h). The incidence of fever was higher in the sublingual group (P < 0.0001). The incidences of other side-effects were similar.

Conclusion: Sublingual misoprostol, when combined with mifepristone, is effective for medical abortion in the second trimester. The induction-to-abortion interval is shorter when sublingual misoprostol is used when compared to oral misoprostol.

Publication types

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

MeSH terms

  • Abortifacient Agents, Nonsteroidal / administration & dosage
  • Abortion, Induced / methods*
  • Administration, Oral
  • Administration, Sublingual
  • Adult
  • Double-Blind Method
  • Drug Therapy, Combination
  • Female
  • Humans
  • Mifepristone / administration & dosage*
  • Misoprostol / administration & dosage*
  • Misoprostol / adverse effects
  • Pregnancy
  • Pregnancy Trimester, Second*
  • Prospective Studies


  • Abortifacient Agents, Nonsteroidal
  • Misoprostol
  • Mifepristone