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

Tang OS

Chan CC

Kan AS


Human Reproduction
Nov 2005


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.


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.


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.


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.