Mifepristone+misoprostol vs. misoprostol alone for early medical abortion

Abstract

Ngoc et al. [1], in their double-blind randomized placebocontrolled trial, show that mifepristone+misoprostol is more efficacious than misoprostol-only for early medical abortion. The study was conducted from August 2007 to March 2008 at a tertiary hospital in Vietnam. Using a misoprostol-only regimen, Ngoc et al. [1] report a complete abortion rate of 76.2% among 146 women, compared to 96.5% with mifepristone+misoprostol (n=194). The main finding of this study is consistent with previous trials, which have shown greater efficacy of combined regimens over single drugs [2]. However, this study does not provide a complete picture of misoprostolonly medical abortion regimens and the findings cannot be generalized to other settings. First, the authors acknowledge that there is no published evidence for the effectiveness of buccal misoprostol-only regimen. Current evidence supports vaginal administration over other routes; success rates of over 90% have been reported using moistened, vaginal misoprostol [3]. The use of buccal misoprostol may limit the generalizability of the findings to other misoprostol-only regimens. Second, dosing intervals used in this study may have been suboptimal. A study among 2066 women in six countries published in June 2007 [4] demonstrated that sublingual misoprostol achieved better efficacy (85%) if given every 3 h compared to every 12 h (83%). In the study by Ngoc et al. [1], misoprostol was administered every 24 h; although there are no published studies on buccal misoprostol for direct comparison, the authors note that the dosing interval of misoprostol may have negatively affected efficacy. The publication of the multicountry study by von Hertzen et al. [4] presented an opportunity for Ngoc et al. [1] to reconsider the regimen before data collection began. Finally, the authors' conclusions may cause confusion among abortion service providers and policy makers. The conclusion that “mifepristone + misoprostol regimens should be advocated [...] as the optimal early medical abortion method” could be interpreted as a call to move away from misoprostol-only regimens. While we must continue to advocate for greater access to mifepristone, there remain huge challenges to getting this abortifacient registered in restrictive settings. In contrast, misoprostol, which has several indications, is available much more widely. Movement away from provision of misoprostol-only regimens in restrictive settings would limit women's ability to access termination services, with potentially adverse consequences for women's health. Thoai D. Ngo Min Hae Park Research and Metrics Team Health System Department Marie Stopes International, London, UK Faculty of Epidemiology and Population Health London School of Hygiene and Tropical Medicine London, UK E-mail address: Thoai.Ngo@mariestopes.org