Medical abortion regimens: historical context and overview

Medical abortion offers an important alternative to surgical abortion for women with early pregnancies who wish to avoid a surgical procedure. More than 3 million women worldwide have had medical abortions in the past decade alone. The best-studied regimens include mifepristone orally followed 36 to 48 hours later by a prostaglandin analog administered either orally or intravaginally. Because of political and social restrictions related to mifepristone, however, researchers have investigated alternative regimens, most notably methotrexate and misoprostol. Mifepristone regimens are approximately 95% effective for abortion at