COMPARISON OF MIFEPRISTONE REGIMENS

Adapted from FDA Package Label 2016,  NAF CPG 2016, and Reproductive Health Access Project

Factor Evidence-Based Regimens Based on evidence up to 2016
Vaginal Miso Buccal Miso Sublingual Miso
Gestational Age Limit ≤ 70 days
Mifepristone Dose (Day 1) 200 mg orally
Misoprostol Dose & Route 800 mcg vaginal 800 mcg buccal 400 to 800 mcg sublingual
Timing of Misoprostol Administration 0-48 hours after mifepristone 24-48 hours after mifepristone 24-48 hours after mifepristone
Follow-Up Assessment Day 2 – 14
(NAF CPG suggests Day 7 – 14)
Success Rate (not requiring aspiration) 95-98% 95-99% (up to 63d)
91-93% (64-70d)
95% (up to 63d)
92% (64-70d)
Core References Creinin 2007,
Creinin 2004,
Schaff 1999, 2002
Ashok 1998
Danco 2016, Gatter 2015,
Sanhueza Smith 2015,
Winikoff 2012,
Boersma 2011,
Middleton 2005
Bracken 2014,
Chai 2013,
Tang 2003

1. Updated FDA regimen as of March 2016.
2. Primary studies demonstrating efficacy from 64-70 days used buccal misoprostol regimens, but vaginal and buccal routes are similar in efficacy. (NAF Online 2016).
3. Limited data demonstrates the same efficacy of a lower dose of sublingual misoprostol with fewer side effects, 400 vs. 800 mcg 24-48 hours after mifepristone (Bracken 2014).
4. A repeat dose of misoprostol may be required.

The FDA approved mifepristone with misoprostol for medication abortion in 2000, using a specific regimen based on evidence collected through 1998: mifepristone 600 mg followed 48 hours later by misoprostol 400 mcg orally, with a gestational age limit of 49 days. Since then, ongoing studies have delineated improved evidence-based regimens with optimized efficacy, convenience, and side effects.  The updated 2016 FDA labeling for mifepristone reflects the newer data using 200 mg of mifepristone followed by buccal misoprostol as noted above.

Internationally, particularly in countries with restrictive abortion laws, misoprostol has been used alone for early abortion. Most studies show an efficacy range between 75% and 90% without a need for surgical intervention in pregnancies up to 63 days gestation. The regimens used include 3 doses of 800 mcg of vaginal or buccal misoprostol 3 to 12 hours apart (Von Hertzen 2007, Gynuity 2013). More information about regimens is available at Gynuity.

Methotrexate 50 mg/m2 is occasionally used when the diagnosis of EPL versus ectopic is indeterminate. Unlike mifepristone, methotrexate is an effective treatment for early ectopic pregnancy. Efficacy is determined with serial hCG testing, clinical exams and progression of signs and symptoms (Seeber 2006).