Effectiveness of early medical abortion using low-dose mifepristone and buccal misoprostol in women with no defined intrauterine gestational sac

Background: The study was conducted to assess the effectiveness of early medical abortion (EMA) in women with early pregnancy and no defined intrauterine gestational sac (IUGS) on ultrasound. Study Design: Retrospective, multicenter, observational study of oral mifepristone 200 mg and buccal misoprostol 800 mcg administered 24-48 h later for EMA (gestations <= 63 days). Odds ratios (ORs) [95% confidence intervals (Cis)] of EMA failure and continuing pregnancy for women with no defined TUGS vs. those with confirmed IUGS were calculated. Results: Women with no defined JUGS were more likely to experience EMA failure [9.0% (6/67) vs. 3.5% (465/13,345); OR (95% CI)=2.72 (1.17-6.33), p=.041] and continuing pregnancy [7.5% (5/67) vs. 0.6% (83/13,345); OR (95% CI)=12.72 (4.98-32.46), p9.001]. Conclusion: EMA failure is more likely in women with early pregnancy and no defined IUGS than those with gestations <= 63 days and confirmed JUGS. Trial Registration: Australian New Zealand Clinical Trials Registry identifier: ACTRN12611001051932. (C) 2013 Elsevier Inc. All rights reserved.