Medical abortion with mifepristone and misoprostol usually involves an interval of 36–48 hours between administering these drugs; however, it is possible that the clinical efficacy at early gestations may be maintained when the drugs are taken simultaneously. The objective of this systematic review was to determine the safety and effectiveness of simultaneous compared with interval administration of mifepristone and misoprostol for abortion up to 10+0 weeks’ gestation.

Meta-analyses of three RCTs that included 1280 cases showed no differences in ‘ongoing pregnancy’, ‘hemorrhage requiring transfusion or ≥500 mL blood loss’, and ‘incomplete abortion with the need for surgical intervention’ between the interventions. Individual study results showed no difference in patient satisfaction, or ‘need for repeat misoprostol’, although ‘time to onset of bleeding or cramping’ was longer after simultaneous than interval administration. The quality of evidence was very low to moderate.

The study concluded to provide data that supports the use of simultaneous mifepristone and misoprostol for medical abortion up to 9+0 weeks in women who prefer this method of administration.

Reference: https://srh.bmj.com/content/46/4/270