Randomized trial of mifepristone and buccal or vaginal misoprostol for abortion through 56 days of last menstrual period.

Objective: Mifepristone-misoprostol medical abortion has been approved in the United States since 2000. U.S. providers have preferred to use vaginal misoprostol because of evidence that such a regimen is more effective in later gestations. Buccal administration of misoprostol may be equally effective and more acceptable to some women.

Methods: This open-label, randomized trial was conducted at two sites in Rochester, NY, and involved healthy women with pregnancies through 56 days since the last menstrual period (LMP) as indicated by sonogram. Women received mifepristone 200 mg orally and were randomized to use 800 mug of misoprostol either buccally or vaginally 1 to 2 days later. They returned within 15 days for repeat sonogram. If the woman's pregnancy had not been completely aborted by day 36, a suction abortion was performed. The primary outcome was a complete abortion without surgical intervention.

Results: Four hundred forty-two women were enrolled in the study, and complete data were available on 429. The efficacy rate was 95% (205/216) in the buccal group and 93% (199/213) in the vaginal group (chi(2)=0.43, p=.51). Nausea was the most commonly reported side effect, affecting 70% in the buccal group and 62% in the vaginal group. There were no differences in the satisfaction with the overall procedure between the buccal (92%) and the vaginal groups (95%) (chi(2)=1.87, p=.17).

Conclusion: Buccal administration of misoprostol after low-dose mifepristone for medical abortion appears to be a highly effective and acceptable alternative compared with vaginal administration for medical abortion in pregnancies through 56 days LMP.