The study aimed to compare the efficacy and safety of sublingual and vaginal misoprostol for pregnancy termination in women with the first trimester missed abortion.

A single-blind, parallel-group, randomized clinical trial was conducted in a university hospital. All women who presented with the first trimester missed abortion were invited to participate in the study and were randomized to one of two groups: one group received sublingual misoprostol in three doses of 800 μg every four h. In contrast, a second group received vaginal misoprostol in the same dosage regimen. The study’s primary outcome was the rate of complete abortion within seven days after initiation of treatment.

The study included 200 women. The mean length of the induction–expulsion interval in the sublingual misoprostol group, was significantly shorter than the vaginal misoprostol group. The sublingual misoprostol group had a smaller drop in hemoglobin level. The side effects of misoprostol were substantially more frequent in the sublingual group compared with the vaginal group.

The study concluded that sublingual misoprostol is more effective than vaginal misoprostol in completing the first trimester missed abortion, with a shorter induction–expulsion time. However, sublingual misoprostol is associated with more side effects, such as unpleasant taste, gastrointestinal symptoms, and fever, compared with vaginal misoprostol.