Comparison of the Effect of Letrozole and Misoprostol versus Misoprostol Alone on First Trimester Abortion

The need to perform an abortion in the first three months of pregnancy with an effective and safe drug therapy is more important than other methods. The purpose of this study is to compare the effects of letrozole and misoprostol versus misoprostol alone on abortion.

In this clinical trial, 114 candidates for legal abortion in the first trimester of pregnancy were randomly assigned to three groups of 38 people receiving sublingual misoprostol alone with placebo (same amount of letrozole), misoprostol with letrozole 10 mg daily for 3 days and the third group was given misoprostol along with letrozole with a daily dose of 5 mg for 3 days. In addition to the demographic and obstetrical information of the patients, the primary outcome including complete and incomplete abortion, misoprostol dosage and side effects were compared in patients of three groups.

The mean gestational age of the patients was 73.1±9.2 days. A total of 84 (73.7%) patients had complete abortion, including 28 patients (73.7%) in the letrozole 5 mg group, 32 patients (84.2%) in the letrozole 10 mg group, and 24 patients (63.2%) were in the placebo group. In the letrozole 10 mg group, with a statistically significant difference, the rate of complete abortion was higher in them than in the placebo group (84.2 vs. 63.2%, p=0.037). 20 patients in the letrozole 5 mg group, 16 in the letrozole 10 mg group, and all patients in the placebo group received misoprostol, and the difference between the two groups of letrozole 10 mg and placebo was significant in terms of misoprostol intake (p=0.001). The most common side effect in patients of all three groups was nausea and vomiting, which did not have a statistically significant difference between all three groups.

The findings of the present study showed that letrozole 10 mg along with misoprostol is effective in patients who need legal abortion in the first trimester.