Objective: To compare the efficacy and adverse effects of 400 µg intravaginal misoprostol for second-trimester pregnancy termination in live fetuses between two groups: one in which misoprostol was moistened with normal saline solution (NSS) and the other in which misoprostol was moistened with acetic acid.

Materials and Methods: A total of 179 pregnant women between 14 and 28 weeks of gestation with live fetuses indicated for pregnancy termination were recruited. They were randomly allocated to receive 400 µg intravaginal misoprostol either moistened with NSS (n = 96) or moistened with acetic acid (n = 83). The same dosage was then repeated every 3 h if adequate uterine contractions were not achieved until 48 h after the initiation of misoprostol. The main outcomes were mean abortion time, success rate, and adverse effects.

Results: The mean abortion time was not significantly different between the groups (24.98 ± 16.42 h vs 25.89 ± 10.34 h, P > 0.05). The rates of abortion within 24 h and 48 h and the adverse effects were also comparable between the groups. Chills and fever were the most common adverse effects in this study.

Conclusion: Intravaginal misoprostol either moistened with NSS or acetic acid was comparable in terms of efficacy and adverse effects.