A prospective multicenter, randomized trial was performed to evaluate if moistened misoprostol results in a more rapid abortion and a higher rate of complete abortion compared with dry misoprostol when adminsitered intravaginally for medical abortion after methotrexate. A total of 240 pregnant women =<49 days gestation seeking elective abortion received 50 mg/m 2 methotrexate intramuscularly followed 5-6 days later by 800 μg misoprostol vaginally. The misoprostol dose was repeated in 1-2 days if the abortion did not occur. Group 1 moistened the misoprostol before administration and group 2 used dry tablets. There was no statistically significant difference in the cumulative rate of abortion after the first misoprostol dose (73.0% vs 71.3%, p = 0.87), second misoprostol dose (84.1% vs 81.1%, p = 0.65), or by 35 days after methotrexate administration (95.2% vs 91.8%, p = 0.40) between groups 1 and 2, respectively. The proportion of subjects with embryonic cardiac activity 2 weeks after methotrexate injection was greater in group 2 (5.7%, 95% confidence interval [CI] 1.0%, 9.9%) than in group 1 (2.4%, 95% CI 0%, 5.0%), although not statistically significant (p = 0.21). The immediate succes rate in Pittsburgh was greater, albeit not statistically, for the women that moistened the misoprostol (87% vs 76%, p = 0.19); these rates were also not statistically different in Havana (82% vs 86%, p = 0.62). The rate of side effects after methotrexate was not different between groups but women in group 1 had significantly more diarrhea (36% vs 21%, p = 0.02) and fever/warmth/chills (44% vs 30%, p = 0.04). Moistening misoprostol before vaginal administration in a medical abortion regimen with methotrexate does not statistically improve efficacy. This trial demonstrates the importance of prospective, randomized studies to prove the relative efficacy of any medical abortion treatment regimen.