To compare the outcomes of 4 different perioperative misoprostol regimens for surgical termination of first-trimester pregnancy.Retrospective analysis of the records of 4000 women (4 cohorts of 1000 each) who underwent surgical termination of pregnancy. The 4 cohorts received: no misoprostol; 200μg of oral misoprostol 30 minutes preoperatively; 200μg of sublingual misoprostol 30 minutes preoperatively; or 200μg of oral misoprostol 3 hours preoperatively plus 200μg of vaginal misoprostol postoperatively. Adverse effects of the last regimen were surveyed in 1000 women.In the cohorts that received misoprostol, the difficulty of cervical dilatation was reduced (P<0.001) compared with the cohort of women that did not receive misoprostol. The frequency with which women made postoperative contacts with the clinic was also reduced in the cohorts that received misoprostol (P<0.05). Adverse effects were minimal.This retrospective study showed an association between perioperative administration of misoprostol, reduced difficulty for operators, and reduced demand for postoperative care. The regimen associated with the greatest reduction in difficult cervical dilatations and postoperative consultations was 200μg of oral misoprostol 3 hours preoperatively plus 200μg of misoprostol vaginally at the end of the surgical procedure.