Medical versus surgical methods for first trimester termination of pregnancy

Induced abortions are very commonly practiced interventions worldwide. A variety of medical abortion methods have been introduced during the last decade in addition to existing surgical methods. In this review we systematically searched for and combined all evidence from randomised controlled trials comparing surgical with medical abortion.

To evaluate medical methods in comparison to surgical methods for first-trimester abortion with respect to efficacy, side effects and acceptability.

The Cochrane Controlled Trials Register, MEDLINE (with the Cochrane 3-stage search strategy)(1966-2000) and Popline (1970-2000) were systematically searched. There were no language preferences in searching. Reference lists of retrieved papers were searched. Experts in WHO/HRP were contacted.

Randomised trials of any surgical abortion method compared with any medical abortion method in the first trimester.

Trial quality was assessed and data extraction was made independently by two reviewers.

Six studies mostly with small sample sizes, comparing 4 different interventions (prostaglandins alone, mifepristone alone, and mifepristone/misoprostol and methotrexate/misoprostol versus vacuum aspiration) were included. Results are sometimes based on one trial only. Prostaglandins vs vacuum aspiration: the rate of abortions not completed with the intended method was statistically significant higher in the prostaglandin group (2.7, 95% CI 1.1 to 6.8) compared to surgery. There are no data on the most commonly medical (mifepristone/misoprostol) and surgical abortion available to be included in the review. Duration of bleeding was longer in the medical abortion groups compared to vacuum aspiration. There was only one major complication (uterine perforation) in one trial in the surgical group. There was no difference between the groups for ongoing pregnancies at the time of follow-up or pelvic infections. No data on acceptability, side effects or women's satisfaction with the procedure were available for inclusion in the review.

The results are derived from relatively small trials. Prostaglandins used alone seems to be less effective and more painful compared to surgical first-trimester abortion. However, there is inadequate evidence to comment on the acceptability and side effects of medical compared to surgical first-trimester abortions. There is a need for trials to address the efficacy of currently used methods and women's preferences more reliably.