Background: Determining the optimal method of performing second-trimester abortions is important, since they account for a disproportionate amount of abortion-related morbidity and mortality.
Objectives: To compare surgical and medical methods of inducing abortion in the second trimester of pregnancy with regard to efficacy, side effects, adverse events, and acceptability.
Search strategy: We identified trials using Pub Med, EMBASE, POPLINE, and the Cochrane Central Register of Controlled Trials (CENTRAL). We also searched the reference lists of identified studies, relevant review articles, book chapters, and conference proceedings for additional, previously unidentified studies. We contacted experts in the field for information on other published or unpublished research.
Selection criteria: Randomised trials comparing any surgical to any medical method of inducing abortion at >/= 13 weeks' gestation were included.
Data collection and analysis: We assessed the validity of each study using the methods suggested in the Cochrane Handbook. Investigators were contacted as needed to provide additional information regarding trial conduct or outcomes. Two reviewers abstracted the data. Odds ratios and 95% confidence intervals were calculated for dichotomous variables using RevMan 4.2. The trials did not have uniform interventions, therefore, we were unable to combine them into a meta-analysis.
Main results: Two studies met criteria for this review. One compared dilation and evacuation (D&E) to intra-amniotic instillation of prostaglandin F(2) (alpha). The second study compared D&E to induction with mifepristone and misoprostol. Compared with prostaglandin instillation, the combined incidence of minor complications was lower with D&E (OR 0.17, 95% CI 0.04-0.65) as was the total number of minor and major complications (OR 0.12, 95% CI 0.03-0.46). The number of women experiencing adverse events was also lower with D&E than with mifepristone and misoprostol (OR 0.06, 95% CI 0.01-0.76). Although women treated with mifepristone and misoprostol reported significantly more pain than those undergoing D&E, efficacy and acceptability were the same in both groups. In both trials, fewer subjects randomised to D&E required overnight hospitalisation.
Authors' conclusions: Dilation and evacuation is superior to instillation of prostaglandin F(2) (alpha). The current evidence also appears to favour D&E over mifepristone and misoprostol, however larger randomised trials are needed.