A randomized controlled trial of fentanyl for abortion pain

OBJECTIVE: Our aim was to find out whether intravenous fentanyl was effecti ve in reducing the pain of first-trimester abortion. STUDY DESIGN: This randomized controlled trial included 825 women attending a nonhospital abortion facility. Some women chose standard care. Women who did not choose standard care were randomly assigned to receive either 50 t o 100 tg of fentanyl, a placebo, or no intervention. With SAS software and a mixed effects analysis of variance model with covariates, we compared mea n pain scores of the fentanyl and placebo groups to detect a difference of at least 1 point on an 11-point pain scale. RESULTS: The mean pain score of the fentanyl group was 1.0 point less than that of the placebo group (95% confidence interval, 3.7-4.3) and 0.9 point less than that of the observational group (95% confidence interval, 4.7-5.1 ). This pain reduction was statistically significant, but the women who wer e studied wanted a 2-point reduction from fentanyl. CONCLUSION: Fentanyl, when compared with the placebo, reduced abortion pain by 1.0 point on an 11-point scale. This reduction was of questionable clin ical significance and was less than desired by the women included in the st udy.