Randomised controlled trial of the efficacy of misoprostol used as a cervical ripening agent prior to termination of pregnancy in the first trimester
Background. Misoprostol is being used increasingly in clinical practice for cervical ripening in first-trimester abortions, but because of lack of good evidence of its effectiveness, administration consensus has not been reached on dosage, route of administration, time of administration preoperatively and gestational age group. In this study we tested the hypothesis thatself-administration of 600 ug vaginal misoprostol is feasible and when used 2 - 4 hours preoperatively results in sufficient cervical dilatation to make suction curettage easier.
Methods. A double-blind, randomised, placebo-controlled trial was undertaken. Two hundred and seventy-eight women scheduled for termination of pregnancy of up to 12 weeks' duration by manual vacuum aspiration were assigned toreceive either 600 lig misoprostol pre-operatively, or placebo. The achievement of 'satisfactory' (≥7 mm) baseline cervical dilatation after 2 - 4 hours was evaluated as the primary outcome. Secondary outcome measurements included ease and duration of the procedure. Side-effects such as preoperative bleeding, gastro-intestinal complaints and pain as well as adverse events were noted in all cases.
Findings. Self-administration of vaginal misoprostol was successful in all women and 273 women were evaluated for main end-points. A significantly larger proportion of patients in the treatment group reached cervical dilatation of 2: 7 mm (67.3% v. 30.9%, P < 0.0001). The side-effects were minimal and comparable in the two groups. In the treatment group the mean procedure duration was significantly shorter (220 seconds v. 321 seconds, P = 0.0013) and ilie procedure was more likely to be rated by the operator as 'easy' (81.8%. v. 63.3%, P = 0.0082). This resulted in a significant reduction in treatment failure in the < 70-day gestation group (5.0% v. 14.7%, P = 0.005%
Conclusion. It is feasible, safe and effective for 600 lig misoprostol to be self-administered vaginally 2 - 4 hours pre-" operatively for cervical priming prior to manual vacuum aspiration. Further research is needed to establish optimal use in the first trimester and to determine patient acceptance.