Reduction of cervical resistance by prostaglandin suppositories prior to dilatation for induced abortion.

Several recent reports citing increased rates of prematurity among women who have had induced first-trimester abortion suggest that forceful cervical dilatation may result in cervical incompetence in future pregnancy. There appear to be conflicting clinical impressions regarding the effectiveness on cervical softening and the reduction of cervical resistance produced by various prostaglandins. The development of the Electronic Force Monitor which is capable of precise measurement of the forces encountered in overcoming resistance during dilatation provided objective evidence with which to evaluate the effects of vaginally administered prostaglandin E2 and F2alpha suppositories. Suppositories were administered 3 hours prior to cervical dilatation, after which suction curettage was performed. Compared to the nonmedicated control group, patients receiving PGF2alpha suppositories exhibited greatly reduced cervical resistance, in some cases permitting direct introduction of the suction curette without need for any preliminary dilatation. Those patients receiving PGE2 suppositories showed an intermediate degree of cervical softening.