Preoperative cervical priming by intracervical application of a new sulprostone gel.

In a prospective, randomised dose-finding study involving 60 women scheduled for termination of 1st trimester pregnancy, 25 micrograms, 50 micrograms or 100 micrograms of a sulprostone gel with a constant injection volume of 2.5 ml were applied intracervically 6-8 hours before curettage. The gelatinising agent was Pluronic F 127, which is liquid at temperatures less than 20 degrees C but gelatinises immediately at body temperature. A sterile, ready-to-use gel can be produced within a minute by mixing the active substance with the gelatinising agent; this rules out any loss of activity due to storage of the substances. The priming effect was verified in 30 patients by means of comparative examinations with a special tonometer before application of the gel and immediately before the surgical procedure. The 100-micrograms dosage proved to be the most effective method in nulliparae, achieving a mean free patency (i.e. force less than 1 Newton) of 8.7 mm. In primiparae and multiparae, a comparable good effect was achieved with the 50-micrograms dose. After application of 25 micrograms sulprostone gel, the mean free patency was only 5.3 mm in the nulliparae and 8.5 mm in the primiparae and multiparae. The results of the tonometric studies agreed with the clinical documentation of the priming effect, which was assessed by means of a special score. The efficiency of the cervical priming correlated with the rate of vaginal bleeding and with the frequency of contraction-related lower abdominal pain. According to the present results, local application of this sulprostone gel represents a practicable and promising method for preoperative cervical priming because of its special electromechanical properties.