Abstract
BACKGROUND: Effective cervical preparation is crucial for procedures requiring transcervical uterine access. Insufficient dilation can complicate these interventions. While chemical agents are commonly used, the optimal method remains under investigation. OBJECTIVE: This study aimed to compare the effectiveness and safety of vaginal hyoscine butylbromide vs vaginal misoprostol for cervical preparation prior to gynecological intrauterine surgery. METHODS: This double-blind, randomized controlled trial included 71 women scheduled for gynecological intrauterine interventions requiring cervical preparation. Participants were randomly assigned to receive either vaginal hyoscine butylbromide (n=36, 40 mg total dose) or vaginal misoprostol (n=35, 200 µg) 2 to 4 hours before the procedure. The primary outcome was the diameter of the first Hegar dilator that could be inserted through the internal os without resistance. Secondary outcomes included cervicovaginal-uterine complications and drug-related side effects. RESULTS: The mean diameter of the first dilator passed without force was (4.91±1.10) mm in the hyoscine group and (5.54±1.50) mm in the misoprostol group; this difference was not statistically significant (P=.081). Notably, the incidence of uterine pain and cramping was significantly lower in the hyoscine group (0% vs 34.3%, P<.001), representing a key clinical advantage. No significant differences were observed in other complications or side effects between the groups. No cases of uterine or cervical rupture occurred. CONCLUSION: Vaginal hyoscine butylbromide demonstrated comparable cervical dilation to misoprostol but resulted in significantly less uterine pain and cramping, which constitutes a meaningful clinical advantage. The complete elimination of uterine cramping in the hyoscine group highlights its distinct benefit as a cervical priming agent. Hyoscine appears to be a safe and more comfortable option for cervical preparation in premenopausal women undergoing gynecological procedures.