Effect of Intramuscular Hyoscine-N-Butyl Bromide on Tubal Spasm and Pain Perception in Women with Infertility Undergoing Hysterosalpingography: A Randomised Controlled Trial

Background: A tubal patency test is essential in evaluating women with infertility. Hysterosalpingography (HSG) is the investigation of choice for assessing tubal patency. Objective: To evaluate the effect of intramuscular hyoscine-N-butyl bromide on tubal spasms and pain perception during hysterosalpingography. Methods: This randomized, controlled trial was conducted at the Radiology Departments and Infertility Clinics of four health institutions in Bayelsa State, Nigeria, between January 2021 and April 2022. Five hundred and twenty infertile women undergoing hysterosalpingography were randomized into two groups. Women in group I (control) received a placebo, while women in Group II (experimental) received 20 mg of intramuscular hyoscine-N-butyl bromide. Pain scores at different steps of the procedure were recorded. Results: The overall mean pain scores progressively decreased from contrast instillation (4.97 ± 2.08) through 30-minutes post-procedure (3.54 ± 1.54) to 24 hours post-procedure (1.96 ± 1.78). Pain scores at contrast instillation, 30 minutes and 24 hours after HSG were significantly lower in the hyoscine group compared to the placebo group (p = 0.001 each). There were significantly fewer women with tubal blockage in the hyoscine group compared to the placebo group [78 (30.0%) vs 131 (50.4%); p = 0.001]. Conclusion: Intramuscular hyoscine-N-butyl bromide before hysterosalpingography significantly reduces pain and tubal spasm during the procedure.