<p><strong>Background: </strong>Tubal factor is responsible for most of the causes of infertility, especially in our environment, and hysterosalpingography (HSG) is the investigation of choice for assessing tubal patency.<strong> </strong>Objective of current study was to evaluate the effect of the addition of intramuscular hyoscine-N-butyl bromide (HBB) to local and systemic analgesics on pain perception during hysterosalpingography.<strong></strong></p><p><strong>Methods: </strong>This randomized controlled trial was conducted at the radiology departments and infertility clinics of four health institutions in Bayelsa State, Nigeria, from January 2020 to April 2022. One thousand and forty infertile women undergoing hysterosalpingography were randomized into four groups, and each group administered four different pain relief methods. Pain scores at different steps of the procedure were recorded. Data were analysed using the Statistical Product and Service Solutions for Windows®, version 25. Student’s t-test was used to compare sample means, while the chi-square test was used to compare the proportion of women in the two study groups, who expressed pain during the procedure.</p><p><strong>Results: </strong>The Paracervical block+HBB appeared to the most effective agent for pain relief in the study as women receiving this medication indicated the least pain intensity scores at all levels of the procedure except at the insertion of the speculum. The differences observed in the indicated pain intensity scores were also statistically significant (p<0.05).<strong></strong></p><p><strong>Conclusions: </strong>Our study revealed that adding HBB, an antispasmodic agent, to diclofenac and paracervical block significantly reduces pain perception during HSG compared to using diclofenac and paracervical block alone.</p>