RESUMEN
INTRODUCTION: Pain experience, physical reaction, image quality and adverse events during Gel Instillation Sonohysterography (GIS) can differ using gels with different compositions. As a result, patient satisfaction can also be affected. The effect of two instillation gels, Endosgel versus ExEmgel, using both the Visual Analogue Scale (VAS) and a Continuous Pain Score Meter (CPSM) was therefore compared. METHODS: This single centre double blind randomised controlled trial included 80 women planned for outpatient GIS, diagnosed with abnormal intrauterine bleeding or fertility disorders and suspicion on an intrauterine abnormality. Patients were randomly allocated to the instillation of Endosgel containing chlorhexidine or ExEmgel without chlorhexidine. Primary outcome was reported pain during the procedure using VAS. Secondary outcomes included pain score measured using CPSM, satisfaction to the procedure and preference at 3 weeks and 3 months after the procedure and image quality. A cost benefit analysis was also performed. RESULTS: The reported median VAS concerning pain during gel instillation was comparable in the Endosgel and ExEmgel group, 2.50 (IQR 0.00-5.00) and 2.00 (IQR 0.00-5.75) respectively (p = 0.69). The median VAS of the entire procedure was also similar: both 2.00 (IQR 0.00-5.00) (p = 0.86). CPSM-scores were not significantly different either. Both groups were similar in image quality (p = 0.83) and patient's satisfaction (p = 0.36). CONCLUSION: Concerning the pain experienced during a GIS procedure and patients' satisfaction, the ExEmgel was not proven to be superior to the Endosgel. Our advice is to use the gel that is available at the lowest costs, as the image quality is the same for both Endosgel and ExEmgel.