Office hysteroscopy and compliance: mini-hysteroscopy versus traditional hysteroscopy in a randomized trial.

Background: Diagnostic hysteroscopy has not yet been generally accepted as a well-tolerated office procedure. The aim of our study was to verify compliance, side-effects and haemodynamic variations when a mini-hysteroscope is used. Methods: A prospective randomized trial on office hysteroscopy was performed by comparing the use of a traditional 5 mm hysteroscope (group A) and of a 3.3 mm mini-hysteroscope (group B). Two patient groups (A and B), each comprising 100 cases, were formed on the basis of a randomized computer-generated list. Results: A marked reduction in the mean (+/-SD) pelvic pain score during office hysteroscopy was seen in group B (2.3+/-2.1) as compared with group A (4.6+/-2.2) (P<0.0001, Mann-Whitney test). This result was also confirmed when using an alternative approach: four classes of pelvic pain at the visual analogue score (VAS). A significant reduction was observed in the incidence of moderate and severe pelvic pain in group B at the end of the examination (P=0.001) and 5-10 min later (P<0.05). Conclusions: The use of mini-hysteroscopes (3.3 mm with diagnostic sheath) lowers considerably the level of pelvic pain the patients feel: it is halved in comparison with traditional calibre hysteroscopes (2.3+/-2.1, on a 0-10 VAS). Furthermore the outpatient hysteroscopy failure rate is less than half (2%) with the mini-hysteroscope compared with the traditional 5 mm hysteroscope (5%). As for side-effects and haemodynamic parameters, no differences were observed except for an increase (P<0.05) in bradycardia in group B. The advantage of this technique is self-evident, if the patients' compliance is taken into account: in many cases the introduction or withdrawal of the vaginal speculum was reported as the greatest discomfort.