Pain in diagnostic hysteroscopy: a multivariate analysis after a randomized, controlled trial.

Objective: To study which variables are able to influence women's experience of pain during diagnostic hysteroscopy.

Design: Multivariate analysis (phase II) after a randomized, controlled trial (phase I).

Setting: Endoscopic gynecologic center.

Patient(s): In phase I, 392 patients were analyzed. Group A: 197 women with carbon dioxide (CO2); group B: 195 women with normal saline. In phase II, 392 patients were assigned to two different groups according to their pain experience as measured by a visual analogue scale (VAS): group VAS>3 (170 patients); group VAS≤3 (222 patients).

Intervention(s): Free-anesthesia diagnostic hysteroscopy performed using CO2 or normal saline as distension media.

Main Outcome Measure(s): Procedure time, VAS score, image quality, and side effects during and after diagnostic hysteroscopy.

Result(s): In phase I the median pain score in group A was 2, whereas in group B it was 3. In phase II the duration of the procedure, nulliparity, and the use of normal saline were significantly correlated with VAS>3. A higher presence of cervical synechiae was observed in the group VAS>3. The multivariate analysis revealed an inverse correlation between parity and a VAS>3, whereas the use of normal saline, the presence of synechiae in the cervical canal, and the duration of the hysteroscopy were all directly correlated to a VAS score>3.

Conclusion(s): Pain in hysteroscopy is significantly related to the presence of cervical synechiae, to the duration of the procedure, and to the use of normal saline; conversely, parity seems to have a protective role.

Clinical Trial Registration Number: NCT01873391.