The efficacy and safety of intrauterine lidocaine instillation during outpatient hysteroscopy: A systematic review and meta-analysis of randomized controlled trials.

AIM: This systematic review and meta-analysis aimed to evaluate the efficacy and safety of intrauterine lidocaine for pain control during outpatient hysteroscopy by synthesizing evidence from randomized controlled trials (RCTs).

METHODS

A comprehensive search of PubMed, Scopus, CENTRAL, and Web of Science was conducted for RCTs up to September 2025. The primary outcome was pain, with secondary outcomes including patient satisfaction, need for additional analgesia, and adverse events. Standardized mean differences (SMD) for pain scores and risk ratios (RR) for dichotomous outcomes were pooled using Stata 19 with 95% confidence intervals (CI).

RESULTS

Nine RCTs involving 1,045 patients were included. Compared to placebo, intrauterine lidocaine significantly reduced pain during hysteroscope insertion (SMD: -0.64, 95% CI [-0.89, -0.39]; p < 0.001) and at 10 min post-procedure (SMD: -1.07, 95% CI [-1.40, -0.74]; p < 0.001). However, no significant differences were found during uterine visualization (p = 0.07), endometrial biopsy (p = 0.12), or at 30 min post-procedure (p = 0.06). Lidocaine showed no difference compared to rectal NSAIDs. Despite mixed results on pain scores, lidocaine was associated with significantly higher patient satisfaction. It also showed a non-significant trend towards reducing the need for additional analgesia (RR: 0.53, 95% CI [0.26, 1.09]; p = 0.08) without increasing the overall risk of adverse events compared to the placebo (RR: 1.20, 95% CI [0.59, 2.46]; p = 0.61).

CONCLUSION

Intrauterine lidocaine appears safe and may reduce pain during hysteroscope insertion while improving patient satisfaction; however, its analgesic effect is transient and limited for pain related to uterine distension or biopsy, highlighting the need for further high-quality trials.