Effectiveness of intrauterine anesthesia on pain management during IUD insertion: A meta-analysis of randomized...

To evaluate intrauterine anesthesia (IUA) compared with normal saline infusion for pain reduction during intrauterine device (IUD) placement.

Systematic review and meta-analysis of randomized controlled trials (RCTs) comparing IUA with saline in nulliparous and parous women undergoing IUD insertion. Eligible studies were RCTs reporting at least one pain related outcome; postpartum insertions were excluded. We searched PubMed, Embase, and Cochrane databases in November 2024. The primary outcome was pain during IUD insertion. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool, and heterogeneity using I². Analyses were performed in Review Manager (RevMan) version 7.12.0.

Six RCTs involving 651 women were included; 68% were nulliparous and 49.3% received IUA. Five studies with 427 women contributed to the analysis of pain during IUD insertion, which was significantly lower with IUA compared with placebo (SMD -0.47; 95% CI -0.90 to -0.03; p = 0.04; I² = 58%). In subgroup analysis, two studies including a total of 262 patients receiving lidocaine demonstrated a significant reduction in pain during IUD insertion (p = 0.0002), whereas two studies including 165 patients utilizing other anesthetic agents showed no significant effect (p = 0.27). Pain after insertion did not differ significantly between groups (p = 0.05). All studies had low risk of bias.

Intrauterine anesthesia reduced pain during IUD insertion compared with saline infusion; however, the effect of infusion itself on procedural discomfort remains uncertain.

Intrauterine anesthesia, particularly lidocaine, may be considered as a simple and low-risk strategy to reduce pain during IUD insertion, especially among nulliparous women who are more likely to experience procedural discomfort. Improving pain control during insertion may enhance patient comfort, satisfaction, and acceptability of long-acting reversible contraception. However, because all included studies compared anesthetic infusion with saline infusion rather than no infusion, further randomized studies are needed to clarify the true analgesic effect of intrauterine anesthesia.