Background Various medications have been investigated for their efficacy in pain reduction during intrauterine device (IUD) insertion, but there is currently no standard recommendation. This study aimed to investigate the efficacy of 10% lidocaine spray in reducing pain during copper-containing intrauterine device (Cu-IUD) insertion.

Methods This study was a randomised, double-blind, placebo-controlled trial. Reproductive-age women were randomised at a 1:1 ratio into 10% lidocaine spray or placebo spray group. A 10 cm visual analogue scale (VAS) was used to evaluate pain during several steps of the IUD insertion procedure, and after the procedure.

Results One hundred and twenty-four women were included and 62 women were randomised in each group. Baseline characteristics between groups were similar. The 10% lidocaine spray group demonstrated significantly lower median VAS immediately after IUD insertion than the placebo group (2.95 (IQR=1.00–5.63) vs 5.00 (IQR=3.35–7.00), respectively; p=0.002). Similarly, women receiving 10% lidocaine spray reported significantly lower median VAS than those receiving placebo during tenaculum use and uterine sounding. The maximum median VAS occurred immediately after Cu-IUD insertion. The proportion of women who reported VAS≥4 during uterine sounding and after IUD placement was significantly lower in the 10% lidocaine group than in the placebo group (p<0.05). Median change in VAS from baseline to IUD placement was significantly different between 10% lidocaine spray group and placebo group (1.85 (IQR=0.08–4.03) vs 3.6 (IQR=2.40–5.80), respectively; p=0.004).

Conclusion 10% lidocaine spray was found to be an effective local anaesthetic method for reducing pain during insertion of Cu-IUD.

Trial registration number Clinicaltrials.gov NCT03870711