Anaesthetic injections for pain with intrauterine device insertion
Evidence Summaries
A Cochrane review 1 included 33 studies with a total of 5,710 subjects. 400 mg of ibuprofen vs placebo at least 45 minutes prior to IUD insertion did not significantly reduce pain in 1 trial (mean difference in VAS -0.20, 95% CI -0.39to -0.01, n=2018). In another trial (n=55), ibuprofen 600 mg taken before IUD insertion did not show evidence of an effect on pain four to six hours after IUD insertion. Misoprostol for cervical ripening did not reduce pain with IUD insertion in nulliparous women. In one trial, naproxen as adjunctive treatment to paracervical block taken prior to IUD insertion was ineffective in reducing pain compared with placebo in the first two hours after IUD insertion in mostly nulliparous women. For lidocaine, meta-analysis showed topical 2% gel had no effect on pain at tenaculum placement (2 trials) or on pain during IUD insertion (3 trials).
A multisite, single-blind, sham-controlled randomized trial 2 in adolescents and young women (n=95) assessed the effect of a 10 mL 1% lidocaine paracervical nerve block on pain during intrauterine device (13.5-mg levonorgestrel IUD) insertion compared with a sham block. The median visual analog scale score after IUD insertion was 30.0 (95% CI 20.0 to 58.0) in the lidocaine block group and 71.5 (95% CI 66.0 to 82.0) in the sham block (P<.001).
In another randomized, single-blind, placebo-controlled trial 3 , women (n=64) were assigned to receive either a 20-mL buffered 1% lidocaine paracervical block or no block before IUD placement. Women who received the paracervical block reported less pain with IUD placement compared with women who received no block (median visual analog scale score of 33 mm vs 54 mm, P=.002).
In a randomized double-blind controlled trial 4 302 nulligravidas were block-randomized 3.6 mL 2%-lidocaine intracervical block, sham injection, or no intervention prior to 52-mg LNG-IUD insertion. Participants' pain was measured with a 10-cm visual analogue scale (VAS) and a 5-point Faces Pain Scale. The mean pain score reported was lower in the lidocaine group than in the other groups: intracervical block 4.3 (95% CI 3.8 to 4.9) vs sham 6.6 (95% CI 6.2 to 7.0), and intracervical block 4.3 (95% CI 3.8 to 4.9) vs no intervention 5.8 (95% CI 5.3 to 6.4).
An RCT 5 included 100 women. Women randomized to lidocaine intracervical block (6 mL 2%-lidocaine 5 minutes prior) presented lower mean pain score (VAS) at LNG-IUD insertion, when compared to women who received 550 naproxen 30 minutes prior (5.4 vs. 7.3, respectively; p < 0.001).
A meta-analysis 6 included 11 RCTs (n=1458) reporting paracervical lidocaine block or uterine mucosa lidocaine application before IUD insertion. Paracervical lidocaine block significantly reduced pain, mean difference -1.66, 95% CI -3.74 to 0.41, 4 trials, n=310). In 2 trials (n=212) topical 5% lidocaine + prilocaine cream (EMLA) reduced pain during insertion compared with placebo (mean difference -3.50, 95% CI -4.27 to -2.73 and -1.92, 95% CI -2.06 to 0.01 in VAS). Lidocaine gel or cream did not reduce pain in 4 trials, although there was a trend towards lower pain compared with placebo.
A systematic review and network meta-analysis 7 included 38 RCTs (n=6314). Compared with placebo, at IUD insertion lidocaine-prilocaine cream (genital mucosal application) and paracervical lidocaine significantly reduced pain (mean difference -2.76, 95% CI -4.61 to -0.91 and -1.13, 95% CI -2.42 to 0.16, respectively). Lidocaine gel (genital mucosal application) only showed a trend towards reduced pain (mean difference -0.95, 95% CI -2.12 to 0.22) compared with placebo.