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Paracervical Block for Intrauterine Device Placement Among Nulliparous Women: A Randomized Controlled Trial
Sheila K Mody1, John Paul Farala, Berenice Jimenez
1Division of Family Planning, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, and Southern California Permanente Medical Group, San Diego, California.
Objective:
To investigate whether a 20-mL buffered 1% lidocaine paracervical block decreases pain during intrauterine device (IUD) placement.
Methods:
In a randomized, single-blind, placebo-controlled trial, women were assigned to receive either a 20-mL buffered 1% lidocaine paracervical block or no block before IUD placement. The primary outcome was pain with IUD placement measured on a 100-mm visual analog scale. Our sample size had 80% power (α=0.05) to detect a 20-mm difference in visual analog scale scores with a SD of 28 mm. Secondary outcomes included pain with speculum placement, paracervical block administration, tenaculum placement, 5 minutes postprocedure, and overall pain perception.
Results:
From October 7, 2014, through October 26, 2017, 64 women were enrolled and analyzed (33 in the paracervical block arm, 31 in the no-block arm). There were no differences in baseline demographics between the groups. 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). Pain was significantly less in the intervention group for uterine sounding (30 mm vs 47 mm, P=.005), 5 minutes after placement (12 mm vs 27 mm, P=.005), and overall pain perception (30 mm vs 51 mm, P=.015). Participants who received the paracervical block experienced more pain with block administration compared with placebo (30 mm vs 8 mm, P=.003). There was no perceived pain difference for speculum insertion (10 mm vs 6 mm, P=.447) or tenaculum placement (15 mm vs 10 mm, P=.268).
Conclusion:
A 20-mL buffered 1% lidocaine paracervical block decreases pain with IUD placement (primary outcome), uterine sounding (secondary outcome), and 5 minutes after placement (secondary outcome). Although paracervical block administration can be painful, perception of pain for overall IUD placement procedure is lower compared with no block.
Clinical Trial Registration:
ClinicalTrials.gov, NCT02219308.
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