Whether intrauterine instillation of 10 mL mepivacaine (20 mg/mL) 2 minutes before IUD placement reduces procedural pain compared to saline placebo in nulliparous individuals aged 18–31 years, across 11 Swedish outpatient clinics (May 2021–June 2024).
Mepivacaine reduced mean pain scores during IUD placement by 14.8 mm on a 100-mm VAS (43.8 mm vs 58.6 mm; 95% CI, 10.0–19.6; P < .001); tolerable pain was reported by 98.3% vs 91.4% in the placebo group (NNT = 15).
Study enrolled only nulliparous individuals aged 18–31 using smaller-diameter IUD tubes in Sweden, limiting generalizability to parous patients, older adults, or larger-diameter devices. The instillation required a hydrosonography catheter, adding a procedural step not standard in all clinics.
For nulliparous patients getting an IUD, instilling 10 mL of mepivacaine (20 mg/mL) into the uterine cavity 2 minutes before placement meaningfully reduces pain and improves tolerability — consider adding this step to routine IUD placement protocols.
