A randomized controlled trial of 2% lidocaine gel for IUD insertion
Awarded 2010
Large Research Grants
Rebecca Allen, MD, MPH
Women and Infants Hospital

Background: The intrauterine device is a long-acting, highly effective, reversible contraceptive that may be underutilized due to fear of pain during insertion. To date, in clinical trials, misoprostol, nonsteroidal anti-inflammatory drugs, paracervical block, and 1 mL of 2% lidocaine gel have been found to be ineffective. Methods: This is a randomized, placebo-controlled, double-blind trial evaluating the efficacy of cervical 2% lidocaine gel for IUD insertion pain. First-time IUD users were randomized to 2% lidocaine gel or placebo (Surgilube) gel. 3 mL of gel was applied to the anterior lip of the cervix and 3 mL was placed at the internal os with a catheter. After 3 minutes, IUD insertion was performed in the standard fashion with a tenaculum. The primary outcome was pain during insertion as measured on a 0 to 100 mm Visual Analog Scale. The study was powered to detect a 15 mm difference on the VAS between the 2 groups. Results: Of 145 women, 73 were randomized to placebo and 72 to 2% lidocaine gel. The groups were similar in age, race/ethnicity, BMI, parity, breastfeeding status, timing of IUD insertion, uterine position, anticipated pain, self-rated pain tolerance, and history of dysmenorrhea. Pain during speculum placement, as a baseline, was similar with a mean pain score (±SD) of 21.5 (±23.7) in the placebo arm and 23.5 (±23.8) in the 2% lidocaine gel arm. There was no difference in mean pain scores during tenaculum placement (41.6, ±31.5 and 37.5, ±26.2, p = 0.4)) in the placebo and lidocaine arm, respectively. There was no difference in mean pain scores in the placebo arm, 36.7 (±30) and the lidocaine arm, 35.2 (±27.7) with IUD insertion (p = 0.8). Conclusions: Six mL of cervical 2% lidocaine gel did not reduce pain during tenaculum placement or IUD insertion.