Intrauterine Mepivacaine Cuts IUD Insertion Pain in RCT
Fear of pain remains a major deterrent for patients considering intrauterine contraception. Fortunately, intrauterine mepivacaine instillation offers an effective, needle-free solution to reduce procedural discomfort. A multicenter randomized clinical trial evaluated whether this simple technique improves patient comfort during intrauterine device (IUD) insertion in nulliparous individuals.
Trial Design and Protocol Overview
Researchers conducted this double-blind trial across 11 outpatient clinics in Sweden. They enrolled 370 nulliparous individuals between 18 and 31 years of age. Eligible patients planned to receive smaller-diameter IUDs, such as low-dose levonorgestrel or copper devices. However, clinicians excluded individuals with active pelvic infections, existing pregnancies, or local anesthetic allergies.
Clinicians randomly assigned participants to receive either mepivacaine or saline placebo. Specifically, providers instilled 10 mL of mepivacaine (20 mg/mL) or sodium chloride through a hydrosonography catheter. They completed this instillation two minutes before the IUD placement. Furthermore, investigators ensured rigorous blinding of participants, clinicians, and outcome assessors.
Intrauterine Mepivacaine Instillation: Efficacy and Outcomes
The primary outcome measured clinician-adjusted differences in insertion pain using a 100-mm visual analog scale. Notably, participants in the mepivacaine group experienced substantially less discomfort. The mean pain score was 43.8 mm with mepivacaine compared to 58.6 mm with placebo. Consequently, mepivacaine yielded a statistically significant mean reduction of 14.8 mm.
In addition, secondary analyses confirmed superior tolerability and patient satisfaction. Almost all patients in the mepivacaine group rated their pain as tolerable. Moreover, over half of the treated patients reported that the insertion was easier than anticipated. Participants also reported that the catheter instillation caused minimal baseline discomfort.
Clinical Implications for Practice
Routine IUD insertion often causes significant distress, particularly in nulliparous women. Traditional paracervical blocks reduce cervical pain effectively, but many patients dread the injection needle. In contrast, intrauterine instillation requires only a soft catheter and provides needle-free pain relief. Therefore, gynecologists can seamlessly incorporate this technique into regular outpatient settings.
Adopting this approach aligns with recent guidelines emphasizing proactive pain management for uterine procedures. By reducing procedural pain, clinicians can support patient autonomy and contraceptive uptake. Thus, mepivacaine instillation represents a practical, patient-centered advancement in reproductive healthcare.
Frequently Asked Questions
Q1: How does intrauterine mepivacaine compare to paracervical blocks?
Intrauterine instillation delivers anesthesia directly to the uterine cavity without needles. Paracervical blocks numb the cervix via injection, which can provoke procedural anxiety.
Q2: How long does the mepivacaine instillation take to take effect?
In clinical trials, clinicians placed the IUD two minutes after instilling mepivacaine. This rapid onset allows smooth integration into standard clinic appointments.
Q3: Is intrauterine instillation painful for the patient?
Most participants reported only mild discomfort during catheter placement. As a result, patients found the overall insertion experience significantly easier.
References
- Elgemark K et al. Intrauterine Mepivacaine Instillation vs Placebo for Pain During IUD Placement: A Randomized Clinical Trial. JAMA. 2026 Sep 17. doi: 10.1001/jama.2026.14217. PMID: 42752558.
- Envall N, Elgemark K, Kopp Kallner H. Mepivacaine instillation for pain reduction during intrauterine device placement in nulliparous women: a double-blinded randomized trial. Am J Obstet Gynecol. 2024;231(5):524.e1-524.e7.
- American College of Obstetricians and Gynecologists. Clinical Consensus No. 9: Pain Management for In-Office Uterine and Cervical Procedures. Obstet Gynecol. 2025;145(6):e120-e134.
