Needle-Free Intrauterine Anesthesia Technique Reduces Pain During IUD Insertion

Avoiding or undertreating procedural pain can reduce uptake and satisfaction with effective reproductive care. Researchers have now developed a simple intrauterine local anesthesia approach to make IUD insertion more tolerable. A new randomized clinical trial reports clinically meaningful reductions in pain and improved patient experience with this technique.

Karolinska Institutet (Stockholm, Sweden) evaluated intrauterine instillation of the local anesthetic mepivacaine delivered through a thin plastic catheter a few minutes before insertion. The technique targets the uterine cavity rather than cervical tissue and avoids needle injections. In usual practice, IUDs are placed without anesthesia or with a paracervical injection that itself can be painful.

The randomized clinical study enrolled 370 women aged 18 to 31 who had not previously given birth. Participants were assigned to receive either intrauterine mepivacaine or a saline placebo. Neither patients nor clinical staff knew which treatment was given.

Pain scores on a 0–100 scale averaged 43.8 with mepivacaine and 58.6 with placebo, a reduction of about 15 units. The share reporting the procedure as tolerable increased from 91.4% with placebo to 98.3% with mepivacaine. More than half of the treated group found insertion easier than expected, compared with about one third of controls. Most participants described the anesthetic administration itself as only mildly painful.

The trial was conducted across 11 gynecology clinics and youth health centers in Sweden. Outcomes were self-reported and the method was not compared directly with other analgesic strategies, which the investigators noted as limitations. The findings were published on September 17, 2026, in the JAMA. Some researchers reported lecture honoraria from intrauterine device makers, and those companies had no role in the study’s conduct or analysis.

“We can see that the method not only reduces pain, but also means that more people find the procedure acceptable,” said Helena Kopp Kallner, professor at the Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet, and senior consultant at the Women's Clinic at Danderyd Hospital.

“It is a simple method that does not require needles and is easy to use in everyday clinical practice,” said lead author Karin Elgemark, a doctoral student at the Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet.

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