Effect of Cervical Lidocaine-prilocaine Cream on IUD Insertion Pain: A Randomized Controlled Trial

IUD can cause pain and discomfort in several ways: Use of the tenaculum to grasp the cervix and straighten the uterus for proper insertion; trans-cervical actions including measuring uterine depth, inserting the IUD insertion tube, and removing the tube; and placement of the device in the uterus.

To minimize the discomfort and the hazards of an IUD insertion, several measures have been proposed including NSAIDs, anxiolytics, and local anesthetics in the form of intracervical gel, cervical and para-cervical block, but there have not done enough studies about their effectiveness. According to the review published in the Cochrane, non-steroidal anti-inflammatory drugs and misoprostol are not effective on reducing an IUD insertion pain. Many trials have been done about effectiveness of lidocaine gel in reducing pain during IUD insertion and only one of those trials showed positive effect of 2% lidocaine gel, while others failed.

Lidocaine 2.5% and Prilocaine 2.5% Cream, is an emulsion in which the oil phase is a eutectic mixture of Lidocaine and Prilocaine cream in a ratio of 1:1 by weight. This eutectic mixture has a melting point below room temperature and therefore both local anesthetics exist as liquid oil rather than as crystals. Its absorption of from the genital mucosa is more rapid and onset time is shorter (5 to 10 minutes) than after application to intact skin. After a 5 to 10 minute application of Lidocaine-Prilocaine cream to female genital mucosa, the average duration of effective analgesia was 15 to 20 minutes.