Study of Pain Control With Hormonal IUS Insertion

Intrauterine systems (IUS) are among the most effective forms of reversible contraception. Numerous studies demonstrate their safety and efficacy. Despite this, uptake of IUSs among U.S. young women aged 14 to 22 years has been low. Increasing the use of this effective, long acting contraception among young women is an important public health goal, as it could help to reduce the high rates of unintended pregnancies in this population.

A major barrier to young women's utilization of IUSs is fear of pain during insertion. Unfortunately, studies evaluating methods of pain control during IUS insertion have focused on adult women, leaving the question unanswered as to the best pain management method for young women. Compared to adult women, young women have less experience with pelvic exams and may therefore derive greater benefit from pain control measures during gynecologic procedures, such as IUS insertions. Young women and their providers are seeking effective pain control options; yet, there is a lack of high quality, comparative effectiveness research to guide decision making. This proposal seeks to fill this important gap.

With the introduction of the Skyla IUS (Bayer Healthcare Pharmaceuticals, Inc.) to the U.S. market in January 2013, a new approach to pain management became possible. Skyla is smaller than existing IUSs and may therefore cause less pain during insertion. The pain response triggered during Skyla insertion may be better controlled by existing pain control options. This is the underlying premise of this study.

In addition to the size of an IUS, theoretical and empirical data suggest that paracervical blocks have the greatest promise for pain control during IUS insertion compared to other pain control options. Paracervical infiltration of a local anesthetic into the cervix interrupts the visceral sensory fibers of the lower uterus, cervix, and upper vagina. Data from several clinical trials indicate that paracervical blocks provide clinically significant control of pain during multiple types of gynecologic procedures. One recently published study evaluated the effectiveness of paracervical blocks during IUS insertion and found a marginally significant reduction in pain, but the study was underpowered and focused on adult women. The value of a paracervical block in young women receiving an IUS remains unclear.

The investigator propose to conduct a randomized, controlled single-blind trial comparing pain with Skyla IUS insertion among young women aged 14 to 22 years randomized to receive a paracervical block versus a sham cervical block. This study will provide important information for counseling young women about pain management during IUS insertion.

Inclusion criteria

• Nulliparous (i.e., no pregnancy > 24 weeks)
• Not currently pregnant
• Not pregnant in the past 6 weeks
• Willing to be randomized to a paracervical nerve block or sham paracervical block group
• Interested in using an intrauterine system (IUS)
• Able to read and provide written informed consent in English

Exclusion criteria

• An allergy, hypersensitivity, or absolute medical contra-indication to using lidocaine, other amino-amide local anesthetics, or to non-steroidal anti-inflammatory agents, such as ibuprofen
• A history of epilepsy or peptic ulcer disease
• Moderate to severe asthma that precludes non-steroidal anti-inflammatory drug (NSAID) use
• Hepatic or renal failure
• Moderate to severe cardiac disease
• Previous use of an IUS or a history of a prior failed IUS insertion
• Use of a narcotic or benzodiazepine in the past 24 hours
• Positive pregnancy test or reasonable risk of pregnancy
• Current cervicitis
• Intrauterine infection in the past 90 days
• Meet Centers for Disease Control Medical Eligibility Criteria (MEC) category 3 or 4 classification for IUS use
• Currently breastfeeding