Intrauterine Device Insertion Pain Management

Applying a New Method for Pain Control in Intrauterine Device Insertion

The goal of this clinical trial is to learn if use of topical benzocaine prior to the injection of lidocaine is effective in decreasing pain experienced during IUD insertion in patients 18 or older. The main question it aims to answer is:

Does topical use of benzocaine prior to lidocaine injection during IUD insertion effectively decrease pain experienced?

Researchers will compare benzocaine/lidocaine to benzocaine/placebo, placebo/lidocaine, and placebo/placebo to see if use of benzocaine prior to lidocaine injection works more effectively to decrease pain experienced rather than lidocaine, benzocaine, or placebo use alone.

Participants will:

• Arrive to clinic for previously scheduled IUD insertion
• Be screened, approached by research staff, and consented to join the trial
• Complete a demographic questionnaire
• Be randomly and blindly assigned to one of four groups
• Placebo/Placebo
• Placebo/Lidocaine
• Benzocaine/Placebo
• Benzocaine/Lidocaine
• All groups will be given 600mg of ibuprofen prior to procedure
• Be asked to rate their pain on a visual scale of 1-10 during several distinct points of the procedure.
• Be sent an optional survey to their email after the procedure

Study Overview

• Status: Terminated
• Conditions: IUD Insertion; IUD Insertion Pain
• Intervention / Treatment: Other: Sham injection; Drug: Saline 0.9%; Drug: Lidocaine 2%; Drug: Benzocaine 20%

Detailed Description

The goal of the researchers is to determine if use of a topical benzocaine spray prior to lidocaine injection will cause a significant reduction in pain experienced by patients undergoing an IUD insertion. Participants will be screened, approached, and fully consented by research staff in the clinic prior to their IUD insertion. Demographics will be gathered from all participants through a questionnaire. All participants will be given 600mg of ibuprofen prior to the procedure, but will be randomized into one of 4 groups as to what interventions/placebos they will receive during their insertion. Interventions studied are benzocaine spray and lidocaine injection. Placebos will be saline spray and paracervical needle stick without injection. Participants will be asked to rate their pain on a visual scale of 1-10 at the following timepoints during the procedure:

• At the time of tenaculum placement
• At the time of uterine sounding
• At the time of IUD insertion and deployment
• Immediately after removal of instrumentation
• 15 minutes after the procedure Participants who provided an email will be sent an additional questionnaire to be responded to within 24 hours of the procedure. At the conclusion of the trial statistical analysis will be done to determine significance of pain reduction varying between the 4 groups.

• Study Type: Interventional
• Enrollment (Actual): 1
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Columbia, Missouri, United States, 65202
      • Missouri OB/GYN Associates-Smiley Lane

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18 years of age or older
• Undergoing IUD insertion

Exclusion Criteria:

• IUD insertion <6 weeks postpartum
• Age <18 years
• Allergy or history of adverse effect of lidocaine, benzocaine (and inactive ingredients: flavor, isobutane, propane, polyethylene glycol, sodium saccharin), or ibuprofen
• Not undergoing IUD insertion
• Undergoing IUD insertion under general anesthesia
• Usage of anti-inflammatory or as-needed anxiety medications (not daily use) in the 12 hours prior to IUD insertion

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo/Placebo; Participants in this arm will receive saline spray and a needle stick without injection to the cervix	Other: Sham injection; Sham injection to mimic Lidocaine paracervical block. Will use an injection needle and sham inject (no actual injection of fluid); Drug: Saline 0.9%; Saline spray to mimic use of benzocaine spray
Experimental: Placebo/Lidocaine; Participants in this arm will receive saline spray and injected lidocaine to the cervix	Drug: Saline 0.9%; Saline spray to mimic use of benzocaine spray; Drug: Lidocaine 2%; Lidocaine 2% injectable solution
Experimental: Benzocaine/Placebo; Participants in this arm will receive benzocaine spray and a needle stick without injection to the cervix	Other: Sham injection; Sham injection to mimic Lidocaine paracervical block. Will use an injection needle and sham inject (no actual injection of fluid); Drug: Benzocaine 20%; Benzocaine 20% topical spray
Experimental: Benzocaine/Lidocaine; Participants in this arm will receive benzocaine spray and lidocaine injection to the cervix	Drug: Lidocaine 2%; Lidocaine 2% injectable solution; Drug: Benzocaine 20%; Benzocaine 20% topical spray

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Pain Score During IUD Insertion Events as Quantified by Visual Analogue Scale	The Visual Analogue Scale (VAS) is a 0-10 pain intensity scale commonly used to assess pain intensity. Scores of 0 represent having no pain at all while scores of 10 represent worst pain possible; Therefore higher scores represent worse outcomes for pain management. VAS will be used to determine participant's levels of experienced pain at the 5 distinct events (tenaculum placement, uterine sounding, IUD insertion/deployment, immediately after instrumentation removal, 15 minutes post-procedure).	During IUD insertion procedure

Collaborators and Investigators

• Sponsor: University of Missouri-Columbia

Study record dates

Study Major Dates

• Study Start (Actual): June 23, 2025
• Primary Completion (Actual): April 15, 2026
• Study Completion (Actual): April 15, 2026

Study Registration Dates

• First Submitted: April 22, 2025
• First Submitted That Met QC Criteria: April 22, 2025
• First Posted (Actual): April 30, 2025

Study Record Updates

• Last Update Posted (Actual): April 21, 2026
• Last Update Submitted That Met QC Criteria: April 15, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: paracervical block; benzocaine; IUD; IUD insertion; IUD insertion pain; paracervical lidocaine
• Additional Relevant MeSH Terms: Inorganic Chemicals; Chlorine Compounds; Sodium Compounds; Chlorides; Hydrochloric Acid; salicylhydroxamic acid; Sodium Chloride
• Other Study ID Numbers: 2101465

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Study Arm, Age, Parity, and Pain-scoring at different intervals
• IPD Sharing Time Frame: IPD will be made available via link after conclusion of study (anticipated by 12/31/2026) and will remain available indefinitely on the MOspace institutional repository so long as that service remains active.
• IPD Sharing Access Criteria: IPD will be made available to all through the use of the MOspace institutional repository. Individual participant data will be available on a spreadsheet detailing study arm, age, parity, and pain-scoring at the different intervals. This will be accessible through a unique URL that will be provided at the conclusion of the study and upon upload to the MOspace repository.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No