Treatment of Chronic Pelvic Pain Due to Endometriosis by Transcutaneous Auricular Vagus Nerve Stimulation (Stim-Endom)

November 18, 2025 updated by: Hopital Foch

6-10% of women of childbearing age suffer from endometriosis, which is mainly manifested by dysmenorrhea, non-menstrual pelvic pain and dyspareunia. Several treatment strategies, including surgical ones, are proposed but they are sometimes insufficient because endometriosis-related pain is frequently accompanied by sensitization. Endometriosis surgery, when indicated, is therefore changeably effective, even though the lesions have been completely resected. Patients therefore consult Pain Units seeking for the effective treatment as the pain persist even after surgical management of endometriosis.

Vagus nerve stimulation is a non-invasive technique that includes an anti-inflammatory effect and a modulation of neurotransmitter production (adrenaline, norepinephrine; serotonin, acetylcholine). Yuan and Silberstein published a general review on the technique. Migraine and depression are one of the selected indications. In addition, Napadow et al. published favourable results in a short series of patients with chronic pelvic pain. The Investigators of this study have treated some patients with this technique with a result deemed satisfactory which leads to propose a randomized study to confirm this impression.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
72

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

15 years and older (Child, Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Women aged >= 15 years
  • With chronic pelvic pain and/ or dysmenorrhoea and/ or dyspareunia
  • Who has been cared for by a gynecologist in one of the institutions participating in the study
  • Diagnosed with endometriosis
  • Having signed an informed written consent
  • Affiliated to a health insurance scheme

Exclusion Criteria:

  • contraindication to the use of transcutaneous auricular vagus nerve stimulation (cardiac pathology, asthmatic patient)
  • pregnant or breastfeeding women
  • patient undergoing in vitro fertilization
  • associated pathology requiring long-term analgesic treatment
  • patient with atria trans vagal neurostimulation in the 12 months prior to inclusion
  • patient deprived of liberty or under guardianship

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Transcutaneous auricular vagus nerve stimulation

A 30-minute session twice a day during 3 months of transcutaneous auricular vagus nerve stimulation using the TENS Eco Plus.

Standard treatment will be continued by the patients of this arm.
Device: Transcutaneous Auricular Vagus Nerve Stimulation

Transcutaneous Auricular Vagus Nerve Stimulation has an eartip connected to an external stimulator. The device used in this study is the TENS Eco Plus commercialized by Schwa Medico and European Compliance (CE) marked.

The electrode is positioned in the cymba concha of the left ear.
No Intervention: Standard treatment
Patients of this arm will continue their standard treatment.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Change of symptoms related to the pelvic pain
Time Frame: 3 months after enrolment
Self assessement of change using Patient's Global Impression of Change (PGIC) scale in which patients rate the improvement of their symptoms related to their pelvic pain from "No change or it get worse" to "A great deal better, and a considerable improvement that has made all the difference" . A favorable result will be "Better, and a definite improvement that has made a real and worthwhile difference" or "A great deal better, and a considerable improvement that has made all the difference"
3 months after enrolment

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Efficacy on pain
Time Frame: Day 1 and 3 months after enrolment
Self assessement of pain using Endometriosis-associated pelvic pain scale on which patients rate their current pain intensity from 0 "No pain" to 10 "worst possible pain"
Day 1 and 3 months after enrolment
Efficacy on severity of patient's symptoms
Time Frame: Day 1 and 3 months after enrolment
Physician assessement of severity of patient's symptoms using Global Clinical Impressions-Severity scale on which physicians rate the severity of patient's symptoms from "not evaluated" to "Among the sickest patients"
Day 1 and 3 months after enrolment
Efficacy on quality of life
Time Frame: Day 1 and 3 months after enrolment
Self assessement of quality of life using Endometriosis Health Profile-5
Day 1 and 3 months after enrolment
Efficacy on quality of life
Time Frame: Day 1 and 3 months after enrolment
Self assessement of quality of life using EQ-5D scale
Day 1 and 3 months after enrolment
Efficacy on Anxiety
Time Frame: Day 1 and 3 months after enrolment
Self assessement of anxiety using the Hospital Anxiety and Depression scale
Day 1 and 3 months after enrolment
Efficacy on gynecological and pelvic pain symptoms
Time Frame: Day 1 and 3 months after enrolment
Self assessement of gynecological and pelvic pain symptoms using ENDOL-4D questionnaire
Day 1 and 3 months after enrolment
Efficacy on gynecological and pelvic pain symptoms
Time Frame: D1 and 3 months after enrolment
Self assessement of gynecological and pelvic pain symptoms using KESS questionnaire
D1 and 3 months after enrolment
General efficacy of the device Transcutaneous Electronic Neuro Stimulation TENS Eco Plus
Time Frame: 3 months after enrolment
Self assessement of satisfaction using a satisfaction questionnaire involving satisfaction, adherence to treatment sessions and ease of use of the device
3 months after enrolment
Collection of possible side effects
Time Frame: 3 months after Enrolement
collection of vagal malaise, nausea and vomiting
3 months after Enrolement

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Hopital Foch

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Study Chair: Marc FISCHLER, MD PhD, Hôpital Foch, Suresnes
  • Principal Investigator: Mireille MICHEL-CHERQUI, MD, Hôpital Foch, Suresnes

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
December 13, 2021

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 28, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 28, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 13, 2019

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 25, 2019

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 26, 2019

Study Record Updates

Last Update Posted (Estimated)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 21, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 18, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2019-0057

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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