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

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: Recruiting
• Conditions: Endometriosis
• Intervention / Treatment: Device: Transcutaneous Auricular Vagus Nerve Stimulation

• Study Type: Interventional
• Enrollment (Estimated): 72
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Mireille MICHEL-CHERQUI, MD; Phone Number: 0033 1 46 25 29 85; Email: drci.promotion@hopital-foch.com

Study Locations

• France
  • Île-de-France Region
    • Suresnes, Île-de-France Region, France, 92150
      • Recruiting
      • Hôpital Foch
      • Contact: Mireille Michel-cherqui, MD; Email: drci.promotion@hopital-foch.com

Participation Criteria

Eligibility Criteria

• 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

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
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

Outcome Measure	Measure Description	Time Frame
Change of symptoms related to the pelvic pain	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

Outcome Measure	Measure Description	Time Frame
Efficacy on pain	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	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	Self assessement of quality of life using Endometriosis Health Profile-5	Day 1 and 3 months after enrolment
Efficacy on quality of life	Self assessement of quality of life using EQ-5D scale	Day 1 and 3 months after enrolment
Efficacy on Anxiety	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	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	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	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	collection of vagal malaise, nausea and vomiting	3 months after Enrolement

Collaborators and Investigators

• Sponsor: Hopital Foch
• Investigators: Study Chair: Marc FISCHLER, MD PhD, Hopital Foch, Suresnes; Principal Investigator: Mireille MICHEL-CHERQUI, MD, Hopital Foch, Suresnes

Study record dates

Study Major Dates

• Study Start (Actual): December 13, 2021
• Primary Completion (Estimated): March 28, 2027
• Study Completion (Estimated): March 28, 2027

Study Registration Dates

• First Submitted: November 13, 2019
• First Submitted That Met QC Criteria: November 25, 2019
• First Posted (Actual): November 26, 2019

Study Record Updates

• Last Update Posted (Estimated): November 21, 2025
• Last Update Submitted That Met QC Criteria: November 18, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Transcutaneous Auricular Vagus Nerve Stimulation; Chronic pelvic pain
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Genital Diseases, Female; Endometriosis
• Other Study ID 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