Trial Outcomes & Findings for Use of TENS Unit in the Management of Endometriosis Pain (NCT NCT05348005)

Last Updated: 2026-08-04

Results Overview

Daily pain during endometriosis flares were recorded using a Visual Analog Scale (VAS), a horizontal line measuring pain from 0 (no pain) to 100 (worst pain). Per subject, an average pain score was calculated for the baseline period (no TENS use) and treatment period (TENS use). Change (treatment minus baseline) was estimated within the context of a repeated measures model; change in the positive direction represents worse outcome, change in the negative direction represents improvement.

Recruitment status

COMPLETED

Study phase

Target enrollment

40 participants

Primary outcome timeframe

Baseline period (months 1-3) and treatment period (months 4-6)

Results posted on

2026-08-04

Participant Flow

Participant milestones

Participant milestones
Measure	Study Cohort for TENS Subjects will be observed for 3 months (no intervention) during which time they will track endometriosis flares, followed by a 3-month intervention (TENS unit use) during endometriosis flares with diary tracking.
Overall Study STARTED	40
Overall Study COMPLETED	27
Overall Study NOT COMPLETED	13

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Use of TENS Unit in the Management of Endometriosis Pain

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Study Cohort n=40 Participants All subjects enrolled in the study start with 3 months of no TENS use and diary tracking
Age, Continuous	28.6 years STANDARD_DEVIATION 6.6 • n=20 Participants
Sex: Female, Male Female	40 Participants n=20 Participants
Sex: Female, Male Male	0 Participants n=20 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	4 Participants n=20 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	36 Participants n=20 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=20 Participants
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=20 Participants
Race (NIH/OMB) Asian	1 Participants n=20 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=20 Participants
Race (NIH/OMB) Black or African American	3 Participants n=20 Participants
Race (NIH/OMB) White	34 Participants n=20 Participants
Race (NIH/OMB) More than one race	0 Participants n=20 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=20 Participants

PRIMARY outcome

Timeframe: Baseline period (months 1-3) and treatment period (months 4-6)

Population: 38 subjects recorded VAS during the baseline period (months 1-3); 26 subjects recorded VAS during the treatment period (months 4-6). All average daily VAS scores (64 total observations across baseline period and treatment period) were included in the estimation of change.

Outcome measures

Outcome measures
Measure	Study Cohort for TENS n=38 Participants Subjects will be observed for 3 months (no intervention) during which time they will track endometriosis flares, followed by a 3-month intervention (TENS unit use) during endometriosis flares with diary tracking.
Change in Average Daily VAS Pain Score	-2.29 change in score on a scale Interval -8.31 to 3.73

SECONDARY outcome

Timeframe: Baseline and end of study (6 months)

Population: All subjects completed the baseline EHP30 questionnaire; 27 completed the end of study EHP30. All questionnaire data (67 total observations across baseline and end of study) were included in the estimation of change.

Change in quality of life from baseline to end of study using the Endometriosis Health Profile (EHP30) questionnaire. Scores range from 0 (best health status) to 100 (worst health status). Change (end of study minus baseline) was estimated within the context of a repeated measures model; change in the positive direction represents worse outcome, change in the negative direction represents improvement.

Outcome measures

Outcome measures
Measure	Study Cohort for TENS n=40 Participants Subjects will be observed for 3 months (no intervention) during which time they will track endometriosis flares, followed by a 3-month intervention (TENS unit use) during endometriosis flares with diary tracking.
Change in Quality of Life Score From Baseline to End of Study Using the EHP30 Questionnaire	-16.57 change in score on a scale Interval -22.38 to -10.77

SECONDARY outcome

Timeframe: Baseline and end of study (6 months)

Population: FSFI was completed by subjects with a current partner. 27 subjects completed the baseline FSFI questionnaire; 15 completed the end of study FSFI. All questionnaire data (42 total observations across baseline and end of study) were included in the estimation of change.

Change in FSFI validated survey scores from baseline to end of study among participants who are currently partnered. FSFI total score ranges from 2.0 (poor) to 36.0 (best). Change (end of study minus baseline) was estimated within the context of a repeated measures model; change in the positive direction represents improvement, change in the negative direction represents worse outcome.

Outcome measures

Outcome measures
Measure	Study Cohort for TENS n=27 Participants Subjects will be observed for 3 months (no intervention) during which time they will track endometriosis flares, followed by a 3-month intervention (TENS unit use) during endometriosis flares with diary tracking.
Change in Female Sexual Function Index (FSFI) Total Score From Baseline to End of Study	3.86 change in score on a scale Interval -0.61 to 8.33

Adverse Events

Study Cohort for TENS

Serious events: 0 serious events

Other events: 7 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Study Cohort for TENS n=40 participants at risk Subjects will be observed for 3 months (no intervention) during which time they will track endometriosis flares, followed by a 3-month intervention (TENS unit use) during endometriosis flares with diary tracking.
Skin and subcutaneous tissue disorders Skin irritation from use of TENS unit	10.0% 4/40 • Number of events 6 • 3-month TENS intervention period During the 3-month intervention period, diaries were recorded during endometriosis flares only and prompted the subject to report any side effects from using the TENS unit. Therefore, adverse event reporting is restricted to these self-reported diaries during TENS unit use.
General disorders Increased pain during/after TENS unit use	7.5% 3/40 • Number of events 5 • 3-month TENS intervention period During the 3-month intervention period, diaries were recorded during endometriosis flares only and prompted the subject to report any side effects from using the TENS unit. Therefore, adverse event reporting is restricted to these self-reported diaries during TENS unit use.

Additional Information

Kristin Riley, M.D.

The Pennsylvania State University

Phone: 717-531-0003

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place