TENS for Primary Dysmenorrhea (TENS-DYS)

Effect of Portable Transcutaneous Electrical Nerve Stimulation on Pain Intensity in Women With Primary Dysmenorrhea: A Randomized Controlled Pilot Study

Primary dysmenorrhea is a common gynecological condition characterized by recurrent menstrual pain in the absence of pelvic pathology. It affects a large proportion of women of reproductive age and may significantly interfere with daily activities, academic performance, and quality of life. Although pharmacological treatments such as nonsteroidal anti-inflammatory drugs are frequently used to manage menstrual pain, some women experience insufficient relief or prefer non-pharmacological treatment options.

Transcutaneous electrical nerve stimulation (TENS) is a non-invasive electrotherapy technique widely used in pain management. TENS is thought to reduce pain through mechanisms including modulation of nociceptive transmission at the spinal cord level and activation of endogenous analgesic pathways. Portable TENS devices may provide a convenient and accessible option for self-management of menstrual pain.

The aim of this randomized controlled pilot study was to evaluate the effectiveness of a portable TENS device in reducing pain intensity in women with primary dysmenorrhea. Participants diagnosed with primary dysmenorrhea were randomly assigned to either an intervention group receiving treatment with a portable TENS device or a control group receiving usual care.

The intervention consisted of the application of a portable TENS patch to the lower abdominal region during menstrual pain episodes. The device delivered alternating stimulation cycles combining high-frequency stimulation (85 Hz) and burst stimulation (2 Hz). Each treatment session lasted approximately 20 minutes and was applied during menstrual pain episodes.

Participants were followed for up to three menstrual cycles. Pain intensity was assessed using a visual analogue scale (VAS). Additional outcomes included quality of life assessed using the Short Form-12 Health Survey (SF-12), anxiety and depression measured with the Hospital Anxiety and Depression Scale (HADS), female sexual function evaluated with the Female Sexual Function questionnaire (FSM), and analgesic medication use recorded in a pain diary.

The results of this study aim to contribute to the evidence on non-pharmacological interventions for menstrual pain and to evaluate the potential role of portable TENS devices as a safe and accessible option for women with primary dysmenorrhea.

Study Overview

• Status: Completed
• Conditions: Primary Dysmenorrhea; Dysmenorrhea; Menstrual Pain
• Intervention / Treatment: Device: Transcutaneous Electrical Nerve Stimulation (TENS)

Detailed Description

Primary dysmenorrhea is a common gynecological condition characterized by recurrent menstrual pain in the absence of identifiable pelvic pathology. It affects a substantial proportion of women of reproductive age and is frequently associated with symptoms such as abdominal cramps, low back pain, nausea, fatigue, and headache. The condition may negatively affect daily functioning, academic performance, and quality of life. Despite its high prevalence, many women continue to experience inadequate pain control or adverse effects from pharmacological treatments.

Menstrual pain in primary dysmenorrhea is primarily associated with increased production of prostaglandins in the endometrium during menstruation. Elevated prostaglandin levels increase uterine contractility and vasoconstriction, which can result in uterine ischemia and activation of nociceptive pathways. These mechanisms contribute to the characteristic cramping pain experienced during menstruation.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used as first-line pharmacological treatment because they inhibit prostaglandin synthesis. However, some women experience insufficient pain relief, contraindications, or adverse effects associated with pharmacological therapies. For this reason, there is growing interest in non-pharmacological approaches to the management of primary dysmenorrhea.

Transcutaneous electrical nerve stimulation (TENS) is a non-invasive electrotherapy modality widely used for pain management in various clinical conditions. TENS delivers low-voltage electrical currents through electrodes placed on the skin, stimulating peripheral nerves. The analgesic effect of TENS is thought to be mediated by several physiological mechanisms, including activation of large-diameter afferent fibers that inhibit nociceptive transmission at the spinal cord level (gate control mechanism), as well as activation of descending inhibitory pathways and endogenous opioid release.

Several studies have suggested that TENS may reduce pain intensity in women with primary dysmenorrhea. In addition, portable TENS devices allow self-administration of therapy and may represent a convenient and accessible strategy for managing menstrual pain outside of clinical settings.

The aim of this randomized controlled pilot study was to evaluate the effectiveness of a portable transcutaneous electrical nerve stimulation device in reducing pain intensity in women with primary dysmenorrhea.

Participants diagnosed with primary dysmenorrhea were recruited and randomly allocated to one of two groups: an intervention group receiving portable TENS therapy or a control group receiving usual care. Randomization was performed using a simple allocation procedure to assign participants to either group.

Participants in the intervention group used a portable TENS device applied to the lower abdominal region during menstrual pain episodes. The device delivered alternating stimulation cycles combining high-frequency stimulation (85 Hz) and burst stimulation (2 Hz). This combination of stimulation parameters was selected to potentially activate both segmental analgesic mechanisms and endogenous opioid-mediated pathways.

Each treatment session lasted approximately 20 minutes and was applied during menstrual pain episodes. Participants were instructed on the correct placement and use of the device before beginning the study.

Participants in the control group continued their usual management strategies for menstrual pain, which typically consisted of analgesic medication taken as needed.

The study was conducted over two to three menstrual cycles. During this period, participants recorded their pain intensity and medication use. Pain intensity was assessed using a visual analogue scale (VAS), which is a widely used and validated tool for measuring subjective pain intensity.

Additional outcomes were assessed to explore the potential broader effects of the intervention. Quality of life was evaluated using the Short Form-12 Health Survey (SF-12). Anxiety and depression were assessed using the Hospital Anxiety and Depression Scale (HADS). Female sexual function was evaluated using a validated questionnaire. Analgesic medication use was also recorded during the study period.

Data collected during the study were analyzed to compare pain intensity and other outcomes between the intervention and control groups across menstrual cycles. The results of this study are intended to contribute to the evidence regarding the effectiveness of portable TENS devices as a non-pharmacological intervention for primary dysmenorrhea.

The findings may help inform future research and support the development of non-invasive strategies to improve pain management and quality of life in women experiencing menstrual pain.

• Study Type: Interventional
• Enrollment (Actual): 34
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Madrid, Spain
    • Universidad de Valencia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Women diagnosed with primary dysmenorrhea

History of recurrent menstrual pain without identifiable pelvic pathology

Regular menstrual cycles

Age between 18 and 45 years old

Pain intensity of at least 4 on a 10-cm Visual Analogue Scale (VAS)

Willingness to participate in the study and to comply with study procedures

Provision of written informed consent

Exclusion Criteria:

Secondary dysmenorrhea associated with identifiable pelvic pathology

Pregnancy

Irregular menstrual cycles

Use of hormonal contraceptives initiated or modified during the study period

Presence of gynecological or systemic conditions that could influence menstrual pain

Contraindications to transcutaneous electrical nerve stimulation (TENS), such as pacemaker implantation or skin lesions at the electrode placement site

Inability to understand study procedures or complete study questionnaires

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: TENS Intervention Group; Portable transcutaneous electrical nerve stimulation (TENS) device applied to the lower abdominal region during menstrual pain episodes. The device delivered alternating cycles of high-frequency stimulation (85 Hz) and burst stimulation (2 Hz). Each session lasted approximately 20 minutes, with intensity adjusted to a strong but comfortable sensory level.	Device: Transcutaneous Electrical Nerve Stimulation (TENS); Participants received treatment with a portable transcutaneous electrical nerve stimulation (TENS) device applied to the lower abdominal region during episodes of menstrual pain. The device delivered alternating stimulation cycles combining high-frequency stimulation (85 Hz) and burst stimulation (2 Hz). Each session lasted approximately 20 minutes, with stimulation intensity adjusted individually to a strong but comfortable sensory level. The intervention was self-administered during menstrual pain episodes across up to three consecutive menstrual cycles.
No Intervention: Usual care control group; Participants continued their usual care during menstrual pain episodes, including the use of analgesic medication if needed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain intensity measured using the Visual Analogue Scale (VAS)	Pain intensity associated with primary dysmenorrhea measured using a 10-cm Visual Analogue Scale (VAS), where 0 represents no pain and 10 represents the worst pain imaginable.	Measured at the end of each menstrual cycle (each cycle is approximately 28 days), up to 3 cycles

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Health-related quality of life measured using the Short Form-12 Health Survey (SF-12)	Health-related quality of life assessed using the Short Form-12 Health Survey (SF-12), which evaluates physical and mental health components. Higher scores indicate better perceived health status.	Measured at the end of each menstrual cycle (each cycle is approximately 28 days), up to 3 cycles
Anxiety and depression assessed using the Hospital Anxiety and Depression Scale (HADS)	Psychological symptoms assessed using the Hospital Anxiety and Depression Scale (HADS), a validated questionnaire composed of two subscales measuring anxiety and depressive symptoms. Higher scores indicate greater levels of anxiety or depression.	Measured at the end of each menstrual cycle (each cycle is approximately 28 days), up to 3 cycles
Female sexual function assessed using the Female Sexual Function questionnaire (FSM)	Female sexual function assessed using the Female Sexual Function questionnaire (FSM), a validated instrument evaluating domains such as desire, arousal, lubrication, orgasm, satisfaction, and pain during sexual activity.	Measured at the end of each menstrual cycle (each cycle is approximately 28 days), up to 3 cycles
Analgesic medication use recorded during menstrual pain episodes	Use of analgesic medication recorded in a pain diary during menstrual pain episodes to monitor the need for pharmacological pain management.	Measured at the end of each menstrual cycle (each cycle is approximately 28 days), up to 3 cycles

Collaborators and Investigators

• Sponsor: Centro Universitario La Salle
• Investigators: Principal Investigator: Jose Vicente León Hernández, PhD, CSEU La Salle, UAM (Madrid)

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2019
• Primary Completion (Actual): November 1, 2019
• Study Completion (Actual): December 20, 2019

Study Registration Dates

• First Submitted: March 7, 2026
• First Submitted That Met QC Criteria: April 8, 2026
• First Posted (Actual): April 13, 2026

Study Record Updates

• Last Update Posted (Actual): April 13, 2026
• Last Update Submitted That Met QC Criteria: April 8, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Women's Health; Pain Management; Primary Dysmenorrhea; Menstrual Pain; Transcutaneous Electrical Nerve Stimulation; Non-Pharmacological Treatment
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Nervous System Diseases; Pathologic Processes; Neurobehavioral Manifestations; Pelvic Pain; Perceptual Disorders; Menstruation Disturbances; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Agnosia; Dysmenorrhea; Therapeutics; Physical Therapy Modalities; Rehabilitation; Anesthesia and Analgesia; Electric Stimulation Therapy; Analgesia; Transcutaneous Electric Nerve Stimulation
• Other Study ID Numbers: CSEULS-PI-025/2019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data (IPD) will not be made publicly available because the dataset contains sensitive health-related information and there is no established data-sharing plan for this study. Aggregate results will be reported in scientific publications.

Study Data/Documents

1. Study Protocol

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No