Could TENS machines be the future of menstrual pain relief?

Could TENS machines be the future of menstrual pain relief?

Could TENS machines be the future of menstrual pain relief?

The last few years have seen the start of a long overdue conversation about menstrual pain relief. Faithfully, tech companies have answered the call. But are TENS machines really the future of menstrual pain relief? We explore the history of TENS machines and their applications today.

Written by

Katie is a content creator and writer from Birmingham, UK. Passionate about menstrual, environmental and social justice & driven by the need for integrative education and intersectional advocacy.

What is a TENS machine?

TENS: Transcutaneous Electrical Nerve Stimulation. It may sound complicated, but it’s quite simple: a device produces electrical currents that stimulate the nerves in our body, the result is a pain therapy that doesn’t require medication. Electrodes, usually (no more than two) gel pads, are attached to the skin at the affected area.

These electrodes conduct electrical currents created by the TENS machine to our nerves, in the form of small electrical impulses. The impulses’ function is twofold, both suppressing pain signals sent to the brain via our nerves and stimulating the production of our natural pain killing chemicals, endorphins and enkephalins. These impulses can have varying frequency 

(the number of waves passing a fixed point per second), varying intensity from sensory (strong but comfortable) to motor (causing contractions in the muscles) and can be delivered in different combinations of frequency and intensity, based on the requisite function. Generally, if a high frequency is used, a low intensity is used too, and vice-versa.

What have they been used for historically?

You might be surprised to find out that the concept of electrical stimulation for pain relief is recorded as far back as Ancient Roman times, when court physician to Emperor Claudius, Scribonius Largus, stood on an electrical fish and noticed that his pain disappeared.

1600 years later a useable ‘electrostatic’ device was created, aiming to generate electricity from friction. Notably, Benjamin Franklin advocated potential medical applications, such as relief from headaches and other general ailments. Despite significant scientific interest in these ‘electrostatic’ devices from the 16th to 18th Century, there is little evidence that they were safe, let alone effective.

It wasn’t until the 19th Century that electrical devices became popular, even fashionable, for pain relief. They often made bold claims about their application. The ‘electreat’ was semi-portable, and used rollers to conduct electrical currents, claiming to cure anything from hay fever to deafness


Luckily, in the 20th Century these experimental machines fell from medical grace, there was no empirical evidence about their efficacy, safety or application.

The mid 1900s saw somewhat of a revival for electrotherapy – during a time that science was beginning to understand electricity and medicine on a far deeper level.

In 1974, C. Norman Shealy developed the first ever wearable TENS machine, but it wasn’t intended for pain relief. Rather, it was used to test the tolerance of people suffering chronic pain before fitting a pain-relieving implant into their spinal cord. Many patients never turned up for their implant, finding an impressive amount of pain relief from the TENS machine itself.

Since then, TENS have been used for a variety of conditions, and research into their efficacy continues today.

So, can they help people suffering from menstrual pain?

Menstrual pain – or dysmenorrhea – is unavoidable for many of us, and ibuprofen and paracetamol rarely cut it when it comes to finding a ‘moment’s relief’.

TENS machines were first demonstrated to be an effective treatment for dysmenorrhea in 2002 and since then trials have continually shown TENS to be safe and effective in providing pain reduction. The quick set-up allows them to relieve pain almost instantaneously; the ability to use the treatment as long or as little as needed according to our needs has far reaching implications for modern menstrual pain relief.

Specific settings and clinical considerations are still widely debated, but as people find out for themselves how much potential this treatment has, tech companies are funding more and more research, and competition between companies only serves to fuel the fires of development.

The advantages of a non-invasive treatment like this speak for themselves.

The need to manage medications and side effects is removed, as is the need for surgical intervention in milder cases. The machines themselves are inexpensive, and only need to be purchased once. The portable nature of modern devices means they can be used both at home and out and about, with little hassle.

Nothing is without limitations. For TENS machines, it’s the fact that they are not suitable for people with pacemakers, epilepsy, or certain heart conditions. Hugely disappointing for the many people included who experience dysmenorrhea but potentially something that could change in the future.

All in all, thanks to their affordability, these machines are revolutionary for people suffering painful periods all over the world.

Their application to menstrual pain is still relatively new, with huge development and research potential – if they are this effective already, imagine where they could take us.


“The use of transcutaneous neural stimulation and isokinetic testing in arthroscopic knee surgery” – This article includes the early history of TENS machines.

“Effectiveness of Transcutaneous Electrical Nerve Stimulation for Treatment of Hyperalgesia and Pain” – This article includes a very accessible scientific explanation of how TENS machines work.

“Transcutaneous Electrical Nerve Stimulation (TENS) for Primary Dysmenorrhea: An Overview” – This article talks about the earliest use of TENS for dysmenorrhea, and the progression of scientific understanding of TENS for this application.

This is a very charming image of the ‘instruction manual’ for an early TENS machines – the Electreat.

This is an abstract from “Gynaecology of middle-aged women–menstrual and reproductive histories” and gives an average amount of time that people will bleed for in their lifetime.

Pain: The experience

Pain: The experience

Pain: The experience

How can we measure our pain, and why does it matter?

Written by

Katie is a content creator and writer from Birmingham, UK. Passionate about menstrual, environmental and social justice & driven by the need for integrative education and intersectional advocacy.

No, it’s not the next life-altering, breath-taking, exhilarating ride brought to you by your favourite theme park… but it is life-altering. Millions of people suffering with menstrual health conditions experience it everyday. And similarly to a rollercoaster, you don’t know when it will end, how many twists and turns it will have along the way, or how it will affect you when you’re there and it’s really happening. In other words, you are not in control. Unlike a rollercoaster, you can’t choose not to board this ride, it just sweeps you along, admission free.

There’s much more to this. Pain is something we have all experienced throughout our lives, whether it be from stepping on a lego brick at 6am on your way to that first cup of coffee, or whether it is something more sinister and long-lasting, leaving a stamp on your mind, body and soul. Whichever way we experience pain, we experience it alone: with no direct comparisons, no get out of jail free card, and when it comes to menstrual pain, and often when it comes to menstrual pain, no effective pain management solutions.

Pain being so subjective presents a huge challenge when it comes to communicating our experiences, obtaining diagnoses and ultimately getting the help we need. After speaking with a GP and hearing about the huge variances in not only pain level, but how everybody has a different tolerance for the pain levels they are experiencing, we were left a little confused… of course this is the case, anecdotally we all know this to be true – still, this brought us no closer to understanding how we can objectively measure pain in order to gain a deeper understanding of menstrual health conditions.

The importance of truly understanding the pain people experience in response to different conditions stems from the need to create solutions. Without a proper understanding of the pain levels we are experiencing, we cannot measure the changes in pain levels resulting from solutions and interventions at a medical level. Nor can we understand how pain derived from a specific condition – such as endometriosis – affects the patient group as a whole, over time, during the span of our cycles in terms of physical pain.

So how do we quantify our pain?
These are the two main techniques used in the medical space:

The visual analogue scale (VAS)

How does it work?
Quite simply, the visual analogue scale is a unidimensional scale, used to indicate pain levels. Most commonly, the scale sits on a horizontal line, with the scale starting at ‘no pain’ on the left, moving to the right with ‘pain as bad as it could be’. The patient carries out the assessment themselves, simply pointing to or marking where on the scale they feel they are. The principle can be presented in a number of ways, but remains the same throughout. In paediatrics, the scale often relies on pictures of faces from happy (no pain) to really sad (the most pain). 

Clearly the simplicity and adaptability of this scale means that it can be applied in a wide range of settings and is accessible to most of us, from children, to professionals. After taking an initial measurement of pain level, ongoing monitoring of pain can be measured relative to the previous reading, so it is possible to build a picture of an individual’s pain ‘journey’ over a period of time, for instance a stay in hospital. It’s easy to use, accessible to nearly everyone, and can build a picture of improvements/deterioration in the patient’s condition – and that’s why it is so commonplace in medical care.

While this is great for understanding the subjective pain levels of an individual, we cannot build a picture of particular patient populations’ experiences using this scale. ‘Low level pain’ for one individual could be near the limit for another, and vice versa… this is not an objective measurement. Moreover, the complexity of pain including types (such as dull aches or sharp pains) is not captured on this scale.

The numeric rating scale (NRS)

How it works
The numeric rating scale applies the same principles of the visual analogue scale, but this time (you guessed it) with numbers. The scale usually runs on a horizontal line from left (0) to right (10), 0 being the least pain, 10 being the most.

The NRS can be administered verbally, making it perfect for tele-health consultations and patients with limited mobility. Similarly, since the scale relies on numbers rather than words, the scale can be used to communicate pain levels no matter the nationality of the patient. The scale has been found to be highly reliable across literate and illiterate patients alike. 

Along with the same cons that apply to the VAS, the numerical rating scale is also limited by its linear nature not allowing for qualitative descriptions of the complexity and idiosyncrasies of the pain experienced, perhaps to a greater extent than the VAS since written descriptions are not included in this scale. 

To sum up

They are simple. They are effective within the bounds of one patient’s experience. They are often used interchangeably, with VAS scores being converted into numerical ratings for clinical use. But is there a better way, one which accounts for our unique perspective on our own pain, or is this the best we can do? The medical profession has been using these scales for over a hundred years, and there is a reason for this – the ability to quantify pain in a simple number is eminently useful.

The future of pain measurement

Undoubtedly there is room for improvement. Regarding menstrual health, being able to articulate our pain effectively is critical in obtaining diagnoses and being ‘taken seriously’ by the medical professionals we rely on. There is a reason it takes an average of 7.5 years to get diagnosed with endometriosis. A lack of research into the nuances of (e.g. endometriosis) symptoms resulting in medical professionals relying on an oversimplified diagnostic pathway means that diagnoses often take years, or are completely missed, in some cases this is paired with stigma around ‘normal’ levels of menstrual pain meaning symptoms are not considered problematic. The reverse of this is contributive to the same problems: the lack of education around menstrual health from a patient perspective materialises in patients not being able to effectively communicate their symptoms (worsened by the cyclical nature of menstrual conditions), or even not identifying when symptoms are problematic and outside typical bounds of cramping pain. Clearly, when it comes to speeding up diagnoses for people living with dysmenorrhea, nuance and precise descriptions of the complexity of pain are essential – quantitative scales are not going to cut it.

Qualitative scales do exist, with several in use, the most common of which is an adaptation of the VAS. The VASQ asks “How is your pain today?” and the answer can define it as a ‘good pain day’, a ‘bad pain day’ and anything in between. However, for medical use these are often converted into quantitative figures, and once again the complexity of how we experience is oversimplified. Add a pinch of stigma, and a dollop of shame and guilt, and qualitative answers being converted to quantitative figures potentially underrepresents pain levels. Evidently, its subjective nature presents no simple answer to measuring complex pain; it is something that needs to be developed with menstrual health in mind

We need data, and lots of it. If we are limited to measuring pain on a quantitative, objective scale, the more information we have the better. Patterns relating to varying prolonged pain and hormonal cycles can be identified across patient groups and begin to paint a picture of how a condition such as endometriosis materialises pain, at which stages and how this impacts on daily living. 

“Researchers from MIT and elsewhere have developed a system that measures a patient’s pain level by analyzing brain activity from a portable neuroimaging device. The system could help doctors diagnose and treat pain in unconscious and non-communicative patients, which could reduce the risk of chronic pain that can occur after surgery.” Once this tech is developed and affordable, there is huge potential for gaining objective data about pain, and how we experience it, without our ‘communication styles’ affecting the way we describe our pain. But this is a long way off.

In the meantime, dig into the psychology – not only might we experience the same level of pain differently to someone else, we might experience the same level of pain differently ourselves, from one day to the next, particularly with hormonal cycles affecting sensitivity and mood.

It’s time to develop a closer relationship between physical health and psychological influences; emotional experiences are also an essential part of this puzzle. An integrative approach would open the doors to much deeper research, improving our understanding of pain amongst specific patient groups and opening the doors to developing effective pain management solutions. 

Kaleidas community, let’s get to work.