Comfort Measures in Labor: TENS
The first time I heard of a TENS machine was from my father. He has struggled with chronic back pain for many years that eventually became debilitating and requiring surgery. However, for several years before his surgery, he treated his back pain with a TENS machine.
How nerve impulses work
To understand how a TENS unit works, you must understand a little bit about how nerves work in your body.
Nerve fibers can be classified into three categories: A (largest), B, & C (smallest). Class A fibers can be further broken down into A-alpha (largest), A-beta, A-gamma, and A-delta (smallest).
Sensations such as touch and pressure are transmitted to the spinal cord through nerve fibers larger than A-delta. The smaller A-delta and C fibers are the pain sensors of the body. A-delta fibers carry signals much faster than C fibers and are responsible for sharp pain. C fibers transmit the slow, burning type pain.
Gate control is a theory involving how the brain senses pain. Scientists theorize that before a pain signal reaches the brain, they pass through “nerve gates” in the spinal cord to filter out some of the signals.
The theory says that by sending multiple types of stimulation, the nerve gates get “overwhelmed” and reduce the amount of signals getting through. It also hints that our brain has learned to control pain using this technique.
For example, if you hit your “funny bone,” you typically grab your elbow and start rubbing it or extend and bend your arm several times. This theory claims that our innate response is our way of sending additional signals to the “nerve gates” to reduce the amount of pain signals getting through to our brain. It is believed this is why massage, heat and cold, acupressure, acupuncture, and TENS therapy seems to help people tolerate pain.
What is TENS?
TENS stands for Transcutaneous electrical nerve stimulation. Essentially, it is a machine that sends a therapeutic electrical pulse to your muscle through pads placed on your skin.
This article stated that by using TENS, “the selective stimulation of the large diameter nerve fibers carrying non-pain sensory stimuli from a specific region nullifies or reduces the effect of pain signals from the region.”
The TENS machine often has different strength settings depending on how you want to use the machine. The more common setting is the higher pulse rate of 90-130 Hz. This setting utilizes the affects of the gate control theory. The lower setting of a pulse rate between 2-5 Hz can stimulate endorphin production, the body’s natural pain reliever.
It is best to use the machine for 15-20 mins at a time. You can use them several times a day but it is best to take a break from the stimulation every so often.
You should not used a TENS unit if you have a pacemaker or some other type of implanted electronic device, heart disease, epilepsy, or in or near water. If you are not in labor, you should check with your physician or midwife before using the device. For additional information, you may want to check out this article.
Does it work?
There are mixed responses to TENS therapy. Some people swear that it helps them avoid medicated pain relief, others say they felt no difference, and some found it an annoyance.
I have had TENS therapy while seeing a chiropractor. I did feel that it helped me relax but I am not sure how receptive I would be toward it in labor.
A TENS machine can be quite pricy. I suggest you try a TENS unit out a few times before investing in one. While you may not find it helpful in labor, you may feel it is a great relief prenatally and/or postpartum. Whatever you decide, please check with your provider before using a TENS at any time.
If you are in the Denton, TX area and are interested in hiring a doula for your birth experience, contact me today to schedule a free consultation. If you are interested in learning about more comfort measures in labor, check out my Comfort Measures page.
Photo by Yeza edited by Kristy