T.E.N.S – Your Labour Companion

The physiological process of labour and birth and how a woman experiences her pain and how she responds to it is very subjective and uniquely individual.

Labour is painful for most women and with this experience comes vulnerability, anxiety, stress, inner strength and resources that they may never have experienced before. 

Many factors play a role in the degree of pain, including the intensity of uterine contractions and the position of the baby as it moves down the birth canal, among others.

Some women are keen to avoid drugs or other medical interventions while others are happy to consider all available options.

Opiates given during labour cross the placenta with the result that some babies are slow to start breathing after they are born. 

Epidurals can lengthen the duration of labour. The anaesthesia may not be complete and the woman may still experience some pain. 

 

TENS (Transcutaneous Electrical Nerve Stimulation) is a safe way to help you cope with pain during labour.

Pain is an emotional experience encompassing neurobiological mechanisms.

In 1965 Melzak and Wall proposed the ‘Gate Theory’ of pain perception. They showed that pain impulses could be overridden and the perception of pain could be altered.

Pain occurs when specialized nerve receptors are stimulated and messages are passed from the nervous system to the brain where they are interpreted as pain.

The brain can only cope with a certain amount of information at once though. Sensation impulses from the nerves have priority over pain signals. When a TENS unit is used you feel it strongly and the pain gets put to the ‘back of your mind’. You perceive the pain as less intense. 

TENS (Transcutaneous Electrical Nerve Stimulation) is simply a means of stimulating your bodys own natural defences against pain.

It delivers tiny, safe, electrical signals through conductive pads to stimulate the nerves under your skin.

These signals act in two ways: They block the transmission of pain signals travelling in nearby nerves, stopping them going through the spinal cord to the brain, and they send their own message to the brain, triggering the release of endorphin – the bodys own natural painkiller.

 

TENS stimulates endorphin release (the body’s natural painkillers) to help reduce pain.

Endorphins (or 'endogenous opiates') are manufactured by our bodies in the presence of pain and act as a natural analgesic.

There is some evidence to suggest that the pregnant woman's body starts to produce more endorphins just prior to labour.

Endorphins are released by the ends of the 'descending nerve fibres' or 'going down' fibres that come down the spinal cord from the brain. 

When we feel pain, the descending nerve fibres release endorphins at the spinal cord, where they meet the sensory nerves carrying the 'pain messages' from our body. This local release of endorphins by the nerves inhibits some or all of the pain messages going up to the brain.

Endorphins can therefore empower women and provide a positive memory and experience associated with labour and birth.

 

Using TENS in childbirth may help you stay calm and comfortable which reduces the possibility of medical intervention and further complications. 


It feels like a pleasant tingling sensation on the skin where the electrode pads are placed.

It distracts the brain from labour sensations, blocking pain messages and empowers you to cope with labour more effectively. 

In labour the electrodes from the TENS machine are usually attached to the lower back (and women themselves control the electrical currents using a hand-held device) but TENS can also be applied to acupuncture points or directly to the head.

 

Benefits of using TENS machine during labour: 

  • Drug FREE pain control
  • Instant long lasting pain relief 
  • No side effects or drowsiness 
  • Affordable machine, that can be used at home when contractions start
  • You can help manage contractions with the press of a button
  • You can stay mobile and use it in conjunction with other methods/drugs for pain relief 

TENS is also a safe and viable non-pharmacological pain relief method to be employed for pain relief after episiotomy (surgical cut during the crowning phase of a vaginal birth).

In a recent controlled randomised study conducted in a maternity ward in Brazil, high-frequency TENS treatment significantly reduced pain intensity immediately after its use and 60 min later.

 

TENS can provide effective pain relief from afterpains.

Breast-feeding in the postpartum period is known to induce intense uterine contractions with pain in the lower abdomen.

The afterpains that come from your uterus contracting back to its smaller size after birth can be as painful as labour and tend to get worse with each pregnancy. 

Twenty-one newly delivered women participated in a single-blind trial, 12 women received high intensity, high-frequency TENS (HI TENS) and 9 women received low intensity, high-frequency TENS (LI TENS). The women treated with HI TENS, experienced significantly less postpartum pain and discomfort to those treated with LI TENS.

 

Further Reading:

 

Refernces:

“High-frequency TENS in post-episiotomy pain relief in primiparous puerpere: A randomized, controlled trial”, A. Pitangui, Ligia de Sousa, F. Gomes, C. Ferreira, A. Nakano, Journal of Obstetrics and Gynaecology Research, 2012

“A comparison of high- versus low-intensity, high-frequency transcutaneous electric nerve stimulation for painful postpartum uterine contractions”, M. Olsen, H. Elden, E. Janson, H. Lilja, E. Stener-Victorin, Acta Obstetricia et Gynecologica Scandinavica, 2007