TENS stands for Transcutaneous Electrical Nerve Stimulation. Used for many years to treat muscle injury and back pain, TENS works in the same way as massage. A TENS machine emits small pulses that block the pain messages being sent to the brain by your uterus and cervix and also stimulates the release of endorphins.
Two pairs of self-adhesive electrodes are put on your back, one on either side of your spine. These are connected by wires to a small box (about the size of an audio cassette) with dials and a boost button control. The dials control the strength and frequency of the pulses of electricity the machine gives out. You can put the machine in the pocket of a dressing gown. You hold a boost button in your hand, and use this to obtain the maximum output from the machine if you have a really difficult contraction.
TENS is most effective if you try it out during the last weeks of pregnancy and then use it from the start of labour. You will therefore need to hire a unit so that you can practise using it before labour starts. Many hospitals offer a TENS antenatal class to show you how to position the pads and how to get the best out of the machine. You can hire a TENS machine from pharmacies, hospitals, or directly from TENS companies. If you hire a TENS machine from Babycare TENS, they will donate £2.50 to the NCT. Call 0845 230 9737, mentioning NCT. Hires start from £22.95 for 30 days
Most women find TENS moderately effective and simple to use. Some like it better than other forms of pain relief because the mother can control it and there has never been any suggestion that it could harm your baby. First-time mothers may need stronger forms of relief; been-through-it-before mothers report finding it very helpful.