TENS stands for transcutaneous electrical nerve stimulation. The machine sends mild, painless electrical pulses to your body when you’re having contractions, via sticky electrode pads attached to your back. Many women find this helps reduce the pain experienced during labour.
While it’s not known exactly how a TENS machine helps to relieve pain, it’s thought that the pulses ‘distract’ the nerves that are transmitting pain. Using one may also boost your endorphin levels – your body’s natural form of pain defence.
Most TENS machines have a digital display and several settings, such as a massage setting with a lower-pulse frequency and a more intense mode with stronger pulses.
A good machine will be lightweight and come with a belt clip so you can still move around while using it – many women find that moving around during labour can help them feel more comfortable.
According to the NHS, TENS machines are proven to be effective only during the early stages of labour, when lower back pain is common.
They have not been proven to be effective during the active phase of labour, when you’ll experience longer, stronger and more frequent contractions. However, there’s nothing to stop you continuing to use TENS if you feel it’s working for you.
One of the advantages of a TENS machine is that you can use it wherever you’re planning to give birth.
It’s also a pain relief option you can use while you’re travelling to the maternity unit in labour, or if you need to be transferred to the hospital unexpectedly.
If you’re planning to give birth at a local birth centre or labour ward, check with your midwife if the unit has TENS machines for women in labour to borrow.
Bear in mind, however, that your hospital or birth centre may have a limited number of machines, and if other women are already using them, one may not be available to you when you go into labour.
Because TENS machines tend to be the most useful in the early stages of labour, you may decide to buy or hire one in advance even if you’re planning to go to a maternity unit for the birth, to help you cope with the contractions until you’re in established labour.
While the home birth midwives will be able to supply you with gas and air, you will need to buy or hire a TENS machine if you want to use one during labour.
There are no documented side effects of using a TENS machine, for either you or your baby. There is no time limit on how long you can use it for during birth, and because it doesn’t contain any drugs, as soon as you turn the machine off, the effect of the electrical pulses go away.
Based on Which? survey data in March 2014 of more than 1,200 mums who'd given birth within the last five years, 22% of whom had used a TENS machine in labour.
If you’ve decided that you want the peace of mind of having a TENS machine ready at home before you go into labour, there are several options for how to get hold of one.
You can buy a TENS machine from pharmacies, baby stores and online. It’s important that you check that the TENS machine you’re buying is specifically designed to be used during labour – other versions exist for other types of pain. If in doubt, talk to your midwife at one of your for recommendations of brands.
TENS machines cost around £30 to £70. How much you spend will largely depend on the level of functionality you’d like – some have different preset programs designed to be used at different stages of labour, while pricier models also allow you to log the frequency and length of your contractions.
You could always go halves on one with another pregnant friend, provided your due dates are sufficiently far apart to avoid potential overlap.
Our survey found that almost one in three women borrowed their TENS machine from a friend. This is a great choice in terms of money-saving, and also means your friend can show you how to use the machine – all in all - a very helpful option if it’s available to you.
An alternative option to buying your own TENS machine is to rent one, which can work out slightly cheaper. Hiring one typically costs between £20 and £30 for around six weeks.
Many of the larger pharmacy chains and baby stores offer TENS hire, and they’re also available to hire directly from the NHS or physiotherapists.