Quick answer: TENS is non-invasive, drug-free and widely considered safe. It has been used clinically for over 50 years, and a Cochrane review of 17 labour trials found no adverse events for mothers or babies. A small group should seek medical advice before using TENS: people with a pacemaker or implanted electrical device, epilepsy, or a heart condition. TENS should not be used in water or while driving.
Why TENS is considered safe
TENS works on the surface, stimulating nerves through the skin with a mild, battery-powered current. Nothing enters the body, nothing is ingested, and the effect stops when the device is switched off. That profile is why TENS has remained in clinical use for over five decades and why it is a first-line recommendation for drug-free labour pain relief. Elle TENS devices are registered on the ARTG (number 225921) and independently assessed for electrical safety and biocompatibility.
What the evidence shows
The Cochrane systematic review of TENS for labour pain, covering 17 randomised trials and 1,466 women, reported no adverse events for mothers or babies in any included trial. For everyday use, decades of physiotherapy practice tell the same story: side effects are rare and minor, most commonly temporary skin redness under the pads.
Who should check with a doctor first
A small number of situations call for medical advice before using TENS. These relate to the electrical pulses, not to any effect on a baby during labour.
- A pacemaker or any implanted electrical or metal device. The pulses can potentially interfere with implant function.
- Epilepsy. Discuss with your doctor or specialist first.
- A heart condition or heart rhythm problem.
- Early pregnancy. TENS is well established for labour itself; for other pain earlier in pregnancy, check with your midwife or doctor before use.
Where pads should not go
Keep pads away from the front or sides of the neck, the temples, the eyes and mouth, broken or irritated skin, varicose veins, and numb areas where you cannot feel the intensity. Do not place pads on the chest and upper back at the same time. For labour, the correct positions are on the lower back, and every Elle TENS hire includes a placement chart.
Skin sensitivity and electrode quality
The most common minor side effect of TENS is skin irritation under the pads, and research shows it is usually a reaction to allergens in low-quality electrode adhesives (Johnson, Pain Management, 2025). This is why electrode quality matters. Elle TENS devices come with Babycare-certified hypoallergenic electrodes that are biocompatibility-tested for exactly this reason, and reusable pads should be stored on their backing paper and replaced when the gel wears.
Practical rules
Two simple no-gos: do not use TENS in water (take it off before the bath, shower or birth pool, and put it back on after), and do not use it while driving or operating machinery. In labour, remove TENS if a fetal scalp electrode is placed or when an epidural is being sited; your midwife will guide you.
Frequently Asked Questions
What are the side effects of a TENS machine?
For most people, none. The most common is temporary skin redness or irritation under the pads, usually linked to electrode adhesive quality, which is why certified hypoallergenic electrodes matter. There is no grogginess, no drug interaction, and no lasting effect after the device is switched off.
Can TENS cause harm if turned up too high?
The intensity range of a certified TENS device is designed to stay within safe limits. A setting that is too high simply feels uncomfortable, and you turn it down. Always increase gradually and stay within what feels strong but comfortable.
Can I use TENS while pregnant, before labour?
TENS is well established for labour itself. For other pain earlier in pregnancy, speak with your midwife or doctor before using TENS, as it may not be recommended in early pregnancy.
Can I use a TENS machine with a pacemaker?
Not without medical clearance. The electrical pulses can potentially interfere with pacemakers and other implanted devices. Speak with your cardiologist or device clinic first.
Is TENS safe for my baby during labour?
Yes. The electrodes sit on your lower back, away from your abdomen, and the current works locally on the nerves in your back. A Cochrane review of 17 trials found no adverse events for mothers or babies.
Sources
- Dowswell T, Bedwell C, Lavender T, Neilson JP. Transcutaneous electrical nerve stimulation (TENS) for pain management in labour. Cochrane Database of Systematic Reviews 2009;(2):CD007214.
- Johnson MI. Skin reactions associated with self-adhesive electrodes used for TENS. Pain Management. 2025;15(10):671-676.
