The use of transcutaneous electrical nerve stimulation (TENS) for pain relief in labour: a review of the evidence.

OBJECTIVE: to assess the effects of transcutaneous electrical nerve stimulation (TENS) for pain relief in labour. SEARCH METHODS: studies were identified from a search of the Cochrane Pregnancy and Childbirth Group\'s Trials Register (November 2008). SELECTION CRITERIA: randomised controlled trials comparing women receiving TENS for pain relief in labour vs routine care or placebo devices. All types of TENS machines were included. DATA COLLECTION AND ANALYSIS: two review authors assessed all trials identified by the search strategy, carried out data extraction and assessed risk of bias. RESULTS: 14 studies including 1256 women were included: 11 examined TENS applied to the back, two to acupuncture points and one to the cranium. Overall, there was little difference in satisfaction with pain relief or in pain ratings between TENS and control groups, although women receiving TENS to acupuncture points were less likely to report severe pain (risk ratio 0.41, 95% confidence interval 0.32-0.55). The majority of women using TENS would use it again in a future labour. There was no evidence that TENS had any impact on interventions and outcomes in labour. There was little information on outcomes for mothers and infants. No adverse events were reported. CONCLUSIONS: there is only limited evidence that TENS reduces pain in labour and it does not seem to have any impact on other outcomes for mothers or infants. The use of TENS at home in early labour has not been evaluated. Although the guidelines of the National Institute for Health and Clinical Excellence recommend that TENS should not be offered to women in labour, women appear to be choosing it and midwives are supporting them in their choice. Given the absence of adverse effects and the limited evidence base, it seems unreasonable to deny women that choice. More robust studies of effectiveness are needed. Copyright © 2009 Elsevier Ltd. All rights reserved.