title: Transcutaneous electrical nerve stimulation (TENS) reduces pain and postpones the need for pharmacological analgesia during labour: a randomised trial.
abstract: OBJECTIVE
  In the active phase of the first stage of labour, does transcutaneous electrical nerve stimulation (TENS) relieve pain or change its location? Does TENS delay the request for neuraxial analgesia during labour? Does TENS produce any harmful effects in the mother or the foetus? Are women in labour satisfied with the care provided?
  
  
  METHODS
  Randomised trial with concealed allocation, assessor blinding for some outcomes, and intention-to-treat analysis.
  
  
  METHODS
  Forty-six low-risk, primigravida parturients with a gestational age > 37 weeks, cervical dilation of 4cm, and without the use of any medications from hospital admission until randomisation.
  
  
  METHODS
  The principal investigator applied TENS to the experimental group for 30minutes starting at the beginning of the active phase of labour. A second investigator assessed the outcomes in both the control and experimental groups. Both groups received routine perinatal care.
  
  
  METHODS
  The primary outcome was pain severity after the intervention period, which was assessed using the 100-mm visual analogue scale. Secondary outcomes included: pain location, duration of the active phase of labour, time to pharmacological labour analgesia, mode of birth, neonatal outcomes, and the participant's satisfaction with the care provided.
  
  
  RESULTS
  After the intervention, a significant mean difference in change in pain of 15mm was observed favouring the experimental group (95% CI 2 to 27). The application of TENS did not alter the location or distribution of the pain. The mean time to pharmacological analgesia after the intervention was 5.0hours (95% CI 4.1 to 5.9) longer in the experimental group. The intervention did not significantly impact the other maternal and neonatal outcomes. Participants in both groups were satisfied with the care provided during labour.
  
  
  CONCLUSIONS
  TENS produces a significant decrease in pain during labour and postpones the need for pharmacological analgesia for pain relief.
  
  
  BACKGROUND
  NCT01600495.
authors.affiliation: Department of Gynecology and Obstetrics.
authors.forename: Licia Santos
authors.initials: LS
authors.lastname: Santana
authors.affiliation: Department of Gynecology and Obstetrics.
authors.forename: Rubneide Barreto Silva
authors.initials: RB
authors.lastname: Gallo
authors.affiliation: Department of Health Sciences Applied to the Locomotor Apparatus, Ribeirão Preto Medical School, University of São Paulo, Brazil.
authors.forename: Cristine Homsi Jorge
authors.initials: CH
authors.lastname: Ferreira
authors.affiliation: Department of Gynecology and Obstetrics.
authors.forename: Geraldo
authors.initials: G
authors.lastname: Duarte
authors.affiliation: Department of Gynecology and Obstetrics.
authors.forename: Silvana Maria
authors.initials: SM
authors.lastname: Quintana
authors.affiliation: Department of Gynecology and Obstetrics.
authors.forename: Alessandra Cristina
authors.initials: AC
authors.lastname: Marcolin
mesh_terms: D000293:Adolescent; D000698:Analgesia / Q000379:methods*; D005260:Female; D006801:Humans; D048949:Labor Pain / Q000628:therapy*; D059408:Pain Management / Q000379:methods*; D010147:Pain Measurement; D017060:Patient Satisfaction; D011247:Pregnancy; D004561:Transcutaneous Electric Nerve Stimulation; D016896:Treatment Outcome; D055815:Young Adult
keywords: Analgesia; Labour pain; Physical therapy modality; Randomised controlled trial; Transcutaneous electrical nerve stimulation