Effect of Using Transcutaneous Electrical Nerve Stimulation (TENS) in Acupuncture Points [Hegu (Li4) and Sanyinjiao (Sp6)] on Duration of the First Stage of Labor

Duration of labor is an important factor affecting pregnancy outcome and fetal and maternal injury. The aim of this study was to compare the effect of transcutaneous electrical nerve stimulation (TENS) on specific acupuncture points for reducing duration of first stage of labor and need to oxytocin augmentation of labor in nulliparous women. This double-blind clinical trial study was performed on 64 nulliparous women in active phase of first stage of labor who hospitalized in Razi hospital of Ghaemshar town, Iran. They were randomly divided into two groups (n=32 in each group). Odd numbers and even numbers of patients were allocated by chance to TENS group and TENS placebo group, respectively. According to TENS on four acupuncture points (Hegu [LI-4] and Sanyinjiao [Sp-6]) (n = 32) or the TENS placebo (n = 32), the current output was titrated for each person separately in 4cm dilated cervix. In TENS group, a burst frequency was set to 100 Hz and pulse duration was set to 250 ms and it was periodically used 20 minutes on and 20 minutes off. In the control group, the TENS unit was not turned on. Duration of first stage of labor, need to oxytocin augmentation of labor, pain severity and satisfaction in two groups were compared. Duration of the first stage was 180 minutes in TENS group and 238 minutes in TENS placebo group (p=0.002) and need for oxytocin augmentation of labor was 16(50%) in TENS group and 25(78.1%) in TENS placebo group (p=0.04) that in TENS group was significantly shorter than TENS placebo group. Pain severity was less (p<0.001) and consent in intervention procedure was more (p<0.001) in TENS group. There was no difference between two groups in terms of Apgar score. According to the results of this study, TENS on acupuncture points can be used as a non-drug method with no side effects on mother and fetus to augment labor and reduce the duration of the first stage of labor.