Objective：To investigate the efficacy of transcutaneous electrical nerve stimulation（TENS）on four specific acupuncture points Hegu（LI4）,Neiguan（PC6）,Danshu（BL19）and Weishu（BL21）for reducing pain in labor.Methods：A total of 160 voluntary nulliparous women who were willing to receive TENS for analgesia were assigned to the treatment group after cervical dilation of more than 2 cm.Another 145 matched nullipara were recruited as the control group.Visual analogue scale（VAS）was used to assess the pain before and 0.5 h after the application of TENS.Then,VAS was assessed every one hour until delivery.Percentage of VAS score decreased by〉25%was the primary outcome,the delivery mode and neonatal outcome were measured as secondary outcomes.Adverse reactions were also recorded during TENS.Results：The percentage of VAS score decreased by〉25%was 68.6%in the TENS treatment group.Maternal delivery mode and neonatal outcomes were not significantly different between the two groups.In addition,the incidence of postpartum hemorrhage in the TENS treatment group was less than the control group（P〈0.05）.There was no adverse reaction recorded with TENS on acupoints.Conclusion：As a novel and non-invasive approach,TENS on specific acupoints including Hegu（LI4）,Neiguan（PC6）,Danshu（BL19）and Weishu（BL21）was an effective method for analgesia in labor.
