Effects of noninvasive electroacupuncture at Hegu (LI4) and Sanyinjiao (SP6) acupoints on dysmenorrhea: a randomized controlled trial.

BACKGROUND: This study aimed to evaluate the effects of noninvasive acupoint stimulation therapy with middle-frequency electrical waves on dysmenorrhea in young women.

METHODS: This randomized controlled trial enrolled 66 gynecology patients who had primary dysmenorrhea, which was defined as painful menstruation without pelvic pathology (secondary dysmenorrhea). Pathology was ruled out by gynecological ultrasound examination and serum concentration of CA-125. Subjects were randomly assigned to an experimental group (n=34) and control group (n=32). Main outcome measures included McGill Questionnaire Short-form and numerical rating scale for pain intensity. Acupuncture-like trancutaneous electrical nerve stimulation (AL-TENS) of middle-frequency (1000 Hz-10,000 Hz) was applied at Hegu (LI4) and Sanyinjiao (SP6) points in the experimental group twice weekly for 8 weeks; the control group received AL-TENS on nonacupoints. Pre- and postintervention results were recorded.

RESULTS: Prior to AL-TENS intervention, no significant differences were found in pain scale and pain intensity between experimental and control groups. After AL-TENS intervention, average total pain score in the experimental group was significantly lower than in the control group (experimental group 2.9±1.2, control group 5.4±2.2; p<0.001). Significant differences were observed between experimental and control groups in average change in pain scores between pre- and postintervention (experimental group 4.5±1.9, control group 1.39±2.0; p<0.001). Pain severity at postintervention was also significantly different between groups (p<0.001).

CONCLUSIONS: Noninvasive electro-acupuncture stimulation therapy with middle-frequency electric waves applied at both Hegu (LI4) and Sanyinjiao (SP6) acupoints mitigates pain in dysmenorrhea.