Skin adhesive low-level light therapy for dysmenorrhoea: a randomized, double-blind, placebo-controlled, pilot trial

Purpose The cause of dysmenorrhoea is an abnormal function of smooth muscles in the uterus due to long-term deficient blood supply into smooth muscle tissue. The purpose of this study was to evaluate the effectiveness of skin adhesive low-level light therapy (LLLT) in participants with dysmenorrhoea. Methods Thirty-one women were included in this randomized, double-blind, placebo-controlled, pilot trial. Twenty-one women were treated with active LLLT and ten women were treated with placebo one. The therapy was performed in a laboratory room for 20 min a day over a period of 5 days prior to the expected onset of menstruation. The outcome was measured using a visual analog scale (VAS) for each participant’s dysmenorrhoeal pain severity. VAS of each subject was measured every month for 6 months. Results In the active LLLT group, 16 women reported successful results during their first menstrual cycle just after active LLLT and 5 women had successful results from the second menstrual cycle after active LLLT. The pain reduction rate was 83 % in the active LLLT group, whereas there was only a slight and temporary reduction in pain in the placebo LLLT group. Changes of VAS within 6 months of LLLT showed statistical significance ( p = 0.001) over placebo control. Conclusions Our study suggests that skin adhesive LLLT on acupuncture points might be an effective, simple and safe non-pharmacological treatment for dysmenorrhoea.