RESUMEN
OBJECTIVE: To evaluate the efficacy and safety of low-level light therapy in women with primary dysmenorrhea. METHOD: A multicenter prospective, randomized, double-blind, placebo-controlled clinical trial including patients 18-35 years of age with primary dysmenorrhea was undertaken at two university hospitals in South Korea between October 2011 and September 2012. Patients were randomized using a computer-generated sequence to receive low-level light therapy using the Color DNA-WSF device or to receive placebo treatment with a dummy device. The severity of menstrual pain, assessed using a visual analog scale, was the primary outcome and was evaluated at baseline and during every menstrual cycle for 3 months following treatment. Patients who received more than one application of treatment (with a Color DNA-WSF or placebo device) were included in analyses. Patients and investigators were masked to the treatment assignments. RESULTS: Overall, 44 patients were assigned to each group. At the final study visit, the reduction in scores using a visual analog scale was significantly greater in patients who received low-level light therapy (n=41; 4.34±2.22) than among those in the control group (n=38; 1.79±1.73; P<0.001 when adjusted for age) No serious adverse events occurred. CONCLUSION: Low-level light therapy could be an effective, safe treatment modality for women with primary dysmenorrhea. Clinical Trials.gov: NCT02026206.