Korean firm Color Seven has developed a wearable device to relieve menstrual pain using low-level light stimulation called Woman Stress Free. Menstrual pain often afflicts women and girls, but the intensity and impact on quality of life vary widely. A cross-sectioned analytical study found that 84 percent reported menstrual pain which often required medication and even resulted in missing work.

Many women rely on non-steroidal anti-inflammatory drugs, but some prefer to avoid their undesirable side-effects. Other common menstrual pain management methods, according to the National Institutes of Health, include: applying heat with hot water bottles or heating pads, warm baths, or going to the sauna; special diets and dietary supplements; herbal products and herbal teas for medicinal use; homeopathic medicines; and procedures which target pain stimulus such as acupuncture, acupressure or TENS (transcutaneous electrical nerve stimulation). Woman Stress Free adds another alternative to targeting the pain source with low-level light stimulation applied at acupuncture points.

The technology in Woman Stress Free improves blood flow and thereby reduces menstrual cramps with via photo-activated modulation of smooth muscle tissue. The device itself, which is labeled Color DNA, has two light probes that at first look like ear buds attached to the device by a thin wire. The probes are held in place on acupuncture points on the abdomen with adhesive. The light from the probe is emitted for a fixed amount of time. The light stimulation reaches the uterus and increases the secretion of nitrous oxide (NO). The NO spreads over the smooth muscle in the uterine cells and under continuous light stimulation produces a phosphate particle called cyclic guanosine monophosphate (cGMP). These particles continuously flow out and relax the smooth muscles so they receive oxygen and nutrition.

In a study published in the Archives of Gynecology and Obstetrics, subjects using the low-level light therapy (LLLT) showed statistically significant reduction in pain levels after a month and barely any pain after three months. This compares to a placebo group that showed slight pain reduction over time. The study concluded that “skin adhesive LLLT on acupuncture points might be an effective, simple, and safe non-pharmacological treatment for dysmenorrhoea.”

Color 7 also claims Woman Stress Free can help with back pain, nausea, depression, thoracodynia, and stomach ache. The device is approved by the Korean Ministry of Food and Drug Safety, and also for sale in Europe, according to the company. There is currently no FDA clearance for Woman Stress Free.