According to the Mayo Clinic: "If you're a woman, chances are you've dealt with menstrual cramps - even if you've never heard of "dysmenorrhea," the medical term for them. Menstrual cramps are dull or throbbing pains in the lower abdomen. Many women experience menstrual cramps just before and during their menstrual periods. For some women, the discomfort is merely annoying. For others, it can be severe enough to interfere with everyday activities for a few days every month. Menstrual cramps are classified as primary dysmenorrhea or secondary dysmenorrhea. Primary dysmenorrhea involves no physical abnormality and usually begins six months to a year after you begin menstruating. Secondary dysmenorrhea involves an underlying physical cause, such as endometriosis or uterine fibroids. If you have primary dysmenorrhea, there are some measures you can take to ease the discomfort. You can also rest assured that cramps tend to decrease in intensity as you get older and often disappear after pregnancy. For secondary dysmenorrhea, managing your cramps involves treating the underlying cause." One of the easiest, most effective methods to relieve the cramping and pain is the soothing moist heat of a Thermophore®. The Thermophore® Classic™heat therapy system has long been known as a convenient, effective method of providing penetrating moist heat to help relieve all types of pain. It reaches much higher temperatures than ordinary heating pads, and is even classified as a medical device by the FDA. There is No Need to add any water to the unit - atmospheric moisture is captured by the special flannel cover and released when the intense heat is activated.