Hello, Dysmenorrhea is the medical term for the painful cramps that may occur immediately before or during the menstrual period. Primary dysmenorrhea is another name for common menstrual cramps. Cramps usually begin one to two years after a woman starts getting her period. Pain usually is felt in the lower abdomen or back.  Non-steroidal anti-inflammatory drugs(NSAIDs) are effective in relieving the pain of primary dysmenorrhea.