Although some pain during menstruation is normal, excessive pain is not. Dysmenorrhea refers to menstrual pain severe enough to limit normal activities or require medication. It may coexist with excessively heavy blood loss (menorrhagia).

• Primary dysmenorrhea refers to menstrual pain that occurs in otherwise healthy women (Wright et al. 2003). This type of pain is not related to any specific problems with the uterus or other pelvic organs.
• Secondary dysmenorrhea is menstrual pain that is attributed to some underlying disease process or structural abnormality either within or outside the uterus (for example, pelvic inflammatory disease, leiomyoma, endometriosis, adhesions, adenomyosis, uterine displacement, or a retroverted uterus). Endometriosis is the most common cause of dysmenorrhea associated with a disease process and is frequently misdiagnosed.