Primary and secondary dysmenorrhea
Primary dysmenorrhea doesn’t have any specific organic cause. Primary dysmenorrhea usually appears within one to two years after the first menstrual period and it may persist even after the age of 40.
During the menstrual period, when the ovulation period is near the beginning, the prostaglandin production, a substance that acts in the uterus, starts. Many times, for unknown reasons, there is too much prostaglandin production, which causes menstrual cramps. This is the primary dysmenorrhea.
Secondary dysmenorrhea usually is caused by some disease or disorder that affects the pelvic organs (ovaries, uterine tubes, uterus, etc.) and usually occurs many years after the first menstrual period. Therefore, several gynecological conditions may cause dysmenorrhea, such as cysts, ovarian and uterus changes, including myomas (non-malignant tumor), endometriosis (growth beyond or outside the uterus of tissue resembling endometrium) and due to IUD usage.