Pathophysiology
Clinical meaning
Dysmenorrhea is painful menstruation caused by excessive uterine contractions. Primary dysmenorrhea occurs without underlying pelvic pathology and is caused by overproduction of prostaglandins (PGF2α and PGE2) from the shedding endometrium. These prostaglandins cause intense myometrial contractions that compress uterine blood vessels, leading to tissue ischemia and pain. Secondary dysmenorrhea is caused by an underlying condition such as endometriosis, adenomyosis, or uterine fibroids. Primary dysmenorrhea typically begins 1-2 years after menarche when ovulatory cycles are established, while secondary dysmenorrhea may develop later in life.