This results in increased rhythmic uterine contractions from vasoconstriction of the small vessels in the uterine wall. Increased prostaglandins synthesis also may be responsible for the distressing gastrointestinal symptoms occasionally present. Secondary dysmenorrhea may include the effects of excess prostaglandins, as well as excessive uterine contractions secondary to an underlying pathology such as endometriosis, adenomyosis, infection, or another underlying disease. Dysmenorrhea is a leading cause of absenteeism for women younger than 30 years. Diagnose dysmenorrhea only after serious causes of pelvic pain are excluded.
Secondary dysmenorrhea can occur with an anovulatory cycle years after the onset of menarche.
Pain with primary dysmenorrhea usually starts within 24 hours of menses and may last for 48-72 hours. In secondary dysmenorrhea, the patient may have onset of pain a week or more prior to the onset of menses, and pain may continue for a few days after cessation of flow. History should include a review of systems with particular attention to gynecologic and gastrointestinal systems. Pay particular attention to the description of pain. Gynecologic history should include menarche, abnormal vaginal bleeding, discharge, dyspareunia, and infertility.