Chapter 20 Dysmenorrhea: Primary and Secondary
INTRODUCTION
Description: Primary dysmenorrhea is painful menstruation without a clinically identifiable cause. Secondary dysmenorrhea is recurrent menstrual pain resulting from a clinically identifiable cause or abnormality.
Prevalence: Of all women, 10% to 15% are unable to function because of pain; 90% have discomfort with at least one cycle.
Predominant Age: Late teens to early 30s (primary), prevalence follows the occurrence of underlying conditions for secondary dysmenorrhea. Dysmenorrhea that begins after the age of 25 is most often secondary.
ETIOLOGY AND PATHOGENESIS
Causes: Primary—increased production of prostaglandin F2α (PGF2α) resulting in increased uterine contractions (dysrhythmic) and markedly elevated intrauterine pressures (up to 400 mm Hg); possible increased sensitivity to PGF2α as well. Secondary—uterine (adenomyosis, cervical stenosis and cervical lesions), congenital abnormalities (outflow obstructions, uterine anomalies), infection (chronic endometritis), intrauterine contraceptive devices, myomas (generally intracavitary or intramural), polyps; extrauterine (endometriosis, inflammation, and scarring [adhesions]); nongynecologic causes (musculoskeletal, gastrointestinal, urinary); “pelvic congestive syndrome” (debated); psychogenic (rare); tumors (myomas, benign or malignant tumors of ovary, bowel, or bladder).
