Primary dysmenorrhea is menstrual pain associated with menstrual cycles in the absence of pathologic findings. Primary dysmenorrhea pain usually begins within 1–2 years after the menarche and may become progressively more severe. The frequency of cases increases up to age 20 and then decreases with both increasing age and parity. Fifty percent to 75% of women are affected by dysmenorrhea at some time and 5–6% have incapacitating pain.
Primary dysmenorrhea is low, midline, wave-like, cramping pelvic pain often radiating to the back or inner thighs. Cramps may last for 1 or more days and may be associated with nausea, diarrhea, headache, and flushing. The pain is produced by uterine vasoconstriction, anoxia, and sustained contractions mediated by prostaglandins. The pelvic examination is normal between menses; examination during menses may produce discomfort, but there are no pathologic findings.
NSAIDs (ibuprofen, ketoprofen, mefenamic acid, naproxen) and the cyclooxygenase (COX)-2 inhibitor (celecoxib) are generally helpful. The medication should be started 1–2 days before expected menses. Symptoms can be suppressed with use of combined hormonal contraceptives, DMPA, etonogestrel subdermal implant (Nexplanon), or the levonorgestrel-releasing IUD. Continuous use of oral contraceptives can be used to suppress menstruation completely and prevent dysmenorrhea. For women who do not wish to use hormonal contraception, other therapies that have shown at least some benefit include local heat; thiamine, 100 mg/day orally; vitamin E, 200 units/day orally from 2 days prior to and for the first 3 days of menses; and high-frequency transcutaneous electrical nerve stimulation.
2. OTHER CATEGORIES OF PELVIC PAIN
Unlike primary dysmenorrhea, other causes of pelvic pain may or may not be associated with the menstrual cycle but are more likely to be associated with pelvic pathology. Conditions such as endometriosis, adenomyosis, fibroids, PID, or other anatomic abnormalities of the pelvic organs, including the bowel or bladder, may present with symptoms during the menstrual cycle or of a more chronic nature.
The history and physical examination may suggest endometriosis, adenomyosis, or fibroids as causes of pelvic pain. Other causes include PID, tubo-ovarian abscess, submucous myoma(s), IUD use, cervical stenosis with obstruction, or blind uterine horn (rare). Careful review of bowel or bladder symptoms besides pain should be done to exclude another pelvic organ source.
Targeted physical examination may help identify the anatomic source of pelvic pain. PID should be considered in sexually active women with pelvic pain and examination findings of cervical motion tenderness, uterine, or adnexal tenderness without another explanation for the pain. Pelvic imaging is useful for diagnosing the presence of uterine fibroids or other anomalies. Adenomyosis (the presence of endometrial glands and stroma within the myometrium) may be detected with ultrasound or MRI. Laparoscopy may help diagnose endometriosis ...