Dysmenorrhea is the technical term for menstrual cramps that are severe enough to interfere with a woman's normal functioning. It is the most common gynecologic complaint, affecting at least 50 percent of menstruating women. One to 2 percent of women experience severe, incapacitating symptoms.

Primary dysmenorrhea -- menstrual pain that occurs in the absence of underlying disease -- is thought to be related to the release of hormones called prostaglandins during menstruation, which can cause excessive contractions of the uterus. The pain is most severe at the start of the menstrual period and lasts 12 to 72 hours. It is wavelike and cramping in nature and may spread to the back. Accompanying symptoms may include nausea, vomiting, diarrhea, fatigue, headache, and shortness of breath.

Secondary dysmenorrhea is caused by pelvic diseases, such as endometriosis, fibroids, pelvic infections, prior surgery, or cervical stenosis. The pain of secondary dysmenorrhea usually begins earlier in the menstrual cycle and continues beyond the end of the menstrual period. Additional symptoms may be present depending on the underlying disease.

Risk Factors

The following factors are associated with risk for primary dysmenorrhea. Risk factors for secondary dysmenorrhea depend on the underlying disease.

• Age: The most intense, disabling symptoms occur during adolescence and typically decrease with age.
• Sedentary lifestyle

Factors that decrease the risk of dysmenorrhea include use of oral contraceptive pills and previous pregnancies

Dysmenorrhea: Diagnosis and Treatment

Diagnosis

• A complete history and physical is necessary for all patients, including menstrual, gynecologic, sexual, and dietary history. Abdominal, pelvic, and rectal examinations may reveal conditions that are responsible for the pain.
• Laboratory testing may include a pregnancy test, Pap smear, urine analysis, and blood tests.
• Testing for sexually transmitted diseases, including cultures for gonorrhea and Chlamydia, is normally conducted. However, negative cultures do not exclude pelvic infection.
• Pelvic and vaginal ultrasound may be necessary to check for underlying disorders, such as fibroids.
• In some cases, surgical laparoscopy may be needed for the diagnosis and removal of fibroids, endometriosis, cysts, or other abdominal or pelvic disorders.

Treatment

Primary dysmenorrhea may require a multidisciplinary approach that may include medical, lifestyle, and nutritional interventions.

• Nutritional interventions, such as a low-fat vegan diet, vitamin E, magnesium, and other supplements, decreased alcohol and caffeine intake, and weight loss may be useful (see Nutritional Considerations below).
• Regular exercise reduces blood estrogen concentrations, which would be expected to reduce the risk of dysmenorrhea. In some studies, women who exercise appear to have milder menstrual symptoms, compared with women who do not exercise.
• Smoking cessation may be helpful.
• Heat applied to the lower abdomen may be as effective as acetaminophen (Tylenol) and ibuprofen for pain relief.
• Acupuncture and electrical nerve stimulation may be beneficial. Limited evidence from controlled trials indicates that acupuncture produces significant pain relief and decreases the need for pain medications.
• Nonsteroidal anti-inflammatory drugs (e.g., ibuprofen and naproxen) are often effective in treating pain. Treatment is more effective if begun before the expected onset of symptoms and continued throughout the menstrual period.
• Oral contraceptive pills are often effective.
• Other medications, including calcium channel blockers, nitroglycerin, and nitric oxide, are under investigation.
• Women who do not respond to medications should be considered for treatment of endometriosis.
• In cases of secondary dysmenorrhea, treatment is based on the underlying problem. NSAIDs and oral contraceptive pills may be useful in some patients.

 Dysmenorrhea: Nutritional Considerations

Diet therapies have not been extensively studied. However, evidence supports a role for diet changes that alter estrogen concentrations or estrogen activity. These interventions may also involve the inhibition of hormones (prostaglandins) that cause contraction of the muscles of the uterus.

• A low-fat vegetarian diet may reduce dysmenorrhea symptoms: High-fiber, plant-based diets are associated with reduced blood estrogen concentrations. In a placebo-controlled trial, a low-fat vegan diet was shown to reduce the duration and severity of menstrual pain. To be effective, it appears that the diet should be carefully followed, excluding animal products and added oils. Another possible protective aspect of these diets is their high content of phytoestrogens. Vegetarian diets also have higher amounts of omega-3 fatty acids, which may decrease inflammation.
• Dietary supplements: A published review of available evidence supports the use of thiamine, magnesium, and vitamin E in the treatment of dysmenorrhea. A recent controlled trial of vitamin E came to similar conclusions.