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Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• What are menstrual cramps?
• How common are menstrual cramps?
• What is dysmenorrhea?
• What causes menstrual cramps?
• Why are some cramps so painful?
• Can menstrual cramps be measured?
• What other factors influence menstrual cramps?
• What are the symptoms of menstrual cramps?
• How are menstrual cramps diagnosed?
• What is the treatment for common menstrual cramps (primary dysmenorrhea)?
• What if the cramps are very severe?
• Are there surgical solutions?
• What is the treatment of secondary dysmenorrhea?
• What is the long-term outlook (prognosis) for menstrual cramps?
• Menstrual Cramps At A Glance
• Patient Comments: Menstrual Cramps - Adolescent Girls
• Patient Comments: Menstrual Cramps - Experiences
• Patient Comments: Menstrual Cramps - Effective Treatments
• Patient Comments: Menstrual Cramps - Other Causes
• Patient Comments: Menstrual Cramps - Symptoms
• Find a local Obstetrician-Gynecologist in your town
• Menstrual Cramps Index

Each month, the inner lining of the uterus (the endometrium) normally builds up in preparation for a possible pregnancy. After ovulation, if the egg is not fertilized by a sperm, no pregnancy will result and the current lining of the uterus is no longer needed. The woman's estrogen and progesterone hormone levels decline, and the lining of the uterus becomes swollen and is eventually shed as the menstrual flow and is replaced by a new lining in the next monthly cycle.

When the old uterine lining begins to break down, molecular compounds called prostaglandins are released. These compounds cause the muscles of the uterus to contract. When the uterine muscles contract, they constrict the blood supply (vasoconstriction) to the endometrium. This contraction blocks the delivery of oxygen to the tissue of the endometrium which, in turn, breaks down and dies. After the death of this tissue, the uterine contractions literally squeeze the old endometrial tissue through the cervix and out of the body by way of the vagina. Other substances known as leukotrienes, which are chemicals that play a role in the inflammatory response, are also elevated at this time and may be related to the development of menstrual cramps.

Menstrual cramps are caused by the uterine contractions that occur in response to prostaglandins and other chemicals. The cramping sensation is intensified when clots or pieces of bloody tissue from the lining of the uterus pass through the cervix, especially if a woman's cervical canal is narrow.

The difference between menstrual cramps that are more painful and those that are less painful may be related to a woman's prostaglandin levels. Women with menstrual cramps have elevated levels of prostaglandins in the endometrium (uterine lining) when compared with women who do not experience cramps. Menstrual cramps are very similar to those a pregnant woman experiences when she is given prostaglandin as a medication to induce labor.