Menstrual cramps are caused by the contraction of the uterus. The flow itself is also part of the problem. Heavy flow or clots in the menstruation have to squeeze out through the small opening of the cervix. This stretching is believed to cause pain as well ⁸.

There are two kinds of menstrual cramps : primary dysmenorrhea and secondary dysmenorrhea.

Primary Dysmenorrhea

Menstrual cramps start a day or so before actual menses. They are felt in the lower or middle abdomen. They can radiate (spread) to the hips, thighs, and back. The severity of cramps varies widely from woman to woman and even between the same woman's periods. Gasto-intestinal symptoms are also common with severe cramps: nausea, vomitting, and diarrhea. Spasms of the leg and abdominal muscles occur with severe cramps.

Secondary Dysmenorrhea

Secondary dysmenorrhea is when cramps are due to an actual disease, such as endometriosis. Secondary is more likely when the problem starts after the age of 25, or when there are other symptoms. The only way to know is to be looked at by a doctor.

Pain killers can alleviate menstrual cramps. Birth control pills can lessen the menstrual flow and solve the problems of dysmenorrhea for many women. Exercise in general has also been shown to help alleviate dysmennorrhea.