Menstrual Cramps Explained
Menstrual cramps are menstrual period pains that a woman experiences in her abdomen and pelvis. Cramps should not be confused with premenstrual syndrome (PMS), though many women who experience PMS also experience menstrual cramps and vice versa.
For some women, menstrual cramps are quite mild and may be only barely detectable. They may be very short-lived, too. The feeling of mild cramps may be perceived as a heavy feeling in the abdominal area. Severe cramps, on the other hand, may be so bad that a woman can't attend to her usual duties or activities for many days straight.
Some women have cramps and some never do. It is estimated that more than half of all women experience menstrual cramps to a greater or lesser degree. Of this number, some 15% describe their period cramps as severe. Surveys of teenaged girls showed that more than 90% report period cramps.
The medical name for menstrual cramps is dysmenorrhea. Two types of dysmenorrhea exist: primary and secondary.
Primary dysmenorrhea is cramps with no apparent gynecological problem. A young girl may begin having primary dysmenorrea within half a year to a year after the first period (menarche). Until this point, a girl may not yet be ovulating. Cramps tend to begin only once ovulation (egg release) has begun.
Secondary dysmenorrhea can be traced to a specific gynecological condition that causes menstrual pain. This type of dysmenorrhea may already be present from the very first period, but tends to develop only later.
The menstrual period results when a woman's egg is not fertilized and no pregnancy can occur. The blood excreted during the period consists of the shedding of the uterine lining which had thickened in preparation for a pregnancy that did not come about. As the lining (endometrium) breaks down, chemicals known as prostaglandins are released.
Prostaglandins cause the contraction of the uterine muscles. As the muscles contract, there is a constriction of the blood that circulates to and within the uterine lining. The contractions also mean that oxygen cannot be delivered to the endometrial tissue which causes it to decompose and die.
As the tissue dies off, the uterine contractions help push it out through the neck of the womb and then out of the vagina. During this time, other chemicals called leukotrienes are elevated. Leukotrienes play a role in the inflammatory response. It is believed that heightened levels of leukotrienes may also be involved with the experience of menstrual cramps.