The uterus, considered the strongest muscle in the female body, sits nestled within the pelvic region as part of the female reproductive system. As a muscle, the uterus might experience uterine cramps — painful muscle contractions. Generally, uterine cramps, even severe cramping, are a natural occurrence during menstruation and do not necessarily signify an unhealthy uterus or uterine disease. Besides menstruation, common causes of cramps might include dysmenorrhea, pelvic inflammatory disease (PID) or endometriosis, as well as adenomyosis, cervical stenosis and uterine scarring. Severe uterine cramps during pregnancy are considered abnormal and should always be checked by a medical professional.
Most uterine cramps occur as a result of menstruation, when the uterus is stimulated by various hormones such as oxytocin and prostaglandins. These hormones cause the uterus to contract, producing menstrual cramps that expel the uterus' inner lining, called menses, during the period of menstruation. During strong uterine contractions, the muscle might constrict blood vessels, causing pain.
Some women might experience severe, debilitating cramps before or during menstruation, called dysmenorrhea. Symptoms might include weakness, dizziness, nausea and vomiting and headaches. Dysmenorrhea is not necessarily a complication of the uterus but overproduction of cramp-inducing prostaglandins. Analgesics and hormone therapy relieve or eliminate most uterine cramps caused by dysmenorrhea. Rarely, complications arising from pelvic pathology such as an abnormality or disease of the reproductive system might cause a disease known as "secondary dysmenorrhea," producing severe uterine cramps after monthly menstruation has ceased.
Uterine cramps might be a symptom of underlying conditions or diseases. Fibroids, or benign tumors, that exist in an otherwise healthy uterus might press the inner walls of the uterus, causing cramps. Adenomyosis, a condition in which noncancerous growths extend into the inner walls of the uterus, might stimulate uterine cramping and pain. Scarring from miscarriage, abortion or uterine surgery might cause complications such as uterine adhesion of the inner muscle walls. Endometriosis is an extremely painful condition in which uterine tissue develops elsewhere in the reproductive system, such as on the fallopian tubes or ovaries.
Sexually transmitted diseases can cause uterine cramps. Called pelvic inflammatory disease (PID), uterine cramps and other complications arise from bacterial or viral infections spread throughout the reproductive system. Some women experience uterine cramps from cervical stenosis, a physiological condition in which an unusually small cervix interferes with menstrual flow.
Although they are very common, uterine cramps that are severely debilitating or that occur during pregnancy require medical intervention. Uterine cramps followed by excessive bleeding, such as soaking a feminine pad per hour for several hours, are uncommon. They usually are signs of an underlying condition.
