Endometriosis, which is an abnormal growth of cells that only affects women, is among the most common causes of lower abdominal pain. Other common causes affect both men and women and include chlamydia, a sexually transmitted disease (STD), and cystitis, an inflammation of the bladder. Sometimes a man or a woman may also develop pain in the lower abdomen because of diverticulitis, an inflammation of a pouch in the intestine. Since this pain can be caused by a wide range of conditions, however, an individual may benefit from seeking medical attention for unexplained pain.
Endometriosis is among the most common causes of lower abdominal pain. Only affecting women, endometriosis is a condition in which cells similar to those that line the uterus grow outside the uterus. For example, the cells often grow on a woman's fallopian tunes, ovaries, and the outer part of the uterus. They may also grow onto the lining of a woman’s pelvic cavity and her intestines. Though less common, the cervix, vagina, and bladder may be affected as well.
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Many women who have endometriosis do not experience symptoms of the condition. When a woman does experience symptoms, however, they often include pain in the lower abdomen and difficulty conceiving a child, In most cases, the abdominal pain caused by this condition coincides with a woman’s menstrual period. Sometimes, however, a woman with endometriosis also experiences pain during sexual intercourse, pelvic exams, bowel movements, and urination.
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Chlamydia is also among the most common causes of lower abdominal pain. The condition is a bacterial STD and causes a range of symptoms, including lower abdominal pain and painful urination. A woman with this condition may also experience an abnormal vaginal discharge and notice pain during sexual intercourse. A man with the condition, on the other hand, may note a discharge that comes from his penis and suffer from pain in the testicles. Unfortunately, some people with this STD do not develop symptoms of it and may not know they need treatment.
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The most common causes of lower abdominal pain also include cystitis. Often the result of a urinary tract infection, cystitis is caused by bacteria and marked by inflammation of the bladder and sometimes the urethra, which is the tube that carries urine from the bladder to the outside of the body. Symptoms of cystitis include lower abdominal pain; difficult and painful urination; cloudy, smelly urine; and blood in the urine. Fever may occur as well. Cystitis can affect both men and women, but it more commonly affects women.
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An individual may also develop pain in the lower abdomen because of a pouch that forms in his intestinal wall and then becomes inflamed. This abnormal pouch is called a diverticulum and most commonly affects the large intestine. The symptoms of the condition include severe pain that develops suddenly in the lower left abdominal region, nausea and vomiting, constipation, and fever. Less commonly, abdominal bloating and rectal bleeding may occur.