Abnormal uterine bleeding may be the result of a hormone imbalance or a lack of ovulation. It may also be the result of weight loss or gain, stress, heavy exercise, infection, use of drugs, miscarriage, or ectopic pregnancy. If your menstrual cycles are less than 21 days, or your period lasts more than 7 or 8 days, or is too heavy, with a gushing of blood or large clots, it is recommended that you see your doctor.

Some women have severe pain with their periods. This is called dysmenorrhea and may be caused by prostaglandin, a hormone made by the lining of the uterus which causes spasms or cramping. Menstrual cramps may also be caused by endometriosis, a condition where the tissue lining the uterus is found in other areas of the body, particularly in the lower abdomen.

Uterine fibroids, non-cancerous growths in or around the uterus, may also cause heavier or more frequent periods and pain or pressure in the abdomen or lower back.

Treatment for menstrual problems may include hormone therapy, drug therapy, or surgery.