Many women experience this problem at some point in their lives. It is defined as bleeding from the vagina that is not part of your monthly periods or bleeding that occurs during monthly periods but is heavier than usual.

Some common causes in women of reproductive age are the birth control pill, which can cause bleeding between periods; problems with hormones produced by the thyroid, ovaries, pituitary, or adrenal glands; infections, such as sexually transmitted diseases, of the vagina, cervix, uterus, fallopian tubes, or ovaries; and miscarriage or problems with pregnancy. A miscarriage of an early pregnancy can resemble a heavy period that occurs after the woman has missed at least one period.

Bleeding between cycles that does not last long is often due to scars, tumors, fibroids, or other abnormal tissue on the cervix or uterus. Ovarian cysts are another possibility. Regular, prolonged, heavy bleeding is often caused by growths in the uterine lining, or endometrium. These growths may or may not be cancerous.

Perimenopausal women may bleed off-cycle as part of the gradual onset of menopause. Postmenopausal women should see a doctor immediately if they experience vaginal bleeding since benign or cancerous tumors of the ovaries or uterus are more likely causes.

Other potential culprits are injury to the vagina or reproductive tract during rape or surgery, and the presence of objects such as a tampon stuck in the vagina. Bleeding disorders that affect the whole body, such as leukemia and clotting problems, can cause abnormal vaginal bleeding just as they produce bleeding elsewhere. Vaginal bleeding along with fever, abdominal pain, or unusual mucus or other substances coming from the vagina (known as vaginal discharge) may indicate an infection.

Your doctor is likely to ask you about your recent menstrual periods and if you've noticed anything unusual about them. You will probably have an abdominal and pelvic exam and, if you are of reproductive age, your doctor will also do a pregnancy test. Depending upon your age and the suspected cause of the bleeding, the doctor may remove a small piece of tissue from your uterus and send it to a lab for examination. Ultrasound, in which sound waves are used to form a picture of the internal organs, may also be used.