Occasionally menstrual flow seems heavier than usual, or a period lasts longer than normal. In general, there is little cause for concern unless you find it necessary to use at least two extra sanitary pads or tampons a day. That means you have lost almost 3 ounces of blood over the course of a period. You should also see your doctor if a period lasts more than seven days, or two periods are spaced less than 21 days apart. Heavy or lengthy uterine bleeding occurring at regular intervals is usually a sign of an underlying physical problem.
When you go to the doctor, he or she will want to know about the frequency and amount of the bleeding, whether it's accompanied by pain or blood clots, what type of contraception you use, and whether you bruise easily or bleed often from places other than the uterus. The doctor will also do a number of tests. Urine and stool testing can detect possible problems in the urinary tract, stomach, and intestines that might cause the bleeding. If you are in your childbearing years, you should also have a pregnancy test, a Pap smear (if you haven't had one in 12 months), a biopsy of the endometrium, and a test for ovulation. If you are not ovulating, the doctor will usually perform a D & C of the endometrium.
In addition, if the physician suspects the bleeding stems from inflammation of the vagina, cervix, endometrium, or fallopian tubes, he or she will perform an internal exam, take a blood count, and may take tests for sexually transmitted diseases.

