July 10, 2009

Dysfunctional Uterine Bleeding

Dysfunctional uterine bleeding is abnormal bleeding resulting from changes in the hormonal control of menstruation.

Bleeding occurs frequently or irregularly, lasts longer, or is heavier.

This disorder is diagnosed when the physical examination, ultrasonography, and other tests have ruled out the usual causes of vaginal bleeding.

An endometrial biopsy is usually done.

The bleeding can usually be controlled with estrogen plus a progestin or sometimes with either alone.

If the biopsy detects abnormal cells, treatment involves high doses of a progestin and sometimes removal of the uterus.

Dysfunctional uterine bleeding occurs most commonly at the beginning and end of the reproductive years: 20% of cases occur in adolescent girls, and more than 50% occur in women older than 45. In about 90% of cases, the ovaries do not release an egg (ovulate). Thus, pregnancy is impossible.

Dysfunctional uterine bleeding commonly results when the level of estrogen remains high instead of decreasing as it normally does after the egg is released and not fertilized. The high estrogen level is not balanced by an appropriate level of progesterone. In such cases, no egg is released. As a result, the lining of the uterus (endometrium) continues to thicken (instead of breaking down and being shed normally as a menstrual period). This condition is called endometrial hyperplasia. The lining is then shed incompletely and irregularly, causing bleeding. Bleeding is irregular, prolonged, and sometimes heavy. This type of bleeding is common among women who have polycystic ovary syndrome and occurs in some women with endometriosis. A high estrogen level not balanced by progesterone increases the risk of endometrial cancer, even in young women.

Dysfunctional uterine bleeding may be an early sign of menopause.


Bleeding may differ from typical menstrual periods in the following ways:

Occur more frequently (less than 21 days apart—polymenorrhea)

Last longer or involve more blood loss than menses (more than 7 days or more than about 3 ounces—menorrhagia)

Occur frequently and irregularly between periods (metrorrhagia)

Bleeding during regular menstrual cycles may be abnormal, or bleeding may occur at unpredictable times. Some women have symptoms associated with menstrual periods, such as breast tenderness and bloating.

If bleeding continues, women may develop an iron deficiency and sometimes anemia.


Dysfunctional uterine bleeding is suspected when bleeding occurs at irregular times or in excessive amounts. It is diagnosed when all other possible causes of vaginal bleeding have been excluded. These causes include abnormalities of the genital organs (including polycystic ovary syndrome), inflammation, blood clotting disorders, pregnancy, complications of pregnancy, and use of contraceptives or certain drugs.

To establish that bleeding is abnormal, doctors ask questions about the pattern of bleeding. To exclude other possible causes, they ask about other symptoms and possible causes (such as use of drugs, the presence of other disorders, fibroids, and complications during pregnancies). A physical examination is also done. A complete blood cell count can help doctors estimate how much blood has been lost and whether anemia is present.

Tests to check for possible causes may be done based on the findings during the interview and physical examination. For example, blood tests to determine how fast blood clots or to measure hormone levels may be done.

Transvaginal ultrasonography (using a thin probe inserted through the vagina and into the uterus) is often used to check for growths in the uterus and to determine whether the uterine lining is thickened.

If the risk of cancer of the uterine lining (endometrial cancer) is high, an endometrial biopsy is done before drug treatment is started. Risk is increased in women with the following:

.Age 35 or older
.Polycystic ovary syndrome
.High blood pressure
.Bleeding that is persistent, irregular, or heavy despite treatment
.Thickening of the uterine lining (detected by ultrasonography)
.Inconclusive findings during ultrasonography

Most women with dysfunctional uterine bleeding have one or more of these conditions and thus require a biopsy.


Treatment depends on how old the woman is, how heavy the bleeding is, whether the uterine lining is thickened, and whether the woman wishes to become pregnant. It focuses on controlling the bleeding and, if needed, preventing endometrial cancer.

When the uterine lining is thickened but its cells are normal, hormones may be used to control bleeding.

For heavy bleeding, a combination oral contraceptive (a birth control pill with estrogen and a progestin) may be used.

For very heavy bleeding, estrogen may be given intravenously until the bleeding stops. Sometimes a progestin is given by mouth at the same time or started 2 or 3 days later. Occasionally, bleeding is so heavy that fluids are given intravenously and a blood transfusion is needed. Very rarely, a catheter needs to be inserted into the uterus and inflated to put pressure on the bleeding vessels and thus stop the bleeding.

Bleeding usually stops in 12 to 24 hours. After bleeding stops, low doses of the oral contraceptive may then be prescribed for at least 3 months to prevent the bleeding from recurring.

Some women should not be treated with a combination oral contraceptive or estrogen. They include postmenopausal women and women with significant risk factors for a heart or blood vessel disorder. For these women, an intrauterine device (IUD) that contains a progestin may be used, or a progestin may be given alone by injection or by mouth. These treatments may also be used when those that include estrogen are ineffective.

If women wish to become pregnant and bleeding is not too heavy, they may be given clomiphene (a fertility drug) by mouth instead of hormones. It stimulates ovulation.

If the uterine lining remains thickened or the bleeding persists despite treatment with hormones, dilation and curettage (D and C) is usually needed. In this procedure, tissue from the uterine lining is removed by scraping. This procedure may reduce bleeding, but in some women, it causes scarring of the endometrium (Asherman's syndrome), which can cause menstrual bleeding to stop (amenorrhea).

If the uterine lining contains abnormal cells (particularly in women who are older than 35 and who do not want to become pregnant), treatment begins with a high dose of a progestin. A biopsy is done after 3 to 6 months of treatment. If it detects abnormal cells, a hysterectomy is done because the abnormal cells may become cancerous. If women are postmenopausal, a progestin is not used. Hysterectomy is done.

Adapted from: Merck & Co., Inc.