Abnormal Uterine Bleeding (AUB)

(Dysfunctional Uterine Bleeding)

Reviewed/Revised Nov 2023
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What is abnormal uterine bleeding?

Your uterus (womb) normally bleeds during your monthly period. Abnormal uterine bleeding is bleeding that's different from your usual period.

  • You may have bleeding between periods, a period that lasts longer than usual, heavier bleeding during your period, or bleeding after you've stopped having periods

  • Abnormal uterine bleeding is usually caused by problems with levels of the female hormones estrogen and progesterone

  • Less often, abnormal uterine bleeding is caused by growths in the uterus, including fibroids and cancer

  • Abnormal uterine bleeding is most common in teens (who have just started having periods) and women over 45 (who are getting closer to menopause)

  • Doctors may give you hormones or other medicine to control your bleeding

What causes abnormal uterine bleeding?

Abnormal uterine bleeding is often caused by problems with your female hormone levels. This can happen:

Thyroid gland disorders and pituitary gland disorders also can affect your female hormones and cause bleeding.

Sometimes, abnormal bleeding is caused by growths in or around your uterus, such as:

What are the symptoms of abnormal uterine bleeding?

In women with abnormal uterine bleeding, bleeding may differ from typical menstrual periods in the following ways:

  • Occurs more frequently (fewer than 24 days apart)

  • Varies in how many days it lasts

  • Lasts longer than 8 days

  • Occurs between periods or does not occur regularly

  • Involves more blood loss

Too much bleeding can lead to a low blood count (anemia), which may make you feel weak and tired.

How can doctors tell if I have abnormal uterine bleeding?

Doctors usually do tests to look for disorders that could be causing your bleeding, including:

  • Blood tests, including a blood count and certain hormone levels

  • Pregnancy test

  • Transvaginal ultrasonography (when doctors place an ultrasound device in your vagina to look at your uterus, ovaries, cervix, and vagina)

If you have risk factors for cancer or if certain abnormalities show up on the ultrasound, your doctor may also do:

  • Hysteroscopy (looking inside your uterus with a viewing tube)

  • Biopsy—taking a sample of tissue from the lining of your uterus and looking at it under a microscope

How do doctors treat abnormal uterine bleeding?

First, doctors usually:

If medicine doesn’t stop your abnormal uterine bleeding, doctors may do a procedure such as:

  • Scraping the lining of your uterus to remove tissue—this is called a D and C (dilation and curettage)

  • Removing the lining of your uterus by freezing or burning it—this is called endometrial ablation

If the above treatments don’t stop your bleeding or if the tests show cancer, doctors may do surgery to remove your uterus. The surgery is called a hysterectomy.

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