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Uterine Bleeding

Abnormal uterine bleeding can occur for a number of reasons, including problems with ovulation, a hormonal imbalance or abnormalities of the vagina, cervix or uterus.

Abnormal bleeding may be:

  • Prolonged — longer than a woman's normal menstrual period
  • Frequent — less than 21 days from the first day of one bleeding episode to the first day of the next
  • Heavier than usual — requiring more than a pad every hour during the heaviest time

Common reasons for abnormal uterine bleeding include:

  • Anovulation — Lack of normal menstrual bleeding due to problems with hormone secretion by the ovary. A doctor can usually diagnose anovulation by taking a medical history and performing a physical examination. Blood tests for hormone levels are sometimes helpful. Treatment usually involves medication to correct the hormone imbalance.
  • Abnormalities of the vagina and cervix — Infections or other conditions of the vagina and cervix can cause bleeding, though the bleeding is usually light and may be associated with intercourse. Post-menopausal women may have thinning of the vaginal walls, which can lead to light bleeding. Abnormalities of the cervix, including cervical cancer, also can cause bleeding. These conditions can be diagnosed by physical examination and office tests.
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A medical history and gynecologic examination are useful in identifying the cause of abnormal uterine bleeding. Other tests may include endometrial biopsy, in which a small amount of tissue is removed from the uterine cavity to assist in making a diagnosis; hormone tests; or ultrasound. Hysteroscopy, a procedure during which a tiny "telescope" is placed into the uterine cavity to examine the cavity, can also be helpful.

Abnormal bleeding may be treated with hormones such as oral contraceptive pills. Sometimes hysteroscopy is required to remove a polyp or small fibroid.

Heavy bleeding often can be decreased or stopped by endometrial ablation, a procedure in which the uterine lining is removed or destroyed. Some women choose hysterectomy, or removal of the uterus, as the most definitive way of ending abnormal bleeding once and for all.

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Reviewed by health care specialists at UCSF Medical Center.