Skip to main content

Dysfunctional uterine bleeding

Medically reviewed by Last updated on Feb 15, 2024.

What is dysfunctional uterine bleeding?

Harvard Health Publishing

Dysfunctional uterine bleeding, also called anovulatory bleeding, is any bleeding from the vagina that varies from a woman's normal menstrual cycle. The normal cycle is triggered by signals from hormones. Dysfunctional uterine bleeding occurs when the cycle's hormonal signals get thrown off. This can include alternating periods that are heavy and light, spotting or unpredictable shorter and longer cycles.

Regular monthly menstrual cycles flush out the endometrial lining, which is the blood-enriched layer of tissue that grows inside the uterus every month in anticipation of a possible pregnancy. If ovulation does not occur, periods can be delayed, which allows the lining to grow thicker. For this reason, delayed periods are often heavy ones.

Lighter periods, or spotting between periods, may represent an endometrial lining that is unstable and leaking, either because hormonal levels don't adequately support it or because the lining may be too thick.

Other factors that can change bleeding patterns include:

Symptoms of dysfunctional uterine bleeding

Irregular bleeding can come at different times from month to month and last for different lengths of time. The amount of blood flow may vary from light to extremely heavy with large clots. In some people, the bleeding may be associated with uterine cramps.

Diagnosing dysfunctional uterine bleeding

Your doctor will ask about your medical history and about symptoms that might suggest a cause for the irregular bleeding or other hormonal abnormalities. The doctor may do various tests to check for these causes of abnormal bleeding patterns:

If you have heavy bleeding, your doctor will check iron levels in your blood to see if you are anemic.

Expected duration of dysfunctional uterine bleeding

Most women have a period that is irregular in timing or in the amount of bleeding at some point during their menstrual years, most often because of a cycle without a normal ovulation. Normal periods may resume as early as the next period or might take a few months to become regular again. Some women become regular only with the help of treatments, such as birth control pills. If irregular periods signal the beginning of menopause, the last period may not occur for a few months or a few years.

Treatment options

The following list of medications are related to or used in the treatment of this condition.

View more treatment options

Preventing dysfunctional uterine bleeding

There is no way to prevent dysfunctional uterine bleeding. See a doctor promptly if you continue to have irregular periods. Early diagnosis and treatment can help to make your periods regular again, which is important for your overall health.

Treating dysfunctional uterine bleeding

If the cause of dysfunctional uterine bleeding is another medical condition, treating that condition should restore normal cycles. Otherwise, treatment is based on the cause, the amount of bleeding and the woman's reproductive goals (whether she wants to have children or not).

Birth control pills, which combine the hormones estrogen and progesterone, can regulate and decrease the amount of bleeding. Your doctor may recommend that you take monthly pills containing progesterone only. Women seeking to become pregnant may be treated with medications to help their ovaries ovulate more regularly.

Heavy bleeding can be stopped with higher doses of hormone pills — either estrogen or progesterone. When bleeding is more severe, hospitalization may be necessary. If hormonal therapy does not work, a surgical D and C (dilation and curettage) can stop severe cases of bleeding. During this procedure, the tissue lining of the uterus is removed, allowing a healthier lining to take its place.

If an endometrial biopsy reveals endometrial hyperplasia, which is a thicker and abnormal looking lining, closer monitoring with treatment may be required, especially in older women and postmenopausal women on hormone replacement therapy. Endometrial hyperplasia increases a woman's risk of developing endometrial cancer.

When to call a professional

Call your doctor right away for an evaluation if you are having fevers, abdominal pain or heavy bleeding with dizziness or fainting.

If your periods are irregular over a few months, make an appointment to see your doctor. Be prepared to tell your doctor the dates of your last few periods.


There are many effective treatments to help regulate periods and control irregular bleeding. If you have irregular periods and are having difficulty becoming pregnant, you can take drugs that stimulate ovulation. Having irregular periods, however, does not mean you are infertile. You still need to use protection against pregnancy when you are sexually active.

Additional info

American College of Obstetricians and Gynecologists

Learn more about Dysfunctional uterine bleeding

Treatment options

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.