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Woman considering causes of heavy menstrual bleeding

What causes HMB?


In almost 50% of women with HMB, there is no obvious cause. However, some conditions have been linked to HMB, including:

Polycystic ovary

Polycystic ovary syndrome (PCOS)

A common condition caused by an imbalance of reproductive hormones that affects how a woman’s ovaries work.

Pelvic inflammatory

Pelvic inflammatory disease (PID)

An infection in the upper genital tract (the womb, fallopian tubes or ovaries) that can cause pelvic or abdominal pain and bleeding after sex or between periods.



Non-cancerous growths that develop in or around the womb.



When small pieces of the womb lining are found outside the womb, such as in the fallopian tubes, ovaries, bladder or vagina.



An underactive thyroid, where the thyroid gland doesn't produce enough hormones, causing tiredness, weight gain and feelings of depression.


Cervical or endometrial polyps

Non-cancerous growths in the lining of the womb or cervix (neck of the womb).

Blood clotting

Blood clotting

Disorders von Willebrand's disease, haemophillia, platlet function disorders and thrombocytopenia are all examples of disorders that can impact on clotting.

Cancer of the womb

Cancer of the womb

Cancerous growths that develop in or around the womb.

It is important to note that, whether or not a direct cause can be found, HMB is usually a treatable condition and there are choices available for you to discuss with your GP.


Don't suffer in silence, you are not alone.

Woman discussing heavy menstrual bleeding treatment choices with GP
Friends discussing treatment options for heavy menstrual bleeding


Information on the range of options available for HMB…


Learn more

PP-UN-WHC-GB-0048 September 2023


The health information on this site has been reviewed and approved by Bayer by an appropriately qualified medical reviewer. It is intended as general information only. It is not intended to replace a consultation with a healthcare professional, to provide specific medical advice or replace the patient information leaflet provided with your medicine. Treatments discussed here should be initiated under medical supervision. For full information including side effects and eligibility for treatment, please consult your healthcare professional. Always speak to your doctor or nurse for personal medical advice.


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