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Woman researching heavy periods on laptop

What is HMB?


Heavy menstrual bleeding (HMB), also known as menorrhagia, can be a serious and debilitating medical condition. It is defined by the impact it has on a woman’s physical, social and emotional quality of life, for example, if your monthly period limits your normal daily activities, or affects your role at work.

About Heavy menstrual bleeding

A good indication that blood loss is excessive is if you experience any of the following:

pads or tampons

You are using an unusually high number of pads or tampons, for example, if there is enough blood to soak a pad or tampon every hour for several consecutive hours.

heavy bleeding

You are experiencing flooding (heavy bleeding) through to your clothes.

tampons and pads

You need to use double protection, i.e. tampons and pads together.

night time bleeding

You are experiencing night time bleeding that requires you to get up to change pads or tampons, use extra protection at night and/or change your bed sheets.

One in three women have heavy menstrual bleeding at some point in their lives.


Feel HMB impacts their ability to perform sport and fitness activities.


Feel that their heaviest bleeding days affect their performance at work.


Do not tend to participate in social activities when their period is heavy.

However, in almost 50% of women with HMB, no underlying causes is found, this means that many women can be treated by their GP.

Woman consulting GP
Woman considering causes of heavy menstrual bleeding


For the majority of women with HMB there is no obvious cause. However some conditions such as endometriosis and fibroids have been linked to HMB.


Learn more

PP-UN-WHC-GB-0047 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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