Heavy blood loss

It’s difficult to provide an exact definition of how much blood loss during a period is ‘heavy’ as every woman is different and has a different ‘normal’. As a rough guide, if you have to change your protection every one to two hours, then you have heavy blood loss and may have menorrhagia. Other indications could be if you experience flooding through to your clothes or bedding, or if you need to use tampons and sanitary towels together to prevent leaking.

Normally, you lose about 4-12 teaspoons (20-60ml) of menstrual blood, menstruate every 24-31 days, and your period lasts 4-7 days[1]NHS Choices. Irregular periods. Last accessed August 2017 , [2]Center for Disease Control. Menorrhagia. Last accessed Aug 2017 (Normally a soaked regular tampon holds approximately 5ml of blood and super or maxi pads hold about 10ml). If your period lasts longer than 7 days, you lose in excess of 12 teaspoons (60ml+) of blood, and your cycle is shorter than 21 days, then you have heavy periods[3]NHS Choices. Heavy Periods. Last accessed 14 Aug 2017 .


For 60% of women with this condition, no clear cause can be identified, but a change in hormone levels is a common cause. Other causes include:


Heavy blood loss can cause various unpleasant physical complaints, for example, iron deficiency or anaemia, fatigue, and menstrual pain. It can impede your social life considerably.

If your heavy periods are dictating your life, do not suffer in silence. Contact your GP. Read about how to prepare for your GP appointment here.

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