What is heavy menstrual bleeding?

The medical definition of heavy periods, also known as menorrhagia, can be defined as losing more than 80mL of blood (approximately 5-6 tablespoons) during each cycle. But in more practical terms, heavy periods can be defined by their impact on your physical, emotional, and social quality of life.

You may be considered to have abnormally heavy periods if you:

Pass blood clots during your period that are larger than a 50 cent coin

Have to change your pad or tampon every one to two hours, including overnight

Are unable to leave the house on the heaviest day of your period

Find it difficult to manage your daily tasks due to your period

Have episodes of flooding, where blood spills through to your underwear or clothing

Have menstrual bleeding lasting more than eight days

Complications of heavy menstrual bleeding

There are several gynaecological conditions that include heavy periods as a symptom. These conditions can come with their own complications, separate to the heavy periods. However, the heavy menstrual bleeding itself can cause iron-deficiency anaemia through excessive blood loss every month. Having low iron can result in you feeling constantly fatigued, dizzy, and short of breath.