How is Very Heavy Flow or Menorrhagia defined?
Officially, flow of more than 80 ml (or 16 soaked sanitary products) per menstrual period is considered menorrhagia. Most women bleeding this heavily will have a low blood count (anemia) or evidence of iron deficiency (1). In practice only about a third of women have anemia, so the definition of heavy flow can be adjusted to be more like nine to 12 soaked regular-sized sanitary products in a period (2).
