Chronic abnormal uterine bleeding (CAUB) can be defined in different ways depending on the goals of the defining organization such as FIGO (Federation Internal de Gyenceologie et d'Obstetrique).


Features of chronic abnormal uterine bleeding:

(1) bleeding from the uterine corpus

(2) abnormal in some way (frequency, volume, duration, regularity, impact on quality of life)

(3) present for the majority of the past 6 months


Measuring the volume of blood is difficult and is usually not recommended, at least initially. NICE and other organizations tend to use an blood loss that interferes with the woman's quality of life, and this becomes the target of therapy.


In some circumstances it may be necessary to quantify the amount of blood in some way. The 95th percentile for volume of monthly blood loss is > 80 mL.



"Normal" (5th to 95th percentile, FIGO)

frequency of menses in days

24 to 38 days

regularity of menses cycle to cycle

2 to 20 days

duration of flow

4.5 to 8.0 days


5 to 80 mL


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