More than 7 days
If the menstrual flow lasts for more than 7 days, it might be considered heavy bleeding. It can be called a heavy bleed both in terms of the time for which it might continue or the quantity of blood lost. The condition has a clinical name and is called menorrhagia. Heavy bleeding must not be left unchecked or unattended for long as it can lead to blood loss and can cause significant discomfort to the person affected.