Is the spotting that precedes menstruation by one day considered menstruation that prevents prayer and intercourse?

If a woman sees blood for a day and a night, then experiences a period of purity (naqāʾ) for a similar duration, and this (intermittency) does not exceed 15 days, scholars differ on the ruling: Malik and Ahmad hold the view that ghusl (definition) (ritual bath) is required with each period of purity. Shafi'i and Abu Hanifa, however, believe that all days of purity and menstruation are considered menstruation.

However, if this intermittency exceeds 15 days, it is unanimously considered istihada (non-menstrual vaginal bleeding), and the rulings for a woman with istihada apply to her. It is important to note that sexual intercourse with a woman whose bleeding is intermittent is forbidden by unanimous consensus until she performs ghusl.