What is the ruling on prayer and fasting during the days when there is a discharge of a reddish fluid, or drops of blood, or intermittent bleeding after the cessation of menstruation due to birth control pills, and is this considered istihadah (irregular vaginal bleeding) or hayd (menstruation), especially given the presence of pain similar to menstrual pain?

If the brown discharge is blood and it continues for twenty-four hours or more after a long period of purity, then it is menstruation (hayd), and the woman's actions of refraining from prayer and fasting are correct.

However, if the blood or yellowish-brown discharge (kudrah) returns in less than fifteen days from the period of purity, it is not considered a separate menstruation. And if the total days of the first and second blood and yellowish-brown discharge, and the purity period in between, exceed fifteen days, then this is irregular bleeding (istihada), and the woman with irregular bleeding prays and fasts.

The woman with irregular bleeding should return to distinguishing between menstrual blood and other blood. If she can distinguish by color, smell, or strength, then the period of distinction is considered menstruation. If she cannot distinguish, she should refer to her usual cycle, observing her accustomed days as menstruation and considering the rest as purity. The Hanbalis prefer referring to the customary cycle first.