any of them to take a ritual bath after one day and one night. Had such an instruction been transmitted, it would have established a minimum duration for menstruation. Yet the hadith scholars agree that the Prophet, may Allah bless him and grant him peace, set no minimum duration for it. The reports transmitted on this matter specify three days, but the scholars versed in his hadith agree that these reports are falsely attributed to him. This is the view of the vast majority of scholars and one of the two positions within Ahmad’s school.

Likewise, if a woman’s established menstrual pattern changes—whether her period becomes longer or shorter, or shifts in timing—the bleeding is menstruation until its persistence establishes that it is non-menstrual bleeding. Her case is like that of a woman menstruating for the first time.

A woman experiencing non-menstrual bleeding should refer first to her established cycle, then to her ability to distinguish between the types of blood, and then to the usual menstrual pattern among women. A Sunnah ruling has been transmitted from the Prophet, may Allah bless him and grant him peace, for each of these three cases. Imam Ahmad adopted all three Sunnah rulings. Some scholars adopted two of the hadiths, while others adopted only one, according to what had reached them and the conclusions of their independent reasoning. May Allah be pleased with them all.

If a pregnant woman sees blood following her familiar pattern, it is menstrual blood, in accordance with the basic presumption.

Postpartum bleeding has neither a minimum nor a maximum duration. Thus, if a woman were to see