How does one pray and fast when experiencing continuous menstrual bleeding for three months, interspersed with a few days of purity, followed by three months of purity interspersed with a few days of bleeding, knowing that the discharged blood is menstrual blood with its characteristics and confirmed by the doctor?

The maximum duration of menstruation is fifteen days and nights. If the blood flow exceeds this period, the woman is considered to be in a state of istihadah (non-menstrual bleeding). Her ruling during these three months, in which the blood does not cease, is that of a woman in istihadah.

If she has a previous habit, for example, menstruating for five days, she should revert to her habit. This period is considered menstruation, and she should perform ghusl (ritual purification) after it. Then, she should perform wudu (ablution) for each prayer after the time for it has begun, pray, and take precautions (to prevent blood from staining).

If she does not have a habit and can distinguish menstrual blood by its known characteristics (such as color, smell, or thickness) from istihadah blood, then what she distinguishes as menstrual blood is indeed menstruation, provided it does not exceed fifteen days nor is less than one day and night. Then she performs ghusl and is considered to be in istihadah.

If she has neither a habit nor a sound discernment, she is considered "mutahayyirah" (perplexed). In this case, she should consider the prevalent habit of women among her family (six or seven days) as menstruation. She should perform ghusl after its conclusion, and then she is considered to be in istihadah for the remainder of the month.

The months in which she does not see blood are considered periods of purity. And the blood she sees for one or two days after more than the minimum period of purity between two menstruations has passed (fifteen days according to the majority of scholars) is menstrual blood.