and this artery is called al-ʿādhil. Physicians explain istiḥāḍah as a set of disorders that arise and bring about this bleeding, which may at times be severe.

Dr. Muḥammad ʿAlī al-Bār writes: “Istiḥāḍah is blood that issues from the uterus, the cervix, or the vagina as a consequence of a benign or malignant growth, inflammation of the cervix or vagina, or other diseases of this system. It can also be triggered by the use of medication, and this last cause is perhaps the most common, for certain drugs inhibit coagulation. These are the principal causes of istiḥāḍah.”

3 - A woman afflicted with istiḥāḍah who does not know her original menstrual habit and has no reliable way to distinguish menstrual blood from istiḥāḍah blood should regard herself as menstruating by abandoning prayer, fasting, and the like for the average duration of women’s periods—six or seven days. During those days she considers herself menstruant, and the rulings of menstruation apply to her.

4 - Once those six or seven days have ended, she performs the ghusl for menstruation, even if the istiḥāḍah continues, then she prays for twenty-four or twenty-three days and fasts. Those obligatory prayers and fasts suffice for her, for she is now deemed ritually pure from menstruation.

5 - She follows this procedure every month, because the prevailing pattern among women is that the cycle of menstruation and purity together is thirty days: six or seven of them menstruation and the rest purity. This is the closest estimate for her, and in most cases the month corresponds to a lunar month.

6 - The blood of istiḥāḍah does not bar a woman from prayer or other acts of worship that require ritual purity.

7 - Menstrual blood, however, does prevent prayer and the like of acts whose validity is conditioned upon freedom from menstruation, and prayers missed during menses are not made up.

8 - Blood is impure and must be washed away, by the unanimous agreement of the scholars.