is to be regarded as menstrual blood, and what is to be treated as istiḥāḍah, for which she does not abandon fasting or prayer, because a woman in istiḥāḍah is governed by the rulings of those who are ritually pure.

Accordingly, the mustaḥāḍah faces three possible situations:

1. She had a known, regular cycle before the onset of istiḥāḍah—for example, she used to menstruate five or eight days at the beginning or in the middle of the month, and she knows both its duration and its timing. In this case she refrains from prayer and fasting for the length of her habit, and all the rulings of menstruation apply to her. Once her usual period ends, she performs ghusl, resumes the prayer, and regards any remaining blood as istiḥāḍah. The proof is the Prophet’s ﷺ directive to Umm Ḥabībah: “Stay away for the length of time that your menses used to keep you back; then perform ghusl and pray” (1), and his ﷺ words to Fāṭimah bint Abī Ḥubaysh: “That is only a vein; it is not menstruation. When your normal period arrives, leave off the prayer” (2).

2. She has no established habit, but her blood is distinguishable: part of it bears the characteristics of menses—being dark, thick, or having an odor—while the rest lacks those marks, being red, thin, and without odor. In this situation she regards the blood that carries the characteristics of menstruation