What is the ruling for a woman whose bleeding exceeds 15 days, who cannot distinguish menstrual blood from istihadah and does not remember her previous menstrual habit?

Summary

Such a woman is known as a mutahayyirah mutlaqah: she has had menstruation and purity before, but does not remember the number or timing of her habitual days and cannot distinguish the characteristics of the blood. According to the preferred view in the Shafi'i school, she must observe precaution in worship, being treated as menstruating in some matters and as pure in others. She must perform obligatory prayers and fast in Ramadan, but intercourse, touching or carrying the mushaf, and reciting the Quran outside prayer are prohibited. She must perform ritual bathing for each obligatory prayer, though it is permissible to follow the second view that treats her like a first-time bleeder, especially when the burden is heavy, while the preferred view is encouraged as the more cautious approach.

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