What is the prescribed procedure for a woman in Istihada who has a known customary period but lacks visual discernment in her blood flow?

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The prescribed action for a woman in Istihada who has a known period length is to refrain from prayer for the number of days that constituted her previous menstruation, then perform Ghusl and pray. This is supported by the narration concerning Fatima, where the Prophet (peace be upon him) instructed her to cease prayer for the duration of her usual menses, then wash and pray. Similarly, Umm Habiba was instructed to remain abstinent for the duration her menstruation usually lasted before washing and praying. Adiyy ibn Thabit narrated from his father, from his grandfather, that the Prophet (peace be upon him) stated regarding the woman in Istihada: She should leave prayer for the days of her usual periods, then perform Ghusl, fast, pray, and make Wudu for every prayer.