The Book of Menstruation (Kitab Al-Haid)

Muslim :: Book 3 : Hadith 659

'A'isha, the wife of the Apostle (may peace be upon him), said: Umm Habiba b. Jahsh who was the spouse of Abd al- Rahman b. Auf made a complaint to the Messenger of Allah (may peace be upon him) about blood (which flows beyond the menstrual period). He said to her: Remain away (from prayer) equal (to the length of time) that your menstruation holds you back. After this, bathe yourself. And she washed herself before every prayer.

Source materials are from the University of Southern California MSA site
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