Bulugh al-Maram, Book 1, Hadith 79 (In-Book)

Narrated ‘Aisha (rad): Fatima bint Abu Hubaish came to the Prophet and said, “O Messenger of Allah, I am a woman whose blood keeps flowing (even after the menstruation). I am never purified; should I, therefore, stop praying?” He (the Prophet) said: “No, for that is only a vein, and is not menstruation. So when the menstruation comes, abstain from prayers, and when it ends wash the blood from yourself and then pray”. [Agreed upon].

وَعَنْ عَائِشَةَ رَضِيَ اَللَّهُ عَنْهَا قَالَتْ: { جَاءَتْ فَاطِمَةُ بِنْتُ أَبِي حُبَيْشٍ إِلَى اَلنَّبِيِّ ‏- صلى الله عليه وسلم ‏-فَقَالَتْ: يَا رَسُولَ اَللَّهِ! إِنِّي اِمْرَأَةٌ أُسْتَحَاضُ فَلَا أَطْهُرُ, أَفَأَدَعُ اَلصَّلَاةَ? قَالَ: "لَا.‏ إِنَّمَا ذَلِكَ عِرْقٌ, وَلَيْسَ بِحَيْضٍ, فَإِذَا أَقْبَلَتْ حَيْضَتُكِ فَدَعِي اَلصَّلَاةَ, وَإِذَا أَدْبَرَتْ فَاغْسِلِي عَنْكِ اَلدَّمَ, ثُمَّ صَلِّي } مُتَّفَقٌ عَلَيْه ِ (85)‏.‏ ‏1 ‏- صحيح.‏ رواه البخاري (328)‏، ومسلم (333)‏.‏

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also referenced under: Book 1, Hadith 73 (English)