Fatimah b. Abu Hubaish came to the Apostle ﷺ and said: I am a woman whose blood keeps flowing (even after the menstruation period). I am never purified; should I, therefore, abandon prayer? He (the Holy Prophet) said: Not at all, for that is only a vein, and is not a menstruation, so when menstruation comes, abandon prayer, and when it ends wash the blood from yourself and then pray. (Using translation from Muslim 333a)
جَاءَتْ فَاطِمَةُ بِنْتُ أَبِي حُبَيْشٍ إِلَى النَّبِيِّ ﷺ فَقَالَتْ إِنِّي أُسْتَحَاضُ فَلَا أَطْهُرُ أَفَأَدَعُ الصَّلَاةَ؟ قَالَ «إِنَّمَا ذَلِكَ عِرْقٌ وَلَيْسَتْ بِالْحَيْضَةِ فَإِذَا أَقْبَلَتِ الْحَيْضَةُ فَدَعِي الصَّلَاةَ وَإِذَا أَدْبَرَتْ فَاغْسِلِي عَنْكِ الدَّمَ وَصَلِّي»