"If it is menstrual blood then it is blood that is black and recognizable, so stop prying, and if it is other than that then perform Wudu', for it is just a vein."  

لَهَا رَسُولُ اللَّهِ ﷺ إِذَا كَانَ دَمُ الْحَيْضِ فَإِنَّهُ دَمٌ أَسْوَدُ يُعْرَفُ فَأَمْسِكِي عَنِ الصَّلاَةِ وَإِذَا كَانَ الآخَرُ فَتَوَضَّئِي فَإِنَّمَا هُوَ عِرْقٌ قَالَ مُحَمَّدُ بْنُ الْمُثَنَّى حَدَّثَنَا ابْنُ أَبِي عَدِيٍّ هَذَا مِنْ كِتَابِهِ  

"Menstrual blood is blood that is black and recognizable, so if it is like that, then stop praying, and if it is otherwise, then perform Wudu' and pray." Abu 'Abdur-Rahman said: Others reported this Hadith, and none of them mentioned what Ibn 'Adi mentioned, and Allah knows best.  

أَنَّ فَاطِمَةَ بِنْتَ أَبِي حُبَيْشٍ كَانَتْ تُسْتَحَاضُ فَقَالَ لَهَا رَسُولُ اللَّهِ ﷺ إِنَّ دَمَ الْحَيْضِ دَمٌ أَسْوَدُ يُعْرَفُ فَإِذَا كَانَ ذَلِكِ فَأَمْسِكِي عَنِ الصَّلاَةِ فَإِذَا كَانَ الآخَرُ فَتَوَضَّئِي وَصَلِّي قَالَ أَبُو عَبْدِ الرَّحْمَنِ قَدْ رَوَى هَذَا الْحَدِيثَ غَيْرُ وَاحِدٍ وَلَمْ يَذْكُرْ أَحَدٌ مِنْهُمْ مَا ذَكَرَ ابْنُ أَبِي عَدِيٍّ وَاللَّهُ تَعَالَى أَعْلَمُ  

"Fatimah bint Abi Hubaish suffered from Istihadah and she asked the Prophet ﷺ: 'O Messenger of Allah, I suffer from Istihadah and I do not become pure; should I stop praying?' The Messenger of Allah ﷺ said: 'That is a vein and is not menstruation. When your period comes, stop praying, and when it goes wash the traces of blood from yourself and do Wudu'. That is a vein and is not menstruation.'" It was said to him (one of the narrators): "What about Ghusl?" He said: "No one is in doubt about that."  

قَالَتِ اسْتُحِيضَتْ فَاطِمَةُ بِنْتُ أَبِي حُبَيْشٍ فَسَأَلَتِ النَّبِيَّ ﷺ فَقَالَتْ يَا رَسُولَ اللَّهِ إِنِّي أُسْتَحَاضُ فَلاَ أَطْهُرُ أَفَأَدَعُ الصَّلاَةَ قَالَ رَسُولُ اللَّهِ ﷺ إِنَّمَا ذَلِكِ عِرْقٌ وَلَيْسَتْ بِالْحِيضَةِ فَإِذَا أَقْبَلَتِ الْحِيضَةُ فَدَعِي الصَّلاَةَ وَإِذَا أَدْبَرَتْ فَاغْسِلِي عَنْكِ الدَّمَ وَتَوَضَّئِي وَصَلِّي فَإِنَّمَا ذَلِكِ عِرْقٌ وَلَيْسَتْ بِالْحَيْضَةِ قِيلَ لَهُ فَالْغُسْلُ قَالَ وَذَلِكَ لاَ يَشُكُّ فِيهِ أَحَدٌ قَالَ أَبُو عَبْدِ الرَّحْمَنِ قَدْ رَوَى هَذَا الْحَدِيثَ غَيْرُ وَاحِدٍ عَنْ هِشَامِ بْنِ عُرْوَةَ وَلَمْ يَذْكُرْ فِيهِ وَتَوَضَّئِي غَيْرُ حَمَّادٍ وَاللَّهُ تَعَالَى أَعْلَمُ  

"Fatimah bint Abi Hubaish said to the Messenger of Allah ﷺ: 'O Messenger of Allah ﷺ, I do not become pure. Should I stop praying?' The Messenger of Allah ﷺ said: 'That is a vein and is not menstruation. When your period comes, stop praying, and when it has passed, then wash the blood from yourself and pray.'"  

أَنَّ فَاطِمَةَ بِنْتَ أَبِي حُبَيْشٍ أَتَتْ رَسُولَ اللَّهِ ﷺ فَقَالَتْ يَا رَسُولَ اللَّهِ إِنِّي أُسْتَحَاضُ فَلاَ أَطْهُرُ فَقَالَ رَسُولُ اللَّهِ ﷺ إِنَّمَا ذَلِكِ عِرْقٌ وَلَيْسَتْ بِالْحِيضَةِ فَإِذَا أَقْبَلَتِ الْحِيضَةُ فَأَمْسِكِي عَنِ الصَّلاَةِ وَإِذَا أَدْبَرَتْ فَاغْسِلِي عَنْكِ الدَّمَ وَصَلِّي  

Fatimah bint Abi Hubaish said to the Messenger of Allah ﷺ: "O Messenger of Allah ﷺ, I do not become pure. Should I stop praying?" The Messenger of Allah ﷺ said: "That is a vein and is not menstruation. When your period comes, stop praying, and when the same amount of time as your regular period has passed, then wash the blood from yourself and pray."  

قَالَتْ فَاطِمَةُ بِنْتُ أَبِي حُبَيْشٍ لِرَسُولِ اللَّهِ ﷺ لاَ أَطْهُرُ أَفَأَدَعُ الصَّلاَةَ فَقَالَ رَسُولُ اللَّهِ ﷺ إِنَّمَا ذَلِكِ عِرْقٌ وَلَيْسَتْ بِالْحِيضَةِ فَإِذَا أَقْبَلَتِ الْحِيضَةُ فَدَعِي الصَّلاَةَ وَإِذَا ذَهَبَ قَدْرُهَا فَاغْسِلِي عَنْكِ الدَّمَ وَصَلِّي  

"O Messenger of Allah, I do not become pure, so should I stop praying? He said: "no, that is a vein." - (One of the narrators) Khalid said, in what I read from him - "and it is not menstruation, so when your period comes, stop praying, and when it goes, wash the blood from yourself and pray."  

يَا رَسُولَ اللَّهِ إِنِّي لاَ أَطْهُرُ أَفَأَتْرُكُ الصَّلاَةَ قَالَ لاَ إِنَّمَا هُوَ عِرْقٌ قَالَ خَالِدٌ وَفِيمَا قَرَأْتُ عَلَيْهِ وَلَيْسَتْ بِالْحِيضَةِ فَإِذَا أَقْبَلَتِ الْحِيضَةُ فَدَعِي الصَّلاَةَ وَإِذَا أَدْبَرَتْ فَاغْسِلِي عَنْكِ الدَّمَ ثُمَّ صَلِّي