أَخْبَرَنَا يَحْيَى بْنُ حَبِيبِ بْنِ عَرَبِيٍّ، عَنْ حَمَّادٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، قَالَتِ اسْتُحِيضَتْ فَاطِمَةُ بِنْتُ أَبِي حُبَيْشٍ فَسَأَلَتِ النَّبِيَّ صلى الله عليه وسلم فَقَالَتْ يَا رَسُولَ اللَّهِ إِنِّي أُسْتَحَاضُ فَلاَ أَطْهُرُ أَفَأَدَعُ الصَّلاَةَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ 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 ‏.‏

It was narrated that 'Aishah said: "Fatimah bint Abi Hubaish suffered from Istihadah and she asked the Prophet (PBUH): 'O Messenger of Allah, I suffer from Istihadah and I do not become pure; should I stop praying?' The Messenger of Allah (PBUH) 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." Translation Not Available

Book Ref: Sunan An Nisai Book 3 Hadith 364
Web Ref:  Sunan An Nisai Vol 1 Book 3 Hadith 364