It was narrated that 'Aishah said:

"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."

أَخْبَرَنَا يَحْيَى بْنُ حَبِيبِ بْنِ عَرَبِيٍّ، عَنْ حَمَّادٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، 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 .