Fatimah bint Abi Hubaish came to the Messenger of Allah (ﷺ) and said: "I am a woman who suffers from Istihadah and I never become pure. Should I stop praying?" He said: "No, that is a vein, it is not menstruation. When your period comes, stop praying, and when it goes, wash the blood from yourself and pray."
Sunan an-Nasa'i Book 3, Hadith 11
← Previous Hadith "That is a vein, so when your period comes, do not pray, and when your period is over, purify yourself and pray in between one period and the next." Abu 'Abdur-Rahman said: Hisham bin 'Urwah reported this Hadith from 'Urwah, and he did not mention what Al-Mundhir mentioned in it.

Sunan an-Nasa'i Book 3, Hadith 10 Next Hadith → It was narrated from 'Aishah that a woman who suffered from Istihadah at the time of the Messenger of Allah (ﷺ) was told that it was a stubborn vein (i.e., one that would not stop bleeding). She was told to delay Zuhr and bring 'Asr forward, and to perform one Ghusl for both, and to delay Maghrib and bring 'Isha' forward, and to perform one Ghusl for both, and she would perform one Ghusl for Subh.

Sunan an-Nasa'i Book 3, Hadith 12