Sayyida Aisha (may Allah be pleased with her) narrates that Fatima bint Abu Hubaysh (may Allah be pleased with her) came to the Messenger of Allah (peace and blessings be upon him) and said: I suffer from Istihada (non-menstrual bleeding), due to which I cannot remain pure. Should I stop praying? He said: This is not menstruation, rather it is blood from a vein. When menstruation comes, leave the prayer. When the menstruation ends, wash off the blood and perform the prayer.
Hadith Referenceالمنتقى ابن الجارود / كتاب الطهارة / 112