In the hadith of Abu al-Ash'ath it is that his maternal aunt, Fatimah bint Abi Hubaysh (may Allah be pleased with her), had istihadah (irregular bleeding) and remained for a period of time not praying. She came to the Mother of the Believers, Aishah (may Allah be pleased with her), and mentioned it to her. The Prophet (peace and blessings be upon him) came in, and Sayyidah Aishah (may Allah be pleased with her) said: "O Messenger of Allah! Fatimah has mentioned that she has istihadah." The Prophet (peace and blessings be upon him) said: "Tell Fatimah: every month she should refrain from prayer for the number of her menstrual days as they were before this befell her; then she should perform one ritual bath (ghusl), then ablution for every prayer."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحيض / 1661