Musannaf Ibn Abi Shaybah

Hazrat Hamnah bint Jahsh says that she suffered from excessive istihada (non-menstrual bleeding) during the time of the Messenger of Allah, peace and blessings be upon him. She presented herself before the Messenger of Allah, peace and blessings be upon him, and said, "I am afflicted with extremely severe istihada." The Prophet, peace and blessings be upon him, said, "Tie a piece of cotton firmly with cloth." She said, "It is much more than that and keeps flowing." The Prophet, peace and blessings be upon him, said, "Put on a cloth belt and, according to Allah’s knowledge, spend six or seven days each month as menstruation, then perform ghusl (ritual bath), and for twenty-three or twenty-four days, offer prayers and keep fasts. Delay the Zuhr prayer and offer Asr early, and perform one ghusl for both. Then delay Maghrib and offer Isha early, and perform one ghusl for both. Of these two options, this is more preferable to me."