Abdul Aziz ibn Yahya narrated to us, Muhammad ibn Salamah narrated to me, from Muhammad ibn Ishaq, from Abd al-Rahman ibn al-Qasim, from his father, from Aishah, that Sahlah bint Suhayl experienced prolonged bleeding (Istihadah). She came to the Prophet, may Allah bless him and grant him peace, and he commanded her to perform ghusl (bath) for every prayer. When that became too difficult for her, he commanded her to combine the Dhuhr and Asr prayers with one ghusl, the Maghrib and Isha prayers with one ghusl, and to perform ghusl for Fajr.
Abu Dawud said: Ibn Uyainah narrated it from Abd al-Rahman ibn al-Qasim, from his father, that a woman experienced prolonged bleeding and asked the Messenger of Allah, may Allah bless him and grant him peace, and he commanded her with something similar.