[Machine] I asked the Messenger of Allah ﷺ about a woman with irregular menstruation. He said, "She should count the days of her regular menstrual cycle, then perform ghusl (ritual bath) and pray when she becomes pure." Aisha and Umm Salamah also narrated this from Fatimah bint Qays. (Note: The ending of the sentence is unclear in the phrase provided.)
سَأَلْتُ رَسُولَ اللَّهِ ﷺ عَنِ الْمُسْتَحَاضَةِ فَقَالَ «تَقْعُدُ أَيَّامَ أَقْرَائِهَا ثُمَّ تَغْتَسِلُ وَتُصَلِّي عِنْدَ طُهْرِهَا» وَقَدْ رَوَتْ عَائِشَةُ وَأُمُّ سَلَمَةَ عَنْ فَاطِمَةَ بِنْتِ قَيْسٍسكت عنه الذهبي في التلخيص