It is not permissible for a menstruating woman or a woman in postpartum bleeding to fast, and it is forbidden for her to fast. She must make up the missed fasts, as stated in Tabyin al-Haqaiq 1: 313, Fath al-Qadir 2: 302, and the Indian Fatawa 1: 195. It was narrated that Mu'adhah asked Aisha, may Allah be pleased with her, saying: "Why does a menstruating woman make up her fasts but not her prayers?" She replied: "Are you a Haruri?" I said: "I am not a Haruri, but I am asking." She said: "We used to experience that, and we were commanded to make up the fasts but not the prayers." This is found in Sahih Muslim 1: 265, Sunan Abu Dawood 1: 118, and Sunan al-Nasa'i 4: 191. The term Haruri is attributed to Harura, a town two miles from Kufa, and those who believe in the ideology of the Khawarij are called Haruri; because the first group of them revolted against Ali in that town, they became known by that name. They are many factions, but one of their agreed-upon principles is to adhere to what the Quran indicates and to reject anything beyond it from Hadith absolutely; therefore, they impose on the menstruating woman the obligation to make up the missed prayers during her menstruation, which is contrary to the consensus of Muslims.