It was narrated from ‘Aishah that the daughter of Abu Hubaish said: “Messenger of Allah صلی اللہ علیہ وآلہ وسلم, I do not become pure, so should I stop praying?” He said: “No, that is a vein.” — (One of the narrators) Khalid said, in what I read from him — “and it is not menstruation, so when your period comes, stop praying, and when it goes, wash the blood from yourself and pray.” (Sahih)