Sunan an-Nasa'i 3553
سنن النسائي#3553Da'ifIt was narrated from 'Amr bin Az-Zubair that Fatimah bint Abi Hubaish told him that she came to the Messenger of Allah and complained to him about (continual) bleeding. The Messenger of Allah said to her:"That is a vein. Look and when your period comes, do not pray, and when your period ends, then purify yourself and pray during the time between one period and the next
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiDaif
In-book reference: 27:167