Sahih al-Bukhari 309
صحيح البخاري#309SahihNarrated `Aisha:Once one of the wives of the Prophet (ﷺ) did I`tikaf along with him and she was getting bleeding in between her periods. She used to see the blood (from her private parts) and she would perhaps put a dish under her for the blood. (The sub-narrator `Ikrima added, `Aisha once saw the liquid of safflower and said, "It looks like what so and so used to have)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 6:14