Sahih al-Bukhari, Book 6, Hadith 15 (In-Book) ⓘ
Narrated `Aisha: "One of the wives of Allah's Messenger joined him in I`tikaf and she noticed blood and yellowish discharge (from her private parts) and put a dish under her when she prayed."
حَدَّثَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ، عَنْ خَالِدٍ، عَنْ عِكْرِمَةَ، عَنْ عَائِشَةَ، قَالَتِ اعْتَكَفَتْ مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم امْرَأَةٌ مِنْ أَزْوَاجِهِ، فَكَانَتْ تَرَى الدَّمَ وَالصُّفْرَةَ، وَالطَّسْتُ تَحْتَهَا وَهْىَ تُصَلِّي.
also referenced under: Hadith 310 (DarusSalam) & Volume 1, Book 6, Hadith 307 (USC-MSA)