عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا قَالَتْ: اعْتَكَفَ مَعَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ امْرَأَةٌ مِنْ أَزْوَاجِهِ مُسْتَحَاضَةٌ فَكَانَتْ تَرَى الصُّفْرَةَ وَالْحُمْرَةَ، فَرُبَّمَا وَضَعْنَا الطَّسْتَ تَحْتَهَا وَهِيَ تُصَلِّي
Sayyida Aisha (may Allah be pleased with her) narrates that one of the wives of the Messenger of Allah (peace and blessings be upon him) observed i'tikaf with the Messenger of Allah (peace and blessings be upon him), even though she was experiencing istihada (non-menstrual bleeding). She would have yellowish and reddish blood, and sometimes we would place a basin beneath her while she was performing prayer.