Sahih Bukhari
Sahih Bukhari Volume 003, Book 033, Hadith Number 253.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 33. Retiring To a Masjid for Remembrance Of Allah (I'tikaf)
Narated By 'Aisha : One of the wives of Allah's Apostle practiced Itikaf with him while she ad bleeding in between her periods and she would see red (blood) or yellowish traces, and sometimes we put a tray beneath her when she offered the prayer.