It is narrated from Sayyidah Aishah (may Allah be pleased with her) that she said: I would drink from the cup while I was menstruating, and then the Prophet (peace and blessings be upon him) would put his mouth on the place from which I had drunk; and I would take a bone (with meat on it) and tear at it with my teeth, and he (peace and blessings be upon him) would put his mouth on the place where I had torn at it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحيض / 1496