Musnad Ahmad 1153:1576

Waki’ narrated to us, Sufyan and Mis’ar narrated to us, from al-Miqdam ibn Shurayh, from his father, from ‘Aishah, who said: "I used to drink while I was menstruating, then I would hand it to the Prophet, peace and blessings of Allah be upon him, and he would place his mouth upon the place where my mouth had been. And I would gnaw on a piece of meat while I was menstruating, then I would hand it to him, and he would place his mouth upon the place where my mouth had been."