It is narrated from Umm al-Mu'mineen Sayyidah Aisha (may Allah be pleased with her) that when the Messenger of Allah (peace and blessings be upon him) would observe i'tikaf in the mosque, he would extend his blessed head towards me (into the chamber) and I would wash it, even though I was in the state of menstruation.
Hadith Referenceالسنن المأثورة / باب ما جاء في الاعتكاف / 350
Hadith Takhrijصحیح بخاری، الحیض ، باب غسل الحائض رأس زوجہا و ترجیلہ، رقم : 295، 296