Sunan an-Nasa'i, Book 1, Hadith 278 (In-Book) ⓘ

It was narrated that 'Aishah said: "The Prophet would put his head out for me while he was performing I'tikaf [1] and I would wash it, when I was menstruating." [1] Mujawir ("next door") here means while performing I'tikaf.

أَخْبَرَنَا مُحَمَّدُ بْنُ سَلَمَةَ، قَالَ حَدَّثَنَا ابْنُ وَهْبٍ، عَنْ عَمْرِو بْنِ الْحَارِثِ، وَذَكَرَ، آخَرُ عَنْ أَبِي الأَسْوَدِ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ، - رضى الله عنها - قَالَتْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يُخْرِجُ إِلَىَّ رَأْسَهُ مِنَ الْمَسْجِدِ وَهُوَ مُجَاوِرٌ فَأَغْسِلُهُ وَأَنَا حَائِضٌ ‏.‏