(3) باب جَوَازِ غَسلِ الْحَائِضِ رَأْسَ زَوْجِهَا وَتَرْجِيلِهِ وَطَهَارَةِ سُؤْرِهَا وَالاِتِّكَاءِ فِي حِجْرِهَا وَقِرَاءَةِ الْقُرْآنِ فِيهِ
It is reported from 'A'isha that she observed:
When the Messenger of Allah (ﷺ) was in I'tikaf, he inclined his head towards me and I combedhis hair, and he did not enter the house but for the natural calls (for relieving himself).
Reference: Sahih Muslim 297 a
In-book reference: Book 3, Hadith 6
USC-MSA web (English) reference(deprecated numbering scheme): Book 3, Hadith 582