عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ قَالَ: ((لَا تُقْبَلُ صَلَاةُ حَائِضٍ إِلَّا بِخِمَارٍ))
It is narrated from Sayyidah Aisha (may Allah be pleased with her) that the Noble Prophet (peace and blessings be upon him) said: The prayer of an adult woman is not accepted without a head covering.