Sahih Bukhari – Hadith No : 379

Narrates `Abdullah bin Shaddad: Maimuna said, “Allah’s Apostle was praying while I was in my menses, sitting beside him and sometimes his clothes would touch me during his prostration.” Maimuna added, “He prayed on a Khumra (a small mat sufficient just for the face and the hands while prostrating during prayers).

Hadith In Arabic Text :

حدثنا مسدد، عن خالد، قال حدثنا سليمان الشيباني، عن عبد الله بن شداد، عن ميمونة، قالت كان رسول الله صلى الله عليه وسلم يصلي وأنا حذاءه وأنا حائض وربما أصابني ثوبه إذا سجد‏.‏ قالت وكان يصلي على الخمرة‏.‏

Chapter : Prayers (Salat) – كتاب الصلاة