عَنْ سُلَيْمَانَ بْنِ يَسَارٍ عَنْ أُمِّ سَلَمَةَ زَوْجِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ أَنَّ امْرَأَةً كَانَتْ تُهَرَاقُ الدَّمَ عَلَى عَهْدِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ فَاسْتَفْتَتْ لَهَا أُمُّ سَلَمَةَ زَوْجُ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ فَقَالَ: ((لِتَنْظُرْ عِدَّةَ اللَّيَالِي وَالْأَيَّامِ الَّتِي كَانَتْ تَحِيضُهَا مِنَ الشَّهْرِ، فَإِذَا بَلَغَتْ ذَلِكَ فَلْتَغْتَسِلْ ثُمَّ تَسْتَثْفِرْ بِثَوْبٍ ثُمَّ تُصَلِّي))
The wife of the Messenger, Sayyida Umm Salamah (may Allah be pleased with her), narrates that during the time of the Prophet, a woman began to bleed. So when Sayyida Umm Salamah (may Allah be pleased with her) asked for a ruling for her, the Prophet (peace and blessings be upon him) said: She should observe the number of nights and days in a month during which she used to have her menstruation; when she has completed that duration, she should perform ghusl (ritual bath), tie a cloth around herself, and start performing prayers.