the Prophet said about the Mustahadah that she should: "Leave the Salat for the days of her period which she menstruates in, then perform Ghusl, and perform Wudu for every Salat, and observe Saum and perform Salat."
عَنِ النَّبِيِّ ﷺ أَنَّهُ قَالَ فِي الْمُسْتَحَاضَةِ تَدَعُ الصَّلاَةَ أَيَّامَ أَقْرَائِهَا الَّتِي كَانَتْ تَحِيضُ فِيهَا ثُمَّ تَغْتَسِلُ وَتَتَوَضَّأُ عِنْدَ كُلِّ صَلاَةٍ وَتَصُومُ وَتُصَلِّي