Fatima bint Abi Hubaish asked the Prophet, "I got persistent bleeding (in between the periods) and do not become clean. Shall I give up prayers?" He replied, "No, this is from a blood vessel. Give up the prayers only for the days on which you usually get the menses and then take a bath and offer your prayers."  

أَنَّ فَاطِمَةَ بِنْتَ أَبِي حُبَيْشٍ سَأَلَتِ النَّبِيَّ ﷺ قَالَتْ إِنِّي أُسْتَحَاضُ فَلاَ أَطْهُرُ أَفَأَدَعُ الصَّلاَةَ فَقَالَ لاَ إِنَّ ذَلِكِ عِرْقٌ وَلَكِنْ دَعِي الصَّلاَةَ قَدْرَ الأَيَّامِ الَّتِي كُنْتِ تَحِيضِينَ فِيهَا ثُمَّ اغْتَسِلِي وَصَلِّي  

"A woman asked the Prophet ﷺ: 'I suffer from Istihadah and I never become pure; should I stop praying?' He said: 'No. Stop praying for the number of days and nights that you used to menstruate, then perform Ghusl, wrap a cloth around yourself, and pray.'"  

سَأَلَتِ امْرَأَةٌ النَّبِيَّ ﷺ قَالَتْ إِنِّي أُسْتَحَاضُ فَلاَ أَطْهُرُ أَفَأَدَعُ الصَّلاَةَ قَالَ لاَ وَلَكِنْ دَعِي قَدْرَ تِلْكَ الأَيَّامِ وَاللَّيَالِي الَّتِي كُنْتِ تَحِيضِينَ فِيهَا ثُمَّ اغْتَسِلِي وَاسْتَثْفِرِي وَصَلِّي  

"A woman asked the Prophet: 'I bleed continuously and I do not become pure. Should I give up the prayer?' He said: 'No, but leave off praying for the number of days and nights that used to menstruate.'" (One of the narrators) Abu Bakr (Ibn Abu Shaibah) said in this Hadith: "Estimate the number of days in the month, then take a bath and cover your private part with a cloth and perform prayer."  

سَأَلَتِ امْرَأَةٌ النَّبِيَّ ﷺ قَالَتْ إِنِّي أُسْتَحَاضُ فَلاَ أَطْهُرُ أَفَأَدَعُ الصَّلاَةَ قَالَ لاَ وَلَكِنْ دَعِي قَدْرَ الأَيَّامِ وَاللَّيَالِي الَّتِي كُنْتِ تَحِيضِينَ قَالَ أَبُو بَكْرٍ فِي حَدِيثِهِ وَقَدْرَهُنَّ مِنَ الشَّهْرِ ثُمَّ اغْتَسِلِي وَاسْتَثْفِرِي بِثَوْبٍ وَصَلِّي  

"سألت امرأة النبي ﷺ فقالت: إني أستحاض فلا أطهر، فأدع الصلاة؟ قال: لا، ولكن دعي قدر الأيام التي كنت تحيضين وقدرهن، ثم اغتسلي واستنفري، وصلي".