It was narrated from 'Urwah that Fatimah bint Abi Hubaish narrated that she came to the Messenger of Allah ﷺ and complained to him about bleeding. The Messenger of Allah ﷺ said to her:

"That is a vein, so when your period comes, do not pray, and when your period is over, purify yourself and pray in between one period and the next."
This is evidence that Al-Aqra' is menstruation. Abu 'Abdur-Rahman said: Hisham bin 'Urwah reported this Hadith from 'Urwah, and he did not mention what Al-Mundhir mentioned in it.

أَخْبَرَنَا عِيسَى بْنُ حَمَّادٍ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ، عَنْ بُكَيْرِ بْنِ عَبْدِ اللَّهِ، عَنِ الْمُنْذِرِ بْنِ الْمُغِيرَةِ، عَنْ عُرْوَةَ، أَنَّ فَاطِمَةَ بِنْتَ أَبِي حُبَيْشٍ، حَدَّثَتْ أَنَّهَا، أَتَتْ رَسُولَ اللَّهِ ﷺ فَشَكَتْ إِلَيْهِ الدَّمَ فَقَالَ لَهَا رَسُولُ اللَّهِ ﷺ " إِنَّمَا ذَلِكِ عِرْقٌ فَانْظُرِي إِذَا أَتَاكِ قُرْؤُكِ فَلاَ تُصَلِّي فَإِذَا مَرَّ قُرْؤُكِ فَتَطَهَّرِي ثُمَّ صَلِّي مَا بَيْنَ الْقُرْءِ إِلَى الْقُرْءِ " هَذَا الدَّلِيلُ عَلَى أَنَّ الأَقْرَاءَ حِيَضٌ . قَالَ أَبُو عَبْدِ الرَّحْمَنِ وَقَدْ رَوَى هَذَا الْحَدِيثَ هِشَامُ بْنُ عُرْوَةَ عَنْ عُرْوَةَ وَلَمْ يَذْكُرْ فِيهِ مَا ذَكَرَ الْمُنْذِرُ .