"I divorced my wife when she was menstruating. 'Umar went to the Prophet and told him about that. The Prophet said: 'Tell him to take her back, then when she becomes pure, if he wants to, let him divorce her.'" I said to Ibn 'Umar: "Did that count as one divorce?" He said: "Why not? What do you think if some becomes helpless and behaves foolishly." (Using translation from Nasāʾī 3555)  

طَلَّقْتُ امْرَأَتِي وَهِيَ حَائِضٌ فَأَتَى النَّبِيَّ ﷺ عُمَرُ فَذَكَرَ لَهُ ذَلِكَ فَقَالَ النَّبِيُّ ﷺ «فَلْيُرَاجِعْهَا فَإِذَا طَهُرَتْ يَعْنِي فَإِنْ شَاءَ فَلْيُطَلِّقْهَا » قُلْتُ لِابْنِ عُمَرَ فَاحْتَسِبْ بِهَا قَالَ مَا يَمْنَعُهُ أَرَأَيْتَ إِنْ عَجَزَ وَاسْتَحْمَقَ  

[Machine] To return to her until she menstruates another cycle. Then, if she becomes pure, he can divorce her if he wishes, or he can keep her if he wishes. For it is the divorce that God has commanded. Allah Almighty says, "Then, when they have reached their term, retain them in kindness or release them in kindness." [Quran 65:1]  

أَنْ يُرَاجِعَهَا حَتَّى تَحِيضَ حَيْضَةً أُخْرَى فَإِذَا طَهُرَتْ فَإِنْ شَاءَ طَلَّقَهَا وَإِنْ شَاءَ أَمْسَكَهَا فَإِنَّهُ الطَّلَاقٌ الَّذِي أَمَرَ اللهُ بِهِ قَالَ تَعَالَى {فَطَلِّقُوهُنَّ لِعِدَّتِهِنَّ} [الطلاق 1]  

"If it is the first or second divorce, the Messenger of Allah would tell him to take her back and keep her until she has menstruated again and purified herself, then divorce her before having intercourse with her. But if it was three simultaneous divorces, then you have disobeyed Allah with regard to the way in which divorce should be conducted and your wife has become irrevocably divorced." (Using translation from Nasāʾī 3557)  

عَنِ رَجُلٍ طَلَّقَ امْرَأَتَهُ وَهِيَ حَائِضٌ فَيَقُولُ أَمَّا إِنْ يُطَلِّقَهَا وَاحِدَةً أَوِ اثْنَتَيْنِ فَإِنَّ رَسُولَ اللهِ ﷺ «أَمَرَهُ أَنْ يُرَاجِعَهَا ثُمَّ يُمْسِكَهَا حَتَّى تَحِيضَ حَيْضَةً أُخْرَى ثُمَّ تَطْهُرَ ثُمَّ يُطَلِّقَهَا قَبْلَ أَنْ يَمَسَّهَا وَأَمَّا أَنْ يُطَلِّقَهَا ثَلَاثًا فَقَدْ عَصَيْتَ اللهَ فِيمَا أَمَرَكَ بِهِ مِنْ طَلَاقِ امْرَأَتِكَ وَبَانَتْ مِنْكَ امْرَأَتُكَ»  

It was narrated from Ibn 'Umar that he divorced his wife when she was menstruating, and the Messenger of Allah told him to take her back. (Using translation from Nasāʾī 3558)  

أَنَّهُ طَلَّقَ امْرَأَتَهُ وَهِيَ حَائِضٌ «فَأَمَرَهُ رَسُولُ اللهِ ﷺ فَرَاجَعَهَا»  

"Do you know 'Abdullah bin 'Umar?" He said: "Yes." He said: "He divorced his wife when she was menstruating, and 'Umar went to the Prophet and told him about that. He ordered him to take her back until she became pure," and I did not hear him adding anything to that. (Using translation from Nasāʾī 3559)  

فَإِنَّهُ طَلَّقَ امْرَأَتَهُ حَائِضًا فَأَتَى عُمَرُ النَّبِيَّ ﷺ فَأَخْبَرَهُ الْخَبَرَ «فَأَمَرَهُ أَنْ يُرَاجِعَهَا حَتَّى تَطْهُرَ وَلَمْ أَسْمَعْهُ يَزِيدُ عَلَى هَذَا»  

The Prophet ﷺ divorced Hafsah, but he took her back in marriage. (Using translation from Abū Dāʾūd 2283)  

أَنَّ النَّبِيَّ ﷺ كَانَ «طَلَّقَ حَفْصَةَ ثُمَّ رَاجَعَهَا»