Full Sharh — Sahih Muslim 3659
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، وَزُهَيْرُ بْنُ حَرْبٍ، وَابْنُ، نُمَيْرٍ - وَاللَّفْظُ لأَبِي بَكْرٍ - قَالُوا حَدَّثَنَا وَكِيعٌ، عَنْ سُفْيَانَ، عَنْ مُحَمَّدِ بْنِ عَبْدِ الرَّحْمَنِ، مَوْلَى آلِ طَلْحَةَ عَنْ سَالِمٍ، عَنِ ابْنِ عُمَرَ، أَنَّهُ طَلَّقَ امْرَأَتَهُ وَهْىَ حَائِضٌ فَذَكَرَ ذَلِكَ عُمَرُ لِلنَّبِيِّ صلى الله عليه وسلم فَقَالَ " مُرْهُ فَلْيُرَاجِعْهَا ثُمَّ لْيُطَلِّقْهَا طَاهِرًا أَوْ حَامِلاً " .
English Translation
Ibn 'Umar (Allah be pleased with them) reported that he divorced his wife while she was in the state of menses. 'Umar (Allah be pleased with him) made mention of it to Allah's Apostle (ﷺ) and he said:Command him to take her back, then divorce her when she is pure or she is pregnant
Source
Sahih Muslim(صحيح مسلم)
The Book of Divorce
Hadith Number
3659