It was narrated from 'Ubadah bin Samit from Rubai' bint Mu'awwidh bin 'Afra'.: He said: "I said to her: 'Tell me your Hadith.' She said: 'I got Khul' from my husband, then I came to 'Uthman and asked him: "What waiting period do I have to observe?" He said: "You do not have to observe any waiting period, unless you had intercourse with him recently, in which case you should stay with him until you have menstruated." In that he was following the ruling of the Messenger of Allah (ﷺ) concerning Maryam Maghaliyyah, who was married to Thabit bin Qais and she got Khul' from him.' "
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا عَلِيُّ بْنُ سَلَمَةَ النَّيْسَابُورِيُّ، حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ بْنِ سَعْدٍ، حَدَّثَنَا أَبِي، عَنِ ابْنِ إِسْحَاقَ، أَخْبَرَنِي عُبَادَةُ بْنُ الْوَلِيدِ بْنِ عُبَادَةَ بْنِ الصَّامِتِ، عَنِ الرُّبَيِّعِ بِنْتِ مُعَوِّذِ ابْنِ عَفْرَاءَ، قَالَ قُلْتُ لَهَا حَدِّثِينِي حَدِيثَكِ، . قَالَتِ اخْتَلَعْتُ مِنْ زَوْجِي ثُمَّ جِئْتُ عُثْمَانَ . فَسَأَلْتُ مَاذَا عَلَىَّ مِنَ الْعِدَّةِ فَقَالَ لاَ عِدَّةَ عَلَيْكِ إِلاَّ أَنْ يَكُونَ حَدِيثَ عَهْدٍ بِكِ فَتَمْكُثِينَ عِنْدَهُ حَتَّى تَحِيضِينَ حَيْضَةً . قَالَتْ وَإِنَّمَا تَبِعَ فِي ذَلِكَ قَضَاءَ رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ فِي مَرْيَمَ الْمَغَالِيَّةِ . وَكَانَتْ تَحْتَ ثَابِتِ بْنِ قَيْسٍ فَاخْتَلَعَتْ مِنْهُ .
sunnah.com