Yahya related to me from Malik from Abd ar-Rahman ibn al-Qasim from his father from Asma bint Umays that she gave birth to Muhammad ibn Abi Bakr at al-Bayda. Abu Bakr mentioned this to the Messenger of Allah ﷺ and he said, "Tell her to do ghusl and then enter ihram."
أَنَّهَا وَلَدَتْ مُحَمَّدَ بْنَ أَبِي بَكْرٍ بِالْبَيْدَاءِ فَذَكَرَ ذَلِكَ أَبُو بَكْرٍ لِرَسُولِ اللَّهِ ﷺ فَقَالَ مُرْهَا فَلْتَغْتَسِلْ ثُمَّ لِتُهِلَّ