I conceived ʿAbdullah bin AzZubair at Mecca and went out (of Mecca) while I was about to give birth. I came to Medina and encamped at Quba', and gave birth at Quba'. Then I brought the child to Messenger of Allah ﷺ and placed it (on his lap). He asked for a date, chewed it, and put his saliva in the mouth of the child. So the first thing to enter its stomach was the saliva of Messenger of Allah ﷺ. Then he did its Tahnik with a date, and invoked Allah to bless him. It was the first child born in the Islamic era, therefore they (Muslims) were very happy with its birth, for it had been said to them that the Jews had bewitched them, and so they would not produce any offspring.  

عَنْ أَسْمَاءَ بِنْتِ أَبِي بَكْرٍ ؓ أَنَّهَا حَمَلَتْ بِعَبْدِ اللَّهِ بْنِ الزُّبَيْرِ بِمَكَّةَ قَالَتْ فَخَرَجْتُ وَأَنَا مُتِمٌّ فَأَتَيْتُ الْمَدِينَةَ فَنَزَلْتُ قُبَاءً فَوَلَدْتُ بِقُبَاءٍ ثُمَّ أَتَيْتُ بِهِ رَسُولَ اللَّهِ ﷺ فَوَضَعْتُهُ فِي حَجْرِهِ ثُمَّ دَعَا بِتَمْرَةٍ فَمَضَغَهَا ثُمَّ تَفَلَ فِي فِيهِ فَكَانَ أَوَّلَ شَىْءٍ دَخَلَ جَوْفَهُ رِيقُ رَسُولِ اللَّهِ ﷺ ثُمَّ حَنَّكَهُ بِالتَّمْرَةِ ثُمَّ دَعَا لَهُ فَبَرَّكَ عَلَيْهِ وَكَانَ أَوَّلَ مَوْلُودٍ وُلِدَ فِي الإِسْلاَمِ فَفَرِحُوا بِهِ فَرَحًا شَدِيدًا لأَنَّهُمْ قِيلَ لَهُمْ إِنَّ الْيَهُودَ قَدْ سَحَرَتْكُمْ فَلاَ يُولَدُ لَكُمْ  

I set out (for migration to Medina) as I was in the advanced stage of pregnancy. I came to Medina and got down at the place known as Quba' and gave birth to a child there. Then I came to Messenger of Allah (may peace he upon him). He placed him (the child) in his lap and then commanded for the dates to be brought. He chewed them and then put the saliva in his mouth. The first thing which went into his stomach was the saliva of Messenger of Allah ﷺ. He then rubbed his palate with dates and then invoked blessings for him and blessed him. He was the first child who was born in Islam (after Migration).  

فَخَرَجْتُ وَأَنَا مُتِمٌّ فَأَتَيْتُ الْمَدِينَةَ فَنَزَلْتُ بِقُبَاءٍ فَوَلَدْتُهُ بِقُبَاءٍ ثُمَّ أَتَيْتُ رَسُولَ اللَّهِ ﷺ فَوَضَعَهُ فِي حَجْرِهِ ثُمَّ دَعَا بِتَمْرَةٍ فَمَضَغَهَا ثُمَّ تَفَلَ فِي فِيهِ فَكَانَ أَوَّلَ شَىْءٍ دَخَلَ جَوْفَهُ رِيقُ رَسُولِ اللَّهِ ﷺ ثُمَّ حَنَّكَهُ بِالتَّمْرَةِ ثُمَّ دَعَا لَهُ وَبَرَّكَ عَلَيْهِ وَكَانَ أَوَّلَ مَوْلُودٍ وُلِدَ فِي الإِسْلاَمِ  

That she conceived ʿAbdullah bin Az-Zubair. She added, "I migrated to Medina while I was at full term of pregnancy and alighted at Quba where I gave birth to him. Then I brought him to the Prophet ﷺ and put him in his lap. The Prophet ﷺ asked for a date, chewed it, and put some of its juice in the child's mouth. So, the first thing that entered the child's stomach was the saliva of Messenger of Allah ﷺ. Then the Prophet rubbed the child's palate with a date and invoked for Allah's Blessings on him, and he was the first child born amongst the Emigrants in the Islamic Land (i.e. Medina). (Using translation from Bukhārī 3909)  

فَخَرَجْتُ وَأَنَا مُتِمٌّ فَأَتَيْتُ الْمَدِينَةَ فَنَزَلْتُ بِقُبَاءَ فَوَلَدْتُهُ بِقُبَاءَ ثُمَّ أَتَيْتُ بِهِ النَّبِيَّ ﷺ فَوَضَعْتُهُ فِي حِجْرِهِ ثُمَّ دَعَا بِتَمْرَةٍ فَمَضَغَهَا ثُمَّ تَفَلَ فِي فِيهِ فَكَانَ أَوَّلَ مَا دَخَلَ فِي جَوْفِهِ رِيقُ رَسُولِ اللهِ ﷺ قَالَتْ ثُمَّ حَنَّكَهُ بِتَمْرَةٍ ثُمَّ دَعَا لَهُ وَبَرَّكَ عَلَيْهِ وَكَانَ أَوَّلَ مَوْلُودٍ وُلِدَ فِي الْإِسْلَامِ  

"عَنْ أَسْمَاءَ بِنْت أَبِي بَكْرٍ أَنَّهَا حَمَلَتْ بِعَبْدِ اللهِ بْنِ الزُّبَيْرِ قَالَتْ: فَخَرَجْتُ وَأَنَا (مُتِمَّ (*)) فَأَتَيْتُ المدِينَةَ فَنَزَلْتُ بِقُبَاءَ فَوَلَدْتُهُ بِقُبَاءَ، ثُمَّ أَتَيْتُ بِهِ النَّبِيَّ ﷺ فَأَخَذَهُ فَوَضَعَهُ فِي حجْرِهِ، ثُمَّ دَعَا بِتَمْرَةٍ فَمَضَغَهَا ثُمَّ وَضَعَهَا فِي فِيهِ، فَكَانَ أَوَّل شَيْءٍ دَخَلَ فِي فِيهِ رِيقُ رَسُولِ اللهِ ﷺ ثُمَّ حَنَّكَهُ بِالتَّمْرَةِ، ثُمَّ دَعَا وَبَرَّكَ عَلَيْهِ وَسَمَّاهُ عَبْد اللهِ، فَكَانَ أَوَّل مَولُودٍ ولُدَ فِي الإِسْلَامِ".