Asma reported that she was pregnant with Abdullah bin Zubayr in Mecca. She said, "I left Mecca when my pregnancy was at full term and arrived in Medina, where I stayed at Quba and gave birth to him there. Then I brought him to the Messenger of Allah ﷺ and placed him in his lap. He called for a date, chewed it, and then placed it in the baby's mouth. So the first thing to enter his stomach was the saliva of the Messenger of Allah ﷺ. Then he rubbed the chewed date on the baby's palate, prayed for him, and blessed him. He was the first child born in Islam, and the people rejoiced greatly at his birth, because they had been told that the Jews had cast a spell on them so that no children would be born to them."
أنها حملت بعبد الله بن الزبير بمكة قالت: فخرجت وأنا متم، فأتيت المدينة، فنزلت قباء، فولدت بقباء، ثم أتيت به رسول الله ﷺ فوضعته في حجره، ثم دعا بتمرة فمضغها ثم تفل في فيه، فكان أول شيء دخل جوفه ريق رسول الله ﷺ، ثم حنكة بالتمرة، ثم دعا له فبرك عليه، وكان أول مولود ولد في الإسلام. ففرحوا به فرحا شديدا، لأنهم قيل لهم: إن اليهود قد سحرتكم فلا يولد لكم.
Bukhari narrated it in the Book of Aqiqah (5469), and Muslim in the Book of Manners (26:2146), both through the route of Abu Usama, who said, Hisham bin Urwa narrated to us, from his father, from Asma bint Abu Bakr, who said, and then she mentioned it.