'A'isha reported that it had been revealed in the Holy Qur'an that ten clear sucklings make the marriage unlawful, then it was abrogated (and substituted) by five sucklings and Allah's Apostle (s.a.w.a.) died and it was before that time (found) in the Holy Qur'an (and recited by the Muslims).
Aishah said: "What was reavealed in the Qur'an was ten well-known sucklings, five were abrogated from that, so it became five well-knwon sucklings. Then the Messenger of Allah (s.a.w.a.) died and the matter remained like that..."
It was narrated that 'Aishah said:
"One of the things that Allah, the Mighty and Sublime, revealed" -(one of the narrators) Al-Harith said (in his narration): "One of the things that were revealed in the Qur'an"- "was that ten known breast-feedings make marriage prohibited, then that was abrogated and changed to five known breast-feedings. Then the Messenger of Allah passed away when this was something that was still being recited in the Qur'an."
Yahya related to me from Malik from Abdullah ibn Abi Bakr ibn Hazm from Amra bint Abd ar-Rahman that A'isha, the wife of the Prophet, may Allah bless him and grant him peace, said, "Amongst what was sent down of the Qur'an was 'ten known sucklings make haram' - then it was abrogated by 'five known sucklings'. When the Messenger of Allah, may Allah bless him and grant him peace, died, it was what is now recited of the Qur'an."
Yahya said that Malik said, "One does not act on this."