It is narrated that Umar (may Allah be pleased with him) said:
"O Messenger of Allah, I buried daughters alive during the Days of Ignorance."
So the Prophet (peace and blessings be upon him) said:
"Free a slave for every daughter you buried alive."
The "Maw'udah" (the buried-alive girl) refers to a daughter who was killed upon birth — a practice common among the people of Jahiliyyah out of fear of disgrace and poverty.
Ref: : Kitab Al-Majmu Sharh Al-Muhazzab Lil-Shirazi. Vol21, Pg21
Alkarbala