Sunan Ibn Majah, Hadith 3199 ⓘ
It was narrated that Abu Sa’eed said: “We asked the Messenger of Allah about the fetus. He said: ‘Eat it if you wish, for it is considered legally slaughtered with the slaughtering of its mother.’”
حَدَّثَنَا أَبُو كُرَيْبٍ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ الْمُبَارَكِ، وَأَبُو خَالِدٍ الأَحْمَرُ وَعَبْدَةُ بْنُ سُلَيْمَانَ عَنْ مُجَالِدٍ، عَنْ أَبِي الْوَدَّاكِ، عَنْ أَبِي سَعِيدٍ، قَالَ سَأَلْنَا رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ عَنِ الْجَنِينِ فَقَالَ " كُلُوهُ إِنْ شِئْتُمْ فَإِنَّ ذَكَاةَ الْجَنِينِ ذَكَاةُ أُمِّهِ " .
also referenced under: Book 27, Hadith 3320 (In-Book) & Volume 4, Book 27, Hadith 3199 (DarusSalam)