The fetus is considered legally slaughtered with the legal slaughtering of its mother

Sunan Ibn Majah · Book 27 · Hadith 3199

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 ‏"‏ ‏.‏ قَالَ أَبُو عَبْ…

It was narrated that Abu Sa’eed said: “We asked the Messenger of Allah (ﷺ) about the fetus. He said: ‘Eat it if you wish, for it is considered legally slaughtered with the slaughtering of its mother.’”