Abu Sa'id Khudri (RAA) narrated that the Messenger of Allah (ﷺ) said:

"The (legal) slaughtering of the fetus is included when its mother is slaughtered." Related by Ahmad and Ibn Hibban graded it as Sahih.

وَعَنْ أَبِي سَعِيدٍ اَلْخُدْرِيِّ ‏- رضى الله عنه ‏- قَالَ: قَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{

ذَكَاةُ اَلْجَنِينِ ذَكَاةُ أُمِّهِ

} رَوَاهُ أَحْمَدُ, وَصَحَّحَهُ اِبْنُ حِبَّانَ (1758)‏ .‏