I asked the Messenger of Allah ﷺ about the embryo. He replied: Eat it if you wish. Musaddad's version says: we said: Messenger of Allah, we slaughter a she-camel, a cow and a sheep, and we find an embryo in its womb. Shall we throw it away or eat it? He replied: Eat it if you wish for the slaughter of its mother serves its slaughter.  

سَأَلْتُ رَسُولَ اللَّهِ ﷺ عَنِ الْجَنِينِ فَقَالَ كُلُوهُ إِنْ شِئْتُمْ وَقَالَ مُسَدَّدٌ قُلْنَا يَا رَسُولَ اللَّهِ نَنْحَرُ النَّاقَةَ وَنَذْبَحُ الْبَقَرَةَ وَالشَّاةَ فَنَجِدُ فِي بَطْنِهَا الْجَنِينَ أَنُلْقِيهِ أَمْ نَأْكُلُهُ قَالَ كُلُوهُ إِنْ شِئْتُمْ فَإِنَّ ذَكَاتَهُ ذَكَاةُ أُمِّهِ  

The Prophet ﷺ said: The slaughter of embryo is included when its mother is slaughtered.  

عَنْ رَسُولِ اللَّهِ ﷺ قَالَ ذَكَاةُ الْجَنِينِ ذَكَاةُ أُمِّهِ