Musannaf Ibn Abi Shayba 18:1330

Abu Bakr narrated to us, he said: Abd al-A’la narrated to us, from Ma’mar, from al-Zuhri, that he used to say: If a woman is killed while she is pregnant, there is a blood money (diya) and a ghurra (compensation for the fetus), even if she did not deliver it.