Sahih Bukhari Volume 7, Book 71, Hadith Number 655.

Narrated By Abu Huraira : Two ladies (had a fight) and one of them hit the other with a stone on the abdomen and caused her to abort. The Prophet judged that the victim be given either a slave or a female slave (as blood-money). Narrated Ibn Shihab: Said bin Al-Musayyab said, “Allah’s Apostle judged that in case of child killed in the womb of its mother, the offender should give the mother a slave or a female slave in recompense The offender said, How can I be fined for killing one who neither ate nor drank, neither spoke nor cried: a case like that should be denied ‘ On that Allah’s Apostle said ‘He is one of the brothers of the foretellers.”