Yahya related to me from Malih from Nafi from Abdullah ibn Umarthat the Messenger of Allah, may Allah bless him and grant him peace,forbade the transaction called habal alhabala. It was a transactionwhich the people of Jahiliya practised. A man would buy the unbornoffspring of the unborn offspring of a she-camel.
USC-MSA web (English) reference: Book 31, Hadith 62
Arabic reference: Book 31, Hadith 1354