Pursuant to the legal principle, the fetus is presumed to have been born for the purposes of inheritance. The principle was reified in Roman law and continues to be implemented today in most European nations, in the Americas (where the fetus is sometimes legally considered to be a person), and in South Africa.
This follows from the legal axiom, which holds that a fetus is considered to have been born for the purposes of succession. The concept was codified in Roman law and remains in force in many European nations, the Americas, and South Africa.