Prenatal Equality of Opportunity ESZTER KOLLAR & MICHELE LOI ABSTRACT In this article, we defend a normative theory of prenatal equality of opportunity, based on a critical revision of Rawls’s principle of fair equality of opportunity (FEO).We argue that if natural endowments are defined as biological properties possessed at birth and the distribution of natural endowments is seen as beyond the scope of justice, Rawls’s FEO allows for inequalities that undermine the social conditions of a property-owning democracy.We show this by considering the foetal programming of disease and the possibility of germ-line modifications. If children of lower socioeconomic background are more likely to develop in a poor foetal environment and germ-line enhancements are available only to the rich, initial inequalities between the rich and the poor would grow, and yet FEO would be satisfied. In order to avoid the problem, we propose a revised FEO principle omitting any reference to the comparison of natural endowments. Our revised FEO requires that institutions mitigate social class effect from repro- duction and gestation to the greatest extent compatible with parental freedoms and the value of the family. 1. Introduction In this article, we defend a normative theory of prenatal equality of opportunity, based on a critical revision of Rawls’s principle of fair equality of opportunity (FEO).We argue that if natural endowments are defined as biological properties possessed at birth and the distribution of natural endowments is seen as beyond the scope of justice, Rawls’s FEO has problematic implications for the overall coherence of his theory. Our argument rests on three premises: (1) If natural endowments are defined as biological properties possessed at birth or conception, institutions that fully comply with FEO allow social inequalities to influence the distribution of natural endowments. (2) If children of lower socioeconomic background are more likely to develop in a poor foetal environment and germ-line enhancements are available only to the rich, natural inequalities would grow and yet FEO would be satisfied. (3) If social inequalities can influence the distribution of natural endowments that are beyond the scope of justice, they may give rise to excessive inequalities over time. The biological transmission of social advantage in the prenatal phase of life under- mines the tendency to equality and the social conditions of a property-owning democracy. We conclude that in order to avoid this problem FEO needs to be revised omitting any reference to the comparison of natural endowments. This has practical implications for the design of institutions. Our revised FEO is realised when social institutions mitigate Journal of Applied Philosophy doi: 10.1111/japp.12067 © Society for Applied Philosophy, 2014, John Wiley & Sons Ltd, 9600 Garsington Road, Oxford, OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA.