This chapter examines the status of the fetus in medieval theology and the law, focusing on the ways theories about the workings of procreation and producing healthy offspring informed religious and legal norms about marriage, sex and childbearing. Through the Christian doctrine of the immortal soul, the fetus became the subject of intertwining religious, philosophical, legal and social concern. Debates about abortion, infant baptism and burial related to each other and also to discussions about the nature of seeds, the formation of the embryo, ensoulment and the body/soul nexus, and to questions about humanity, legal personhood and salvation. Similar questions underlay discussions about monstrous births, the cause of which sharply divided opinion, with important implications for their spiritual and legal status. These divergent views lead to the broader question of whether, why and how norms and rules about marriage, sex and procreation reflected attitudes about physical and mental impairment and the production of healthy and beautiful children. The pastoral ideology promoted procreation and underscored the unity of humankind, combining a concern for survival of offspring and the stability of marriage with indifference about health. However, in the later Middle Ages new ideas challenged the hegemony of the pastoral view.