This article presents a part of the results of an empirical study conducted at a Parisian hospital between 2011 and 2014. It aimed at understanding the women and couples’ motivations to terminate or not a pregnancy once a prenatal diagnosis has revealed a genetically related disease in the embryo or fetus. The article first presents the social and legal context of the study, the methodology used and the pathologies that were encountered. Then, it examines the results of the interviews conducted (...) with 5 women alone and 23 couples explaining their reasons for deciding to terminate or not the pregnancy. Finally, it explores the patients’ views about the doctor’s involvement in the decision-making process. The findings reveal the reasons they formulate when they ponder whether to terminate or not the pregnancy. It highlights the process of their deliberation, their hierarchisation of arguments and concerns. They also show how patients, though often consumed in sorrow, claim to be the legitimate decision-makers, especially women, in a social and legal context in which the rejection of eugenics is viewed as an undisputable principle. (shrink)