Prenatal health care emerged in the early twentieth century amidst immigration anxieties, urban squalor, and global consciousness. As physicians and public health departments began to campaign for the medical surveillance of all pregnant women, they framed their arguments in terms of gender, race, nationalism, and civilization. While the practical advice provided by these newly-minted experts on pregnancy was virtually the same as it had been for decades (guidance on diet, rest, care of bowels, and clothing), medical personnel attempting to convince pregnant women to seek medical attention as frequently as every two weeks throughout their entire nine-month pregnancies couched this advice in a new context, tapping into a new American psyche. Creating the image of “American” pregnancy as one of a white, native-born, middle or upper-class woman, doctors relied on comparisons to recent immigrants, “primitive” groups, and European populations to convince women of the importance of medical supervision during pregnancy, to save both their babies and the nation itself. This paper examines the rhetoric of prenatal care with a focus on the language and arguments employed by early twentieth-century physicians, which continue to shape both private and public policing of pregnant bodies, women’s rights, and reproductive justice.