Monsters in the Cabinet uses the historical collection of abnormal fetuses to examine how scientific knowledge about non-normative bodies was produced. It asks how the collection, anatomical study, and comparison of real embryos and fetuses with congenital abnormalities—once called monsters—produced scientific knowledge which was embedded with claims about how a body’s form marked its place in the natural and social orders. The dissertation uses a range of Dutch sources, such as the records of midwives, museum collections, public health topographies, and scientific publications. These reveal the networks, scientific practices, and conceptual frameworks that transformed a fetal body into a research object from which knowledge about nature and physiology could be extracted. Seeking to understand the historical relationship between “monstrous births” and disability, the dissertation shows how the scientific knowledge and professional expertise gained from the study of fetal bodies was applied to living people by medical practitioners. It demonstrates that the comparative, synthetic, and material study of “monstrous” bodies was the basis upon which a normal model of development was scientifically produced. Moreover, anatomical preparations elevated the scope and authority of medical expertise in a way that endowed physicians with substantial bureaucratic influence in the early-nineteenth century, particularly with regards to public health initiatives addressing infant and maternal mortality and poor relief for disabled citizens.