This chapter traces the emergence of endometriosis as a pathological diagnosis between 1861 and 1949, revealing how modern gynecology developed through a gendered, racialized, classist, and ableist lens. Drawing on archival research and feminist disability studies, it argues that endometriosis was not simply discovered: it was constructed through the anxieties of patriarchal medicine, which pathologized infertility, pain, and deviance from reproductive norms. Physicians from Carl von Rokitansky to John A. Sampson laid the groundwork for clinical recognition of the disease, but it was Harvard gynecologist Joseph Vincent Meigs who redefined endometriosis as a moral and social failure of educated, childfree white women. His eugenic framing transformed the disease into a disciplinary mechanism that punished feminist agency and class mobility. The chapter examines how medical narratives dismissed pain as hysteria, enforced reproduction as cure, and ultimately positioned infertility as disability. By situating endometriosis within broader debates around normalcy, biopower, and reproductive citizenship, this chapter demonstrates how the disease has historically been used to regulate gender, ability, and whiteness. These early constructions continue to shape diagnostic pathways and clinical assumptions today. Through a critical analysis of medical texts, cultural tropes, and disability theory, this chapter reframes endometriosis as a historically contingent and politically charged site of embodied control.