This chapter redefines autonomy in bioethics by foregrounding menstrual agency as a relational and embodied capacity, rather than an isolated expression of individual choice. It argues that menstrual health has been reduced to reproductive function, excluding the psychological, emotional, and social dimensions of menstruators’ lived experience. Despite being reduced and overlooked, the way menstrual health intersects with emotional, social, and cultural dimensions reveals that even in health, autonomy can be experienced as both vulnerability and agency. Drawing on a triadic approach to ailments and the enactive concepts of autonomy, agency, and precariousness, the chapter reconceptualises menstrual well-being as a shared ethical and social concern. In doing so, it challenges dominant notions of autonomy and calls for structural transformations that support menstruators in reclaiming agency over their menstrual lives.