Advocacy has been positioned as an ideal within the practice of nursing, with national guidelines and professional standards obliging nurses to respect patients' autonomous choices and to act as their advocates. However, the meaning of advocacy and autonomy is not well defined or understood, leading to uncertainty regarding what is required, expected and feasible for nurses in clinical practice. In this article, a feminist ethics perspective is used to examine how moral responsibilities are enacted in the perinatal nurse—patient relationship and to explore the interaction between the various threads that influence, and are in turn affected by, this relationship. This perspective allows for consideration of contextual and relational factors that impact on the way perinatal nursing care is given and received, and provides a framework for exploring the ways in which patient autonomy, advocacy and choice are experienced by childbearing women and their nurses during labour and birth.