This study was aimed at analyzing the process through which nurse-midwives have given meaning to unmedicalized attention. It is a qualitative study based on the Grounded Theory. Data were obtained and analyzed between February and April of 2006. Eight nurse-midwives who adopt the unmedicalized approach as orientation in their practice were interviewed. Through the analysis of the data it was possible to identify four categories--thinking about her practice; characterizing as medicalized the obstetric practice in hospitals; feeling annoyed by medicalized attendance; and identifying the principles of unmedicalization--, whose integration made possible to identify the process of building the meaning of unmedicalization. Respect to Physiology, as well as not to use unnecessarily interventionist practices as routine, constituted principles of unmedicalization. The reflection about their lives and the characterization of the obstetric practice in hospitals as medicalized were part of the nurses' mental process to revert the construction of the abilities acquired in the biomedical model.