This study aims to understand the meanings given by poor and midle class Brazilian women to the so called humanizes birth, which became popular in Brazil upon the foufation of a civil organization called Rede pela Humanização do Perto e do Nascimento (ReHuNa). According to activists, the expression humanized birth, in general, refers to situations in which women s rights and choices are taken in consideration at the time of birth. More frequently, howere, it refers also to the idea of a natural birth, an expression that means the commitment to minimal medical and pharmacological interventions. The meanings given to these expressions become respectively more and less approximated according to the context in which they are used. This became particularly evident in this research, since it involves two fieldworks: the first are prenatal preparation classes, mainly attended by middle income women, offered in the Southem Zone of Rio de Janeiro by an activist. The Second is public birth center that is considered a reference by the humanization movement. This birthcenter is situated in the Wesrem Zone and is mainly attended by low income womem. The Study s results suggest that the humanization birth approach has different meanings for women according to the socioeconomic group of which they are part. Middle class women give special importance to the reduction in pharmacological intervention and to the body experience, considered to provide a subjective growth. The poor women value specially the way in which they are treated by the nurses/midwives.