This descriptive and exploratory study was carried out through interviews with 221 puerperal women who gave birth in Sao Paulo State public maternities located within the capital. The purposes of the work were: 1. to identify the type of childbirth women expected to have--whether vaginal births or cesareans--and why; 2. to verify to what extent women's expectations corresponded to the type of birth they had; 3. to compare medical indications for c-sections with women's understanding of justifications they were given for this intervention. Data revealed that 74.7% of the women expected to have vaginal births and 25.3% expected to have cesarean sections. Vaginal birth, expected by 165 interviewees, occurred in 66.1% of these cases. Among women who expected having vaginal births, the most mentioned justification was that recuperation afterwards was faster. Among women who expected cesareans, the most mentioned justification was a previous c-section. The justifications presented by 61 women for having been submitted to c-sections did not coincide with medical indications for this intervention in 47.5% of the cases.