This is a qualitative study which has the aim to understand the perspective of the nursing professionals who have been working in the obstetric center at the University Hospital of University of São Paulo, and who are facing a process of organizational change.

The proactive change made in the service was:

the participation of a companion during the admission of the pregnant woman in the obstetric center. The data collection was done by interviews, in two different phases: the first interview was done to evaluate the professional's opinion before the proactive change and the second after the change was made. The analysis of the narratives allowed us to recognize and understand the common anxieties, the self defense mechanisms and the collective strategies of defense or team's acceptance related to the problems and opportunities that emerged during the change. In the nursing professionals' accounts it was valued the importance of orientation, the support given by the leader and the integration of the team. They also pointed out advantages as, the reduction of the pregnant woman's loneliness and the companion's stress. The physical structure was seen as something that makes this process difficult. During the first part of the research the nursing professionals showed insecurity and resistance related to the change proposed. In the second part, the positive experiences made the team stronger and improved the understanding of the need of the pregnant women and their relatives. In professional terms, this study is related to the development of the assistance with the delivery.