Introduction
Both in Sweden and around the world, there is a trend towards an increase in the number of medical interventions during labour, such as caesarean births and the use of synthetic oxytocin for labour augmentation due to prolonged progress [Previous literature has described how the architectural design of healthcare facilities can impact the wellbeing, stress levels, healing processes and behaviours for all users, including admitted patients, companions, and care providers [This study reports on the implementation of a new birthing room, which was redesigned to support women’s physiological process of birth and was evaluated in the Swedish Room4Birth RCT [The implementation of the new room was a complex intervention as it was embedded in a context with medico-technical requirements, human interactions, and individual and organisational needs. To understand how this complex intervention worked and to provide knowledge about the mechanisms that influenced its implementation [