[Births in Brazilian Birthing Centers: a research protocol]

In Brazil, Freestanding Birth Centers (FBC) are defined as health units linked to hospitals that may be located within these facilities (alongside birth center - ABC) or in their surroundings (FBC). The Brazilian Ministry of Health has defined the physical and care structure of FBC. Their care model includes appropriate practices, good maternal and infant outcomes, and the promotion of positive experiences for women during childbirth. Births in Brazilian Birthing Centers is a nationwide cross-sectional study aimed to evaluate the structure of FBC to care for usual births risks, assess labor and birth care in FBC, and compare the research outcomes with those of usual births risks in the hospitals within Birth in Brazil II. This article aims to inform the design and methodological steps proposed for Births in Brazilian Birthing Centers. In total, eight FBC were chosen. The sample included service managers and 1,560 female users. Data collection were collected from August 2022 to October 2024. Study variables and instruments, the stages of data collection from admission up to 120 days after childbirth, the research team's activities, the data analysis plan, and the ethical aspects are shown and the relevance of disseminating this research protocol and the specificities of research in Birthing Centers are discussed.