[Intermunicipal healthcare flows and perinatal births and deaths in Greater Metropolitan Rio de Janeiro, Brazil, in 2011 and 2014].

The regionalization of perinatal care should consider existing healthcare structures for facilitating access. This spatial-temporal ecological study identified intermunicipal flows of perinatal births and deaths in Greater Metropolitan Rio de Janeiro, Brazil, in 2011 and 2014, defined parameters, and systematized proposals for organizing the regionalization of perinatal care. The data sources were the Brazilian Information System on Live Births, Mortality Information System, National Registry of Healthcare Establishments, and 2010 Population Census. The study identified existing relations between the mothers' municipalities of residence and the occurrence of perinatal births and deaths. Each municipality was analyzed singly and pairwise (residence/occurrence) according to the vital event, healthcare resources, and pragmatic criteria of life-threatening conditions at birth. We conducted descriptive analyses of dominant flows, exploratory principal components analysis, and cluster analysis. The existing healthcare networks were identified, and 47 variables were summarized in three factors (analytical dimensions) - availability of beds, risk of life-threatening conditions, and socioeconomic status - accounting for 60%/80%, 20%/30%, 13%/22%, respectively, of the variance pertaining to each year analyzed. The factors were used to form clusters, classified in 3 to 5 strata. Three proposals were drafted for perinatal health regions. The study's principal contribution was having presented parameters for monitoring the regionalization and systematic reevaluation of this process based on administrative records.