摘要：Being largely diversified along the urban–rural gradient, fertility gaps have demonstrated to fuel metropolitan expansion, contributing to natural population growth and social change. In this direction, population dynamics and economic transformations have continuously shaped urban cycles in Europe. Assuming suburban fertility to be a relevant engine of metropolitan growth, the present study investigates and discusses the intrinsic relationship between fertility transitions and urban expansion, focusing on European metropolitan regions. An average crude birth rate referring to the last decade (2013–2018) was estimated from official statistics at 671 Functional Urban Areas (FUAs, Eurostat Urban Audit definition) of 30 European countries, distinguishing ‘central cities’ from ‘suburban’ locations. Local contexts with a higher crude birth rate as compared with neighboring settlements were identified analyzing differential fertility levels in urban and suburban locations. By providing an indirect, comparative verification of the ‘suburban fertility hypothesis’ in European cities, the results of this study demonstrate how suburbanization has been basically associated to younger and larger families—and thus higher fertility levels—only in Eastern and Southern Europe. Birth rates that were higher in suburbs than in central cities were observed in 70% of Eastern European cities and 55% of Mediterranean cities. The reverse pattern was observed in Western (20%), Northern (25%) and Central (30%) Europe, suggesting that urban cycles in the European continent are not completely phased: most of Western, Central, and Northern European cities are experiencing re-urbanization after a long suburbanization wave. Demographic indicators are demonstrated to comprehensively delineate settlement patterns and socioeconomic trends along urban–suburban–rural gradients, giving insights on the differential metropolitan cycles between (and within) countries.
