This paper investigates the relationship between population growth and economic growth, through the study of fertility choices and their effects on natural resources. It aims to analyze the interactions between endogenous fertility choices and environment. We analyze a growth model driven by natural resources and without production, where agents have jointly to determine consumption and fertility, taking into account the effect of their decisions on the dynamics of natural resources. In our model, even if renewal capacity of natural resources is unbounded, not always a sustainable path, where both population and natural resources coexist, can be found: it depends on the stationary fertility level. Moreover, the planner, through policies oriented to improve public attention to environment protection or to modify the intensity of the dilution effect, can affect the growth rate of population and of the overall economy: this is an indirect effect working through the interaction between fertility, population and economic growth. In particular, through certain kind of policies, the planner can affect the fertility (or the mortality) rate in order to reach a sustainable path.