The phenomenon of fertility is one of the most significant components of demographic changes in any country. Macroeconomic volatilities and uncertainties are among the influential factors affecting households' long-term decisions, such as marriage and childbearing. This paper investigates the impact of macroeconomic uncertainty on the fertility rate in Iran during the period 1971-2023 using the Nonlinear Autoregressive Distributed Lag (NARDL) model. The estimation results for the positive and negative changes in macroeconomic uncertainty on the fertility rate revealed that both coefficients are asymmetric, negative, and significant in the long run. This implies that economic stability, as a secure environment, strengthens families' inclination towards childbearing, while economic volatilities postpone this tendency. Furthermore, the results indicate that, in the long run, the effects of women's employment and human capital on the fertility rate are positive and significant, whereas the effects of per capita GDP, marriage rate, infant mortality rate, old-age dependency ratio, unemployment rate, and urbanization rate on the fertility rate are negative and significant.