Introduction - The implementation of low-emission mobility zones (ZFE-m), a flagship measure in the fight against air pollution, sometimes faces a lack of public acceptance. To support the planning of these zones, the Île-de-France Regional Health Observatory (ORS), in collaboration with Airparif and Santé publique France, has developed an innovative approach for the prospective assessment of their health benefits. An illustration of the expected benefits regarding the incidence of childhood conditions (asthma and low birth weight) is presented in this article. Method - This prospective assessment is based on quantitative health impact assessment (QHIA) methods. It relies on concentration-risk relationships that compare the frequency of the studied health effects with an exposure differential. The latter was estimated by cross-referencing building-level georeferenced population data with reductions in nitrogen dioxide (NO₂) concentrations modeled by Airparif at a high resolution. The expected number of new cases of preventable childhood diseases resulting from these reductions was assessed within a study area bounded by the Francilienne ring road, for four scenarios of implementing a ZFE-m (two perimeters and two restriction levels studied). Results - This assessment indicates that implementing the measure would yield health benefits, regardless of the scenario considered, and that the "perimeter" parameter is at least as critical as the "restriction level" parameter. Thus, between 50 and 170 low-birth-weight births and between 830 and 2,930 annual asthma cases, or between 190 and 700 emergency room visits for asthma, could be prevented. The results also show that populations residing beyond the restriction perimeter would also benefit from improved health.