In France, the maternal and child protection service, in charge at the departmental level of the organization of health check-ups in nursery schools for 4-year-old children, conducted a study to explore, over three school years (2018 -2019, 2019-2020 and 2020-2021), the evolution of the height and weight status of children and to estimate the impact of the health crisis due to SARS-CoV-2 in the Val-de-Marne district.