This editorial highlights some of the emerging threats and risks to children health, including birth defects, psychological behavioral problems, neurodevelopmental disorders and health risk behaviors, which will continue to have increased impact on healthy growth and development. Mounting evidence has confirmed the adverse effects of environmental exposure during preconception and pregnancy on children's health, which suggests that one of the best investments we can make to achieve lasting progress in global health is the prevention of children's health problems during the first thousand days of life and beyond.