Exposure of pregnant women to fine particulate matter<2.5μm in diameter (PM_2.5) is responsible for low birthweight (LBW) and intellectual disabilities, as expressed by a lower intelligence quotient (IQ). We estimated the attributable cost due to PM_2.5 of healthcare at birth and cognitive retardation of children with LBW in metropolitan France in 2012. The cost of specific care of the 8300 (range, 3100–13,300) children born every year in France with a LBW attributable to PM_2.5 exposure is estimated at €25 million (range, € 9.5–39 million). Among these 8300 children, 1880 will present an intelligence quotient (IQ) lower than the average of the general population. The annual cost of the care of these intellectual deficiencies attributable to PM_2.5 is estimated at €15 million and that of the mental handicap on the lifespan of the LBW children born in 2012 attributable to PM_2.5 is estimated at €1.2 billion (range, €458 million to €1.9 billion). Beyond the elevated costs borne by future generations and the intellectual impoverishment of our society, it is essential to provide continued minimal monitoring of pregnant women exposed to air pollution. For the decision-makers, it is urgent to take effective measures and actions to protect the health of exposed populations.