Maternal life style factors during pregnancy has been related to child neurodevelopment and behavioral problems. However, there is a need to further study them in combination as a general score and perform the analyses in a consortium of several European cohorts. The harmonization of mental health problems in several population-based birth cohorts will allow us to perform trajectory analyses with specific mental health domains. In this study, we will study the association of a maternal lifestyle score during pregnancy and the trajectories of internalizing and externalizing problems. These are the main domains in child neurobehavioral development. The creation of the lifestyle score will be based on different lifestyle variables reported during pregnancy: Smoking, Alcohol consumption, DASH diet, folic acid supplement, pre-pregnancy weight/height, sleep duration, physical activity and tv watching. We will create a maternal healthy lifestyle score (CHLS) using the dichotomous variables. The final summation of these variables will be used as the main exposure variable.