Gross and fine motor milestones in the first two years of life - representative data for Germany

This paper analyzes the development of 18 gross and fine motor development steps (milestones) in the first two years of life and presents norms for children with normal birth weight and underweight children. The data come from a research project with more than 3400 parents, mainly in Germany, who participated. Using a “citizen-science approach,” parents reported their children's developmental progress online based on a calendar that charts 14 gross and four fine motor skills from birth to the point when children manage to walk. Only small and insignificant differences in reaching milestones were found between girls and boys. In addition, no impact of kind of delivery, nutrition, size at birth, siblings, age of mothers, social status of parents, and month of birth on motor development was found. However, preterm or underweight newborns showed a significant delayed motor development compared to newborns with normal birth weight. Therefore, separate norm values are presented for the total sample and for normal birth weight and underweight children.