The period from pregnancy through age three is the one in which the most rapid growth of the brain and behavior occurs. Yet most researchers and policy makers have treated the nine months of development during pregnancy separately from the first three years of life.
Prenatal experiences are part and parcel of the postnatal experience of mothers and their babies; the postnatal period is sometimes referred to as the fourth trimester, a way to highlight the fact that after a child’s birth, mothers themselves need continuing services and screening. Indeed, children’s wellbeing very much depends on their mothers’ health and wellbeing. The title of this issue of the Future of Children, “Three Trimesters to Three Years,” highlights continuity in development, the continuing intersection of mother and baby, and the rapid growth that occurs from conception to three years of age.