The exact number of people affected by intellectual and developmental disabilities (IDDs) is unknown. This is because IDDs cover a wide range of conditions, many of which are diagnosed several years after birth, rather than in newborns.
Current estimates suggest that 2% to 3% of children in the United States have some form of intellectual disability.1
According to the Centers for Disease Control and Prevention (CDC), about 1 in 33 newborns (or 3%) in the United States are born with conditions related to problems in prenatal development.2
For current statistics on the number of children born with specific types of these conditions, visit the CDC Data and Statistics webpage on birth defects.