The American Academy of Pediatrics announced Monday that parents should keep toddlers' car seats facing the rear until at least age 2.

The pediatrics group categorizes its recommendation as "a significant change from previous AAP policy," though it sticks with earlier advice to keep children in convertible car seats until they reach those seats' height and weight limits. It recommends using booster seats until children are 4 feet 9 inches tall and between 8 and 12 years old, and keeping children younger than 13 in the back seat.

Previously, the AAP had advised parents to keep their children in rear-facing car seats for as long as the manufacturer's height and weight limits allowed, but also had set a minimum age to turn the seats at 1 year old and 20 pounds.

"Most people see their kids in terms of milestones -- that moving from one thing to another is really a positive thing," said Ben Hoffman, a member of the committee that drafted the statement and a University of New Mexico associate professor of pediatrics. "Turns out with car seat safety, it's not."

Rear-facing car seats distribute the impact of a crash along a larger surface area, which better protects young children, Hoffman said.

Infants and toddlers, whose heads are disproportionately large and heavy compared to the size of their bodies, are at particular risk for neck injuries in a car crash, said Leslie Frank, a Pittsburgh pediatrician.