Research shows that babies are better protected if they stay rear-facing as long as possible. In fact, a recent study found that children in their second year of life are 5 times less likely to die or have serious injuries in a crash if they are rear-facing. In order to keep your child rear-facing longer, you will need to choose a car seat with rear-facing weight limits of about 30 to 35 pounds. If your car seat only rear-faces to 20 to 22 pounds, you may need to move your baby into an infant only or convertible car seat with a higher rear-facing weight limit.
The American Academy of Pediatrics recommends children should ride facing the rear as long as possible and to the highest weight and length allowed by the manufacturer of the seat.