Always check the seat’s instructions for specific weight and height restrictions.
The baby’s weight, length, age and development are the four factors to consider when using a rear-facing seat. Use a rear-facing seat from birth until the baby is either too tall or too heavy according to the weight and height limits given in the car seat instruction manual. A child must be kept rear-facing until he or she is one year of age and 10 kg (22 lbs.) and can walk. Do not rush to move your baby forward-facing. A rear-facing seat is the safest way for your child to travel. Some seats can rear face up to 22.7 kgs (50 lbs).
Many caregivers choose an infant only car seat as their child’s first seat. Infant only seats can only be used rear facing, and will attach in and out of a base that is installed into a vehicle. Infant only seats often have lower weight maximums than other types of rear-facing seats such as a convertible seat (one that rear faces and forward faces) or a 3-in-1 seat (one that rear faces, forward faces, and can be used as a booster). Once a child outgrows his infant only seat, he should graduate to a convertible or 3-in-1 seat and use it rear-facing until he is either too heavy or too tall for the seat according to its instruction manual.
Babies and young children have large heads and weak neck and back muscles. Rear facing seats face “backwards” so that the force of a crash or sudden stop is spread across the baby’s back and supported by the car seat. A baby’s neck and back muscles are not strong enough to withstand forces during a crash and therefore must be supported by the seat.
