Getting Started

You'll start with your newborn in an infant car seat. As your child grows, you'll need to buy a succession of car seats to maintain a consistently safe and comfortable fit. But which seat should you use when? Use this car seat guide to gauge when it's time to sit tight or move up to the next level.

Use an infant car seat (always rear-facing) from birth until your baby reaches the seat's height and weight limits. Weight limits are typically 22 pounds, but sometimes higher depending on the model. Weight limits are listed on the seat and in the instruction manual. When your baby reaches the seat's limits, which may be as soon as 6 to 9 months old, you'll need to switch to a convertible car seat in order to keep her rear-facing at least until her first birthday.

Use a convertible car seat rear-facing until your baby is at least 1 year old and weighs 22 pounds or more. Some convertible seats can be used in the rear-facing position for children who weigh up to 30 to 35 pounds. And research shows that babies are safest in a rear-facing orientation so it's best to keep them that way for as long as you can. When your baby reaches a convertible seat's height and weight limits in the rear-facing mode, switch the seat around, and use it facing forward until your toddler reaches the height and weight limits for the forward-facing seat. Weight limits for most are generally up to 40 pounds, though more and more convertible models have weight limits up to 65 pounds or more.

As an alternative to a convertible seat that can face forward, some seats are forward-facing only. The front-facing-only seat is used with an internal harness for toddlers, who typically weigh from 20 to 40 pounds, though some models can be used with the internal harness at higher weights. The internal harness can then be removed and the forward-facing seat can be used as a belt-positioning booster for children who weigh from 60 to 80 pounds, depending on the model.

When your child reaches the weight and height limits of the harness system of the convertible or front-facing-only seat, it's time for either a belt-positioning or standard booster seat for your child. Boosters raise the child up in the vehicle seat to allow the safety belt to pass correctly across their sternum (not their neck) and low across the child's upper thigh (not their abdomen). Both use the vehicle's safety belt to restrain the child but belt-positioning models also have some sort of belt guide to better position the safety belts over a child's shoulders.

When your child is tall enough to use the car's safety belts, typically at least 57 inches and from 8 to 12 years old, and can ride comfortably seated in the vehicle's seat, she can ride with just a car's safety belts. Even with a safety belt, all children under age 13 should ride in the back seat.

The types of car seats available include infant car seats, travel systems, convertible seats, toddler booster seats, belt-positioning booster seats, built-in seats, and special seats. From birth until your child reaches a height of 4 feet 9 inches, he will potentially go through several car seats before being ready for the vehicle belts alone.

Discount stores such as Kmart, Target, and Wal-Mart, and baby superstores such as Babies-R-Us and Baby Depot offer the largest selection of car seats. Department stores are also a good source for child seats. You'll generally have to go to a specialty boutique to find higher-end models such as Britax and Orbit. Wherever you shop, ask to take the child seat outside to make sure it's compatible with your car. If the store won't let you, at least make sure you can return the seat if it doesn't work out-or go to another store.

Types

There are several types of car seats available. Choose the appropriate car seat based on your child's age, weight, and height.

These rear-facing seats-the first stage-are a must for babies up until their first birthday and until they weigh at least 20 pounds. A built-in harness secures the infant facing rearward at an incline that provides optimum protection in a crash without interfering with breathing. Most infant seats now have weight capacities of 22 pounds or more.

Safety data show that keeping an infant facing rearward in an infant seat for as long as possible offers the best protection. With its removable carrier and swing-up handle, an infant seat lets you move your baby in and out of the car without disturbing him. (Make sure the seat is always properly inclined so your baby's head doesn't fall forward and obstruct its airway. And don't place the seat on a high surface.)

Once your infant grows too big or too tall for an infant seat, you'll have to switch to a larger-capacity seat or a convertible car seat. Though it might be tempting to jump to the next stage-a convertible seat-at birth, an infant seat is often more compact and secure during the early months.

Many car-seat manufacturers offer a combination consisting of an infant car seat, a mounting base for your car, and a separate stroller. Snapping the infant carrier into the wheels creates a stroller system, with the infant facing you as you push. Many stand-alone strollers can also accommodate infant car seats from various manufacturers-or you can buy an empty stroller frame.

A travel system lets you move a sleeping baby from car to stroller and vice versa without disturbing it.

Travel systems can be bulky. If you're a city dweller who has to negotiate subway stairs, or if the trunk of your car has limited space, a separate car seat and compact stroller might be a better choice.

These allow either a front- or rear-facing seating position, with the child secured by a built-in harness. Facing the rear, convertible seats can hold an infant up to at least 1 year old and weighing up to 35 pounds, in most cases. Facing front, most can accommodate toddlers up to 40 pounds. (More models are becoming available with weight limits as high as 80 pounds.)

Convertible models eliminate the need to switch seats when your infant becomes a toddler. And their higher weight capacities allow you to keep even larger babies facing the rear, safer orientation longer.

They don't offer the convenience of a separate carrier, and they're not compatible with strollers, so you'll have to transfer your baby to a carriage or stroller when you set out on foot, a problem if you take your child on frequent errands.

These front-facing seats with a built-in harness look like oversized convertible seats, but they secure a child only in a front-facing position. When the child reaches 40 pounds (some seats go higher), removing the harness converts the seat into a booster, which positions the child to use the car's safety belts. Use a booster until the child weighs about 80 pounds and is at least 57 inches tall-the minimum height at which a car's safety belts fit properly without a booster. In their booster mode, some models accommodate children weighing as much as 100 pounds.

The ability to accommodate a wide range of sizes and weights increases these seats' useful life.

Some high-backed models can interfere with some car head restraints.

Boosters lack a built-in harness and are designed to be used only with the vehicle safety belts. They lift the child so the shoulder strap fits properly across the child's shoulders and the lap strap goes across the upper thighs. High-back, low-back, and no-back models are available. Belt-positioning boosters have a high back and include a built-in guide that helps position the car's shoulder belt even better so it doesn't ride across the child's face or neck. A no-back booster is simply a cushion, essentially a "telephone book" that raises the child so the safety belts fit properly.

Many are relatively inexpensive. Those with belt-positioning guides can accommodate differences in belt position in various cars.

Boosters can tempt parents to stop using a seat with a harness prematurely, just because boosters allow the car safety belts to fit properly. The latest safety research shows that it's best to keep children in a harness as long as possible before switching them to a booster.

Some cars and minivans offer an integrated, forward-facing booster seat for toddlers weighing more than 20 pounds.

They're convenient to use and easy to convert back to a standard seat for adults or older children.

They offer little protection in a side impact, and they're often in an outboard rear seating position, rather than in the safer center of the seat. You'll still need a proper child restraint when your child rides in other vehicles.

Small car beds are available for preemies and other very small newborns who might not fit securely in a conventional infant car seat and might need to lie flat to maintain proper breathing. In addition, you can buy specially designed car seats for children with breathing problems and other physical disabilities. Consult your pediatrician, visit the Automotive Safety Program at www.preventinjury.org, or call 800-543-6227.

Features

Some car-seat features provide important safety and convenience benefits. Others are frills. Before you buy, consider the following features.

Since Sept. 1, 2002, all child car seats with a built-in harness and nearly all passenger vehicles sold in the U.S. have included equipment designed for simpler child seat installation. That system, called LATCH (Lower Anchors and Tethers for Children), consists of child car-seat connections that attach to anchor points in the vehicle. You can still use the vehicle safety belts to install a LATCH-equipped child car seat in an older car that lacks LATCH anchors. The system isn't perfect. The anchors in many cars are hard to reach. And most vehicles have LATCH anchors only on the outboard positions of the rear seat, rather than in the center, which is the safest. Despite its flaws, LATCH installation eliminates some of the incompatibilities that may exist when you use the vehicle safety belts to install a child seat.

Most infant, convertible, and toddler seats have a built-in adjustable five-point harness system, with two straps over the shoulders, two for the thighs, and a crotch strap. A five-point harness system is more secure than a three-point system, with two shoulder straps that come together at a buckle in the shell or a crotch strap. The extra straps spread the forces of a crash more evenly across a child's body. The thigh and crotch straps also help prevent 'submarining', or sliding out of the harness in a crash (as is possible with a three-point harness).

They let you adjust the height of the harness. In rear-facing seats, the harness should be at or below the child's shoulders and in forward-facing seats at or above the shoulders. The more slots there are, the better the seat can accommodate a child's growth. Look for the most slots in a seat with a high weight capacity.

In the rear-facing mode, some convertible seats have as many as five reclining positions. Multiple adjustments can keep smaller children correctly inclined on vehicle seats with different cushion angles, and they can come in handy when your child naps in the car. The seat should be adjusted at the proper angle (as close to 45 degrees as possible) in order to keep your baby's airway clear.

Today's car seats cater to every possible taste: plain colors, plaids, animal and paw-print motifs, and patriotic red, white, and blue. Babies are messy, so washable fabric is a plus. Some upholstery requires hand-washing and line drying. And removing some upholstery requires extensive dismantling, so check the instructions before you buy. Leather may look good, but it can become hot in the sun and cold in winter.

Add-on seat covers (boots), thicker padding, and adjustable head-support cushions are available for some seats. Add-ons can make the seat more comfortable. But buy them only if they're made for your specific seat by the same maker and have been tested with the seat in government crash tests.

Many convertible and booster seats come with cup holder and snack trays. Some infant seats have elastic side pockets for bottles, snacks, or toys. They're nice but not necessary, especially if your car has cup holders in the back seat.

These allow a child seat to be attached to the frame of a shopping cart. The American Academy of Pediatrics doesn't recommend this, and neither do we.