When you're shopping for a crib, you'll also need to choose a mattress, which typically is sold separately.
Don't underestimate this purchase; a mattress is as important as the crib. After all, your baby will spend a lot of time snoozing--up to 18 hours a day initially--so it's essential to select the best-quality mattress you can afford. Size and firmness are the main concerns. If a mattress is too small, it can leave gaps in the crib that could trap and endanger your baby. If a mattress is too soft, it can conform to your baby's shape, causing a risk of suffocation or Sudden Infant Death Syndrome (SIDS).
There are two general types of crib mattresses: foam and innerspring. Either is an acceptable choice. Both types--if they're good quality--will keep their shape well and provide excellent support for infants and toddlers. There are differences, though. Foam--made from polyurethane--tends to be lighter. The densest foam mattress usually weighs 7 to 8 pounds, compared with the 15 to 23 pounds of an innerspring mattress. So, although you're probably just lifting a corner at a time, changing your baby's sheets may be easier with a foam unit. Foam is also less springy and therefore less likely to encourage your child to use the mattress as a trampoline. Still, innerspring mattresses remain the most popular because they are what most adults sleep on in the U.S.
Mattresses are a "blind" item, meaning that almost everything that matters is on the inside, where you can't see it. A crib mattress can feel great in the store, but begin to falter once your baby starts to use it. We've learned that you can't depend on sales staff, even at reputable retail outlets, to give you accurate information. One salesperson told us, quite convincingly, that innerspring mattresses were better than foam because foam tends to "break down" after 18 months. Twenty-five years ago that may have been true, but not anymore. "A top-quality foam crib mattress will hold up just as long as an innerspring crib mattress, with normal use," says Dennis Schuetz, director of marketing for Colgate Kids, a manufacturer of juvenile mattresses, in Atlanta. That's because foam crib mattresses have become much more durable.
The best foam mattresses
If you decide to go with foam because it's lightweight, density is the most significant sign of quality.
Dense foam. The best foam mattresses are firm and heavy and resilient--they bounce back quickly when you squeeze them in the center and the edges with both hands. To assess foam quality, compare the weight of different models. That's not always easy to do in a store, but if you're able to lift several mattresses, do it. In general, the heavier the foam mattress, the denser (and better) the foam. You can give the mattress a squeeze test in the center by pressing your palms into both sides at once. A dense mattress won't allow you to press very far.
The best innerspring mattresses
If you decide on an innerspring mattress, follow this general rule: the more layers and the better quality of those layers, the better the mattress.
High coil count and low steel gauge. "Coil count," the number of springs or steel coils a mattress contains, is a popular marketing point. But a generous coil count doesn't always mean a firmer mattress. The cheapest innerspring baby mattresses may have fewer than 80 coils and more expensive models may have more than 280 coils, but a model with 150 coils could be firmer than one with 200. How? The gauge of steel in those 150 coils may be thicker than the steel in the 200-coil mattress. Steel gauge for mattress coils ranges from 12.5 to 19; the lower the number, the thicker the steel. Thicker is stronger. So look for a moderate to high coil count--135 to 150 coils is a good midrange--and a lower coil steel gauge, 15.5 or below.
Coir fiber or wrap pad as the insulator pad. On top of the coils is an insulator pad that keeps the coils from poking through a mattress' cushioning layers (see below) and bothering your baby. The best insulator pad is made from coir fiber--shredded and woven coconut shell--but fiber wrap pad, also called "rag" or "shoddy" pad, which is made from miscellaneous and pressed scraps of cloth, is also good. Coir fiber is more expensive than fiber wrap pad, but either works well. The lowest quality insulator pad is made from woven polyester. Because it tends to form pockets over time, becoming concave where most of the baby's weight rests, it's less durable.
Foam or cotton cushioning layers. The next layer in the mattress sandwich is the cushioning, which may be made of foam, cotton, or polyester. Foam and cotton are signs of quality, though they contribute to the price. Polyester, which is less expensive and increasingly pervasive because the cost of foam to manufacturers has been rising, isn't ideal because of its tendency to form pockets.
Border rods. They go around the perimeter of the mattress top and bottom, and are the thickest pieces of steel a mattress contains. Don't buy innerspring mattresses that don't have border rods. Border rods provide extra firmness, durability, and edge support so a mattress won't sag when your baby stands or walks near the edge. Consider border rods a must-have.
Cover. Encasing the entire mattress is a fabric or vinyl cover. Fabric breathes more than vinyl, but ventilation holes in a vinyl covering help air circulate. The more vents the better. A thicker or layered vinyl covering better resists leaks, stains, punctures, and tears, so go with vinyl over fabric. Look for at least a triple laminated ("3-ply") covering, which will give a mattress a tougher shell, adding to its longevity. Unlike a cloth cover, vinyl also acts as a barrier to dust mites.
Check for firmness. Buy the firmest, heaviest mattress you can find. Don't worry that it may feel too firm. "If it feels good to you, it's too soft for your baby," Schuetz says. Most babies will get used to sleeping on anything after a day or two. Press on the mattress in the center and at the edges. It should snap back readily and should not conform to the shape of your hand.
Test the fit. By law, all full-size crib mattresses must be at least 27 1/4 inches by 51 5/8 inches and no more than six inches thick. Shop in a store that displays crib mattresses and check the fit before you buy by pairing the mattress with the crib you choose. If you can squeeze more than two fingers between the mattress and the crib, the mattress is too small.
Know quality--then find it. Don't buy a mattress from a manufacturer or a retailer that doesn't reveal, with in-store information or displays, what the mattress is made of, or the components of each layer.
Don't worry about warranties. Some mattresses offer a one-year, a seven-year, or even a lifetime warranty. Don't be swayed by a long warranty, and don't pay extra for a mattress with a warranty. "Warranties are mostly a marketing tool to entice the consumer to spend more," says Schuetz. In general, you can expect any quality crib mattress to last as long as you're going to use it, provided that the cover hasn't become ripped or torn and that it's been used properly (for sleeping, not for toddler tumbling).
Should you buy a convertible mattress? If you're planning to convert your baby's crib to a toddler bed, "dual firmness" convertible mattresses are available at the top end (in the $260 range). These mattresses are designed to go the distance. They're extra firm for infants on one side, and they're cushier, with standard foam or springy, "viscoelastic" memory foam for toddlers on the other. (You can flip the mattress after your baby's first birthday, when the risk of SIDS decreases.) But put this added feature in the "not necessary" category. Your baby will still be happy with a firm mattress when he becomes a toddler. If he's exposed to a more forgiving mattress, he probably won't want to go back. So if you buy a dual-firmness mattress, be sure not to flip it too soon.
Is a waterproof mattress cover necessary? It's a good idea, even if the mattress you select is leak proof, because a mattress cover will make your baby's sleeping surface cozier. Without it, the chill of the mattress's vinyl cover is apt to come through, no matter what the thread count is of the fitted sheet. A waterproof cover will protect the surface of your baby's mattress from diaper leaks, absorb the liquid, and wick it away from your baby's skin. But it's still a good idea to wipe down a crib mattress with a damp cloth and mild soap any time the mattress gets wet or soiled.
Do you need an antimicrobial cover? Some mattresses are sold with a special antimicrobial additive that's mixed in at the factory when the vinyl cover is in a liquid state. An antimicrobial mattress cover will slow the growth of mold and bacteria, but it won't prevent it altogether. Do you need this trendy feature? Definitely not. To prevent microbe growth, keep your baby's mattress clean by wiping it down after any accidents with soap and water. When you're done with the mattress, put it in a snug-fitting crib mattress storage bag, preferably one you can see through (light inhibits bacterial growth). Then stow the mattress in a cool, dry place--in other words, not a damp basement or stuffy attic.
The major brands of foam and innerspring crib mattresses are, in alphabetical order: Colgate (www.colgatekids.com), Da Vinci (available at retailers and e-tailers such as www.babyuniverse.com), Dream on Me (www.dreamonme-usa.com), Kolcraft (www.kolcraft.com, which offers a number of brands, including Baby Prestige, Pediatric, and Sealy), Moonlight Slumber (www.moonlightslumber.com), and Simmons Kids (www.simmonskids.com).
You don't have to spend a fortune to get a good-quality mattress, but don't skimp, either. A mattress that costs between $90 and $200 will generally serve your baby well. Prices for foam and innerspring mattress are comparable, ranging from $50 to $530 (for mattress constructed with tufted organic cotton), but you can't go wrong if you spend in the range of $90 to $200. Low-priced models (less than $90) tend to be mushy and flimsy. Higher-priced models tend to be firmer, and therefore safer.
With an innerspring, the number of layers, what each component is made of, and the quality of the covering add to the price and increase comfort. The cheapest foam and innerspring mattresses have thin vinyl coverings and edgings that can tear, crack, and dry out over time. As prices go up, coverings become thick, puncture-resistant, reinforced double or triple laminates. The weight also tends to increase because the innerspring mattress contains more or better-gauge steel and better-quality cushioning while the foam mattress is made of denser, better-quality foam. Reversibility, the presence of ventilators, and thickness are factors that differentiate models.