Shopping for a mattress is easy when you're buying for an adult. You have your pick of options - soft or firm, stationary or adjustable, memory foam or coil spring - so you're free to buy what feels good.
But the things that make mattresses comfortable for adults can be deadly for babies. You may want something soft, but such a mattress could very well pose a suffocation risk. When shopping for a crib mattress, you can't rely just on what feels good to you.

There are only a few things to check for when buying a baby mattress, but these factors are nonetheless very important to examine when shopping. Here's what to look for so you ultimately find the best crib mattress for your baby.

The importance of a good mattress

One commonly cited statistic is that infants spend about 16 hours a day sleeping. Most of that time will be on a crib mattress, making this one of the most important nursery purchases you'll make. 

The right mattress keeps your baby comfortable, reduces fussiness and helps you get a good night's sleep. A firm baby mattress also reduces the likelihood of SIDS, according to the National Institute of Child Health and Human Development, and supports your child's growing bones.

Unlike mattresses for adults or children, those made for infants are designed to fit snugly inside a crib. This is why it's important to buy one specifically for infants, rather than buying, say, a twin-size mattress and hoping it'll fit.

Most mattresses last approximately three years, so you shouldn't have to replace it until after your child transitions to a toddler bed. That said, go ahead and buy a new one if you see signs of wear and tear.
Now that you know why a good crib mattress is important, let's talk about finding the specific type that's right for you and your baby.

Choosing the right type of crib mattress

While you don't need to purchase a mattress until your third trimester, it's a good idea to start researching early. Mattress types are named after the material inside them, so they're very easy to identify.
Foam

This is the cheapest, most basic crib mattress. This kind is less durable than other types, so it's not great for the long term. However, they're also the lightest option, making them perfect for portable cribs.

Foam crib mattresses are usually between three and six inches thick and made of one or more blocks of foam. This foam is made of multiple possible materials, including polyurethane, latex and bamboo fiber. You'll want to check the material type when shopping; polyurethane is cheaper but loses its shape easily, while latex is more expensive yet more durable.

Memory foam

Like the version for adults, memory foam mattresses mold to your baby's shape. They'll slowly spring back to their original form when your baby isn't on it. Keep in mind that many memory foam mattresses have a coiled spring core with a layer of memory foam on top so they can't be flipped over.

The softness of a memory foam mattress adjusts to your baby's body temperature as well, softening up when it comes in contact with baby's warmth. What's more, your infant's weight reduces air circulation in the mattress, making it feel warmer. This is great for cold winters but can get uncomfortable in the summer.

Coil spring/innerspring

This mattress type is named for the steel coils that make up the core. Each coil is connected by a steel frame. While coil spring mattresses are very supportive and durable, they're also much heavier than foam.

Like with foam, you'll want to do a little research when choosing a coil spring mattress. Brands will often advertise their coil count, but this doesn't necessarily mean a firmer (and therefore safer) option. What's more important is the gauge (or thickness) of the steel used. A lower gauge means thicker steel, making for a more supportive mattress.

If you go with a coil spring, be certain to avoid cheap versions. They squeak with every movement, which will certainly keep you up at night.

Pocket spring

These mattresses also use steel coils, but they aren't connected by a frame. Rather, each one is sewn into a pocket of material, allowing it to move independently of the others. This has an effect similar to a memory foam mattress, as each spring will compress according to the amount of weight placed on it.

Overall, pocket spring mattresses provide great support and last a very long time, but they're also one of the most expensive options.

Natural/organic materials

These crib mattresses are made from natural materials and fibers such as coconut fiber, natural latex, organic cotton and untreated wool. The latter is a natural flame retardant and dust mite resistant.

Natural mattresses are gentle on allergies and chemical free. They also tend to be quite durable. However, loose regulations mean these mattresses may only contain a small amount of the natural material. Ask other moms for recommendations, if you want to go this route.

Choosing the best crib mattress

Selecting the perfect mattress and making the right choice for your baby depends on your needs and budget, but it's good to keep in mind these three tips:

1. Look for reviews from other moms.

2. Make sure the mattress is firm, flame retardant and has air vents.

3. Choose a mattress light enough for you to carry.