Every mother wants what is best for her baby. Deciding on the most comfortable and supportive baby crib mattress is an often overlooked factor when preparing the nursery for a new arrival. Although the baby crib mattress needs a certain amount of consideration, the basic choice is between two types of mattress; innerspring and foam.Innerspring and foam mattresses are quite different, familiarize yourself with the differences. The innerspring mattress is heavier, much more complex, and has more bounce to it. Remember that your baby crib mattress will be used for about a year, and perhaps even longer if the crib can convert to a small bed.A springy mattress might be comfortable and spread your child's weight evenly, but it also makes a great trampoline.Essentially, an innerspring baby crib mattress is made through combining layers of steel coils, insulation and foam. It is actually the weight of the steel coils that determine how soft or how firm the mattress will be. Heavier coils provide a higher quality mattress. A firm, durable and safe mattress will be well worth the additional expense. Simple in design, a foam baby crib mattress can provide the same support as a innerspring mattress. The denser the foam, the better the quality is going to be. Prod the mattress to assess it before you buy. Ideally, you cannot feel the other side, and the surface of the mattress should rebound quickly when you let go.Firmness is essential in a baby's bed. Especially when an infant is very small, it is the baby crib mattress which supports it's delicate body and developing back. The consideration you put into choosing a baby mattress should take into account the density, whether it be the weight and number of coils or the density of the foam layer.Weather choosing a innerspring or foam mattress, more importantly is a tight fit in the crib frame. This will take a little work on your part, as most cribs and mattresses are purchased separately. Measure carefully before you buy either one.Weather you choose a foam or a innerspring baby crib mattress, either type can work quite well for your baby. More importantly is the quality. Consider the higher quality mattress as a better investment. It will be firmer, better for your baby, and last longer.