Your baby's health and safety depend on having an appropriate mattress. While shaped crib mattresses often come included with their respective cribs, if this isn't the case for you use a tape measure to ensure it fits seamlessly without gaps or other irregularities.
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Crib mattresses must adhere to stringent safety standards that help to reduce the risk of Sudden Infant Death Syndrome (SIDS). In addition, they come equipped with waterproof covers.
Size
Selecting an ideal crib mattress size is an important task for new parents. Babies will spend most of their first year sleeping in their cribs, so they should feel at ease while resting there. There are various factors to keep in mind, including size, firmness and breathability when making this important choice.
A standard crib mattress size should measure 27 1/4 inches wide by 51 1/4 inches long, and be less than 6 inches thick to reduce entrapment and suffocation risks. This recommendation from the Consumer Product Safety Commission helps keep babies safe.
Small gaps between a crib mattress and wall aren't dangerous, but any larger gap could potentially harm a child. Therefore, when purchasing a crib mattress it is vitally important that one consults manufacturer specifications rather than shipping measurements when purchasing. It should also be remembered that different shaped cribs require mattresses specially sized to their shape – hence why most bassinets come equipped with their own crib-sized mattress that's perfectly fitted.
Firmness
Firm crib mattresses can help reduce the risk of suffocation. Soft mattresses have been linked with many infant deaths and increase chances of Sudden Infant Death Syndrome (SIDS), so parents should make sure their baby's mattress is firm rather than too soft.
Test the firmness of a crib mattress by inserting two fingers between its edge and the side of the crib – gaps should not exceed one inch in width.
Steel gauge, or the thickness of coil springs, plays an integral part in determining the firmness of a crib mattress. Greater numbers signify thicker coil springs and, thus, firmer mattresses. Some innerspring crib mattresses feature border rods to further add firmness; foam crib mattresses are often made from polyurethane foam for greater lightness and budget-friendliness compared to innerspring alternatives.
Reversible
Reversible crib mattresses are an excellent solution for parents looking for their infant to sleep on both soft and firm surfaces at various stages of development. It is important to remember that any such mattress must fit snugly without gaps larger than two fingers to reduce risk of entrapment or suffocation for infants.
A breathable mattress will not only ensure proper airflow, but will also prevent overheating and sleep disruptions that increase the risk of SIDS. Furthermore, it will protect your child against dust mites, mould, and allergies.
Drs. Odom and Levy agree that the best breathable crib mattresses include organic cotton covers with nontoxic filling materials; both recommend the Newton Original as their top pick. Its core is composed of food-grade polymer that contains 90% air for superior breathability; off-gassing is prohibited and it contains no phthalates; while its quilted covering features 3D spacer fabric to promote airflow while insulating against temperature variations for comfort across temperature extremes.
Safety
At the forefront of creating a nursery is ensuring their safe sleep space, meaning finding a mattress with ideal dimensions and firmness that fits securely within their crib without gaps or holes.
Babies require a firm surface to support their heads and decrease the risk of suffocation. Soft mattresses increase the risk of sudden infant death syndrome (SIDS).
Consumer Product Safety Commission (CPSC) regulations for crib mattress manufacturers provide strict guidelines for size and fit, such as interior dimensions of standard crib mattresses being 28" inches wide by 52 3/8" inches long with no more than 1 inch gap between it and the sides of the crib. To make sure your crib mattress fits perfectly, purchasing it from an actual store allows you to check measurements and firmness directly, and additionally an anti-mildew cover may help protect from mold or mildew growth.