The best option for a newborn is a double-sided mattress, that is, a mattress with a different degree of firmness of the sides. This is achieved by using appropriate materials. The hard (orthopedic) side of such mattresses is usually formed from coconut flakes, the softer one is created from latex foam, polyurethane foam, holofiber.
Newborn mattressFor the first six months of life, the child must sleep on the hard side. This is necessary in order for the natural curves and reliefs of the newborn's back to form. These processes are usually completed by the age of 6 months, after which it is advisable to turn the mattress so that the child sleeps on the softer side.
The standard length of a crib is 120 cm and a width of 60 cm. And baby mattresses are usually in accordance with these dimensions. In extreme cases, it is permissible that it be slightly smaller, however, the gap between the mattress and the crib should not be more than 3 - 4 cm, otherwise the leg or handle will fall into this void and the child will be injured. It is impossible for the mattress to be larger than the bed, because in this case it will not lie evenly, forming deflections or bends, and this is already fraught with curvature of the spine.
The mattress must be covered with oilcloth or a special waterproof mattress topper. As an oilcloth, you can use a waterproof, as well as medical or quilted (with foam filling) oilcloth. Each of the options is acceptable. The cheapest of them is medical oilcloth. It is made on a fabric basis and is quite comfortable.
Mattresses need to be turned over periodically. This ensures normal air access to both sides, prevents dust accumulation and caking of the filler. Moreover, it is necessary to change not only the sides of the mattress, but also its foot and headboard. For mattresses with different side rigidity, the footboard and headboard should be changed once every 3 months, and turned over from side to side in accordance with the age periods.