Newborns can lie on their backs for more than 2 days after birth, because the cervical vertebrae of newborns are able to bear the weight of the head at this time, but it is not recommended to lie on their backs for a long time. Lie down on the newborn has certain benefits, can help the newborn exercise both lungs breathing as well as get enough sense of security, but a long time lying down may affect the development of the cervical spine, and even fall asleep after blocking the mouth and nose of the risk, you can be in the parent’s supervision of a short period of time lying on the ground, each time 2 ~ 3 minutes. Many newborns may experience colic within 3 months, and parents will let their newborns lie on their backs to relieve it. It is recommended not to take this measure, which is not conducive to the physical development of newborns.