There are many reasons why babies cry and do not sleep during the month. In addition to normal physiological reasons, other factors such as growth factors, environmental factors and pathological factors should also be taken into consideration. 1. Physiological factors: the baby’s nervous system and digestive system are not yet fully developed, the nerves are too excited or do not help the newborn to expel the gas in the stomach before going to bed, may lead to the baby crying and unable to sleep. 2. Growth factors: the growth of newborns’ bones and muscles will make newborns feel uncomfortable, thus crying and affecting sleep. Newborns grow faster, need a lot of trace elements and vitamins, if the lack of calcium or vitamin D, there will be babies cry and do not sleep. 3. Environmental factors: newborns are more sensitive to external stimuli, sound, light, cold, heat and other stimuli, will make newborns feel uncomfortable and crying, so provide a comfortable and quiet resting environment for newborns, is conducive to newborns sleep. 4. Pathological factors: the newborn immune system is not yet fully developed, easily infected with viruses and bacteria, so when the newborn cries and does not sleep, you should also pay attention to whether there is a fever, respiratory distress and other symptoms, and promptly sent to the hospital for examination. It should be noted whether breast milk is sufficient, babies will also cry when they are hungry. Congenital diseases of newborns, such as congenital heart disease, pulmonary isolation, etc. can also cause infants to cry more than once, and should be observed and seek medical attention promptly.