Newborn babies suddenly cry during sleep may be due to environmental, dietary, disease and other factors. 1. Environmental factors: if the environment is too noisy, suddenly a huge movement will scare the baby, or due to the environment temperature is too high, resulting in the baby uncomfortable, etc., will make the baby appear to cry. 2. Dietary factors: if the baby formula brewing ratio is not right, eat too much, etc. lead to the baby’s gastrointestinal function disorders, indigestion, can cause stomach cramps, abdominal pain, abdominal distension and other symptoms, will lead to the baby in the sleep of the sudden cry. 3. Disease factors: such as the lack of vitamin D3, will make the baby’s nervous excitability increase, so that the symptoms of crying. If the baby suddenly colic, the pain will cause the baby to cry. Newborns suddenly cry in their sleep may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, give targeted treatment or treatment.