There are several common causes of hypoglycemia in newborns: 1. It is common in premature babies, mainly related to insufficient storage of liver glycogen, the younger the gestational age, the more serious it is, and often there is also low enzyme activity in the gluconeogenesis pathway. 2. The presence of congenital heart disease, infection-induced sepsis or being in hypothermia in newborns can lead to hypoglycemia due to insufficient intake of calories and increased glucose utilization. 3. The mother has diabetes and hyperinsulinemia, and the fetus is prone to neonatal hypoglycemia after birth due to the sudden interruption of blood sugar supply. 4. Genetic metabolic diseases and endocrine defects can easily lead to neonatal hypoglycemia, and such hypoglycemia is prone to persistent hypoglycemia due to the persistence of the disease itself.