The difference between neonatal hypoxic-ischemic encephalopathy and brain injury is that hypoxia and ischemia cause brain injury, but brain injury does not have to be caused only by hypoxia and ischemia, it can also be caused by other reasons. Neonatal hypoxic-ischemic encephalopathy is a newborn or fetal brain injury caused by partial or complete oxygen deprivation due to perinatal asphyxia, which results in decreased or suspended blood flow to the brain. However, there are many causes of neonatal brain injury, besides ischemia and hypoxia, there are also causes such as before, during and after birth. 1. Before birth: It is mainly caused by maternal factors, such as high maternal age, preterm miscarriage, high blood pressure, diabetes, viral infections, etc. during pregnancy. 2. At birth: the most common is asphyxia and hypoxia at birth, which leads to insufficient supply of blood vessels to the brain, resulting in brain damage. 3. After birth: premature babies, low birth weight babies, hyperbilirubinemia, etc.