Preterm babies do not always need to have an MRI before discharge from the hospital, depending on the baby’s condition. If the baby’s birth weight is greater than 2kg, he/she cries loudly after birth, breathes well, feeds on his/her own, there is no intrauterine hypoxia, and there are no emergencies during birth, MRI is usually not necessary. If the baby’s birth weight is less than 2kg, or there is intrauterine distress, asphyxia during birth, no spontaneous breathing after birth, or even ventilator-assisted ventilation, etc., it is very easy to cause intracranial hemorrhage in preterm babies, abnormal signals of cerebral white matter, or hypoxic-ischemic encephalopathy, in which case the cranial MRI should be performed promptly to clarify whether there is any damage to the brain. MRI has the characteristics of non-invasive, non-radiation, for brain damage, diagnostic specificity is higher, accuracy is also good, only a little longer examination time, parents do not need to worry too much, not all preterm infants need to be discharged from the hospital to do MRI, according to their own situation to follow the doctor’s instructions for examination.