Different gestational ages and changing vulnerability of the premature brain.

In recent decades, there has been a general increase in survival rates of preterm and low birth weight infants, but this overall decrease in perinatal mortality has not been accompanied by a decrease in long-term physical and mental disability. In order to reduce the long-term sequelae of prematurity and to establish preventive measures, it is important to identify risk factors since the main determinant of specific vulnerability to different types of lesions is gestational age. The regional tissue vulnerability at a given gestational age is probably determined by the local metabolic requirements together with specific cell characteristics and their level of maturation. In this article, we discuss the most common neonatal cerebral lesions (cerebellar haemorrhage, germinal matrix intraventricular haemorrhage, periventricular leukomalacia, arterial ischaemic stroke, cerebral vein sinus thrombosis and hypoxic-ischaemic encephalopathy) related to the gestational age-dependent vulnerability of the premature brain.