Due to developmental immaturity of the central nervous system, effects of an adverse intrauterine environment and need for intensive care postnatally, preterm infants are at high risk of sustaining brain injury in the perinatal period. Infants who suffer brain injury in the perinatal period are at risk for long-term neurodevelopmental sequelae. Clinical and experimental data supports a significant role for inflammatory mediators in the pathophysiology of perinatal brain injury. Abnormalities in coagulation proteins in the sick preterm newborn may accentuate the risk for intraventricular hemorrhage. Polymorphisms in TNFα, IL-1β, IL-4, IL-6 and IL-10 as well as mutations in coagulation proteins have been investigated as potential candidate genes to modify risk and or severity of perinatal brain injury. Preliminary evidence suggests a role for cytokine genes as risk modifiers for IVH and PVL.