Histological Inflammatory Responses in the Placenta and Early Neonatal Brain Injury

Abstract

We investigated the relationship between the severity of histological inflammatory responses in the placenta, chorionic plate, and umbilical cord in conjunction with the intraventricular hemorrhage (IVH) risk in premature infants. Clinical data were prospectively collected for 287 consecutive premature neonates born before 32 completed weeks of gestation and admitted to the level III neonatal intensive care unit of the Department of Pediatrics at Padua University from January 1999 to December 2004. Placental histology for histological chorioamnionitis (HCA) was graded and scored according to Redline and others. The diagnosis of IVH (grades I-IV) was graded according to Volpe's classification. Among the placentas of the 287 preterm examined infants, 68 (23.6%) were diagnosed with acute HCA. Overall incidence of IVH was 11.8%. Of 68 preterm neonates with HCA, 11 developed IVH (16.1%). Maternal HCA at the higher grades and stages increased the risk of IVH: 7 (64%) of the 11 preterm infants with maternal HCA grade 3 developed IVH (RR; 95% CI 2.05; 1.1-3.6) and 8 (73%) of the 11 preterm neonates with stage 3 developed IVH (RR; 95% CI 1.59; 1.0-2.5). Conversely, fetal inflammation was not associated with an increased risk of IVH. In conclusion, the IVH risk in preterm infants at less than 32 gestation weeks is significantly associated with severe grade and stage maternal HCA inflammatory scores.