Placental pathology in relation to stillbirth and neonatal outcome in an extremely preterm population: a prospective cohort study

ObjectiveTo study associations between placental histopathology and stillbirth as well as neonatal outcome in a population born extremely preterm. DesignProspective cohort study. SettingStockholm, Sweden. Population167 infants born <27 gestational weeks during 2004-2007. MethodsOne senior perinatal pathologist, blinded to outcome data, evaluated all placental slides. Main outcome measuresIntrauterine fetal death, small-for-gestational age, major neonatal morbidity (intraventricular hemorrhage grade 3, retinopathy of prematurity grade 3, necrotizing enterocolitis, cystic periventricular leukomalacia or severe bronchopulmonary dysplasia) and neonatal mortality. Additional outcome variables were Apgar score at 5min, sepsis, and treated patent ductus arteriosus. ResultsAccelerated villous maturation was associated with a decreased risk for Apgar score <7 at 5min (p=0.041). Fetal thrombosis and low placental weight were associated with an increased risk for both intrauterine fetal death (p<0.001 and p=0.011, respectively) and small-for-gestational age (p<0.001 and p<0.001, respectively). ConclusionPlacental histology may have prognostic value as it appears to be associated with intrauterine fetal death, as well as with being small-for-gestational age and assignment of a low Apgar score at birth.