The placenta in infants >36 weeks gestation with neonatal encephalopathy: a case control study

OBJECTIVE: To determine placental characteristics associated with neonatal encephalopathy (NE) and correlate these with short- and long-term neurodevelopmental outcome. DESIGN: Case/control study. SETTING: Neonatal Intensive Care Unit, Rotunda Hospital, Dublin, Ireland. PATIENTS: Newborns ≥36 weeks gestation, with NE (cases). Healthy term newborns (controls). INTERVENTIONS: Placental pathology was obtained from the official placental report. Brain MRI was blindly reviewed. Children were assessed using a variety of standardised assessments. Data were analysed using multinomial logistic regression analysis. MAIN OUTCOME MEASURES: RRR for grade of encephalopathy. OR for neurodevelopmental outcome. RESULTS: Placental reports were available on 141 cases (76 grade 1; 46 grade 2; 19 grade 3) and 309 control infants. Meconium phagocytosis, haemorrhage, raised placental to birth weight ratio and/or markers of infection/inflammation were independently associated with NE and showed a synergistic effect, when combined, for short- and long-term impairments. CONCLUSIONS: Evaluation of the mechanisms leading to the placental characteristics identified may help to characterise the causal pathway of NE.