Abstract
INTRODUCTION: Specific fetal heart rate (FHR) patterns are associated with fetal compromise. Several placental histopathological findings are associated with neonatal morbidity and adverse neurodevelopment. The relationships between intrapartum FHR patterns and placental histopathology in infants with hypoxic-ischemic encephalopathy (HIE) remain uncertain. This study hypothesized that in infants with HIE, placental histopathology findings are related to abnormal FHR patterns. MATERIAL AND METHODS: This was an observational study performed on a historical cohort from a single tertiary neonatal intensive care unit. Infants were born at ≥36 weeks' gestation with moderate or severe HIE between September 2006 and December 2021. Placental histopathology was assessed by a perinatal pathologist using the Amsterdam Working Group Criteria. FHR, recorded from intrapartum cardiotocography (CTG) was assessed by an obstetrician using a structured proforma. Assessors were blinded to clinical course and outcomes. Duration and type of FHR abnormality were compared across categories of placental histopathology findings. RESULTS: Fifty infants with moderate or severe HIE (with complete data relating to intrapartum CTG and placental histopathology) were included. Increased duration of FHR abnormality was associated with the presence of histological chorioamnionitis (HCA) (p = 0.013) but not with other placental histopathological lesions. There was no evidence of associations between placental histopathology findings and specific FHR features on intrapartum CTG. CONCLUSIONS: This study demonstrates an association between HCA and increased duration of CTG abnormality in infants with moderate or severe HIE. Intrapartum CTG alone is limited in its ability to identify the presence or absence of placental histopathology. Multimodal intrapartum assessment, such as CTG with placental NIRs or Doppler assessment, may improve the maternal-placental-fetal triad assessment. This could lead to improved intrapartum risk stratification and infant outcomes. Future research should investigate the utility of multimodal assessment to improve risk stratification in labor.