Impact of villitis of unknown etiology and adverse acute neonatal outcomes in Eastern Ontario

Introduction: Villitis of unknown etiology (VUE) is a histopathological lesion associated with adverse neonatal outcomes. We seek to define the obscure relationship between the severity and distribution of VUE and adverse neonatal outcomes.

Methods: A retrospective chart review was conducted of pathologic findings from singleton placentas diagnosed with VUE between 2013 and 2019. Control placentas were matched 1:1 for gestational age and presence/absence of fetal IUGR. Neonatal outcomes of interest included: newborn resuscitation, NICU admission, Apgar scores and cord blood acidosis. Odds ratio and 95 % confidence intervals were calculated with controls as the reference.

Results: 452 placentas were included. 35 % of pregnancies were complicated by IUGR. When analyzed by severity (low-grade: OR = 4.75 [2.86-8.14]; high-grade: OR = 4.76 [2.71-8.79]) and distribution (focal: OR = 5.24 [2.87-10.17]; multifocal: OR = 4.90 [2.90-8.59]), VUE was significantly associated with need for newborn resuscitation. No other neonatal outcomes of interest were significantly associated with VUE diagnosis.

Discussion: We determined a statistically significant association between VUE severity and distribution and the need for newborn resuscitation. VUE lesions were not associated with any additional neonatal outcomes of interest. Further studies with larger sample sizes are required to confirm these associations for obstetric and neonatal case management.