780: The progressive involvement of placenta in case of chorionamnionitis according to Triple I classification

Abstract

The objective of the study was to verify the appearance of signs of suspected Triple I and the progressive involvement of placenta according to Redline classification of chorionamnionitis (CHA) and to understand the impact of CHA on maternal and neonatal outcome A retrospective cohort study of histological placental analysis obtained after term pregnancies between 2014-2017 at Carate Brianza Hospital, University of Milano-Bicocca. Included were all cases of HCA. The diagnosis of maternal fever (T°) and suspected intraamniotic inflammation, infection or both was made according to Triple I classification (IAI). Maternal adverse outcomes were defined as postpartum haemorrhage, endometritis or composite bad outcome (Mbad) including fever after hospital discharge and/or prolonged antibiotic therapy. Neonatal adverse outcomes were defined as asphyxia, positive blood culture, high CRP or composite bad outcome (Nbad) including admission to NICU and/or prolonged antibiotic therapy. Histological CHA was stadiated for severity according to Redline classification. Analyses were conducted by SPSS® 24.0; p-value <0.05 was considered significant Among 6,962 deliveries, 1,314 placentas of which 1,122 at term, were analysed, 32.4 % due to signs of IAI in labour . 339 of placentas had HCA and 133 (39.2%) of them had a whole inflammatory involvement (PLw). The presence of T° plus all 3 other clinical signs of IAI (all T°) was significantly related to stage 1 (p<0.01), stage 2 (p<0.05) of maternal inflammatory placental involvement (PLm) moreover to stage 1 (p<0.01), stage 2 (p<0.02), stage 3 (p<0.01) of fetal inflammatory placental involvement (PLf). PLw was significantly related to all T° (p<0.028). Signs of IAI plus HCA was related at univariate and multivariate analysis to Mbad (OR 7.12, p < 0.008). Endometritis (p < 0.03) and Mbad (p < 0.02) were related to PLw. High CRP (p < 0.001) and positive blood neonatal culture (p < 0.001) were related to PLf The progressive appearance of more clinical sign of IAI during labour at term is related to a gradual severe involvement of the placenta leading to HCA. Maternal and/or neonatal outcomes are more likely to be adverse when this diade is present: clinical signs of IAI and HCA.