Placental pathology and neonatal thrombocytopenia: lesion type is associated with increased risk

To investigate the association between thrombocytopenia and placental lesions.Cases included singleton infants admitted to the intensive care unit (2005 to 2010) with platelet counts100 000 μl(-1). We selected a contemporaneous control group matched for gestational age: 49 cases and 63 controls. The frequency of thrombosis in fetal vessels, fetal thrombotic vasculopathy, acute chorioamnionitis, chronic villitis, infarcts, hematomas, cord insertion and increased circulating nucleated red blood cells were identified on retrospective review of placental histology. Logistic regression models were used to test for associations.Placental lesions associated with poor maternal perfusion (odds ratio (OR) 3.36, 95% confidence interval (CI) 1.38, 8.15) or affecting fetal vasculature (OR 2.75, 95% CI 1.05, 7.23), but not inflammation, were associated with thrombocytopenia. A Pearson Chi-Square Test for Independence for fetal and maternal lesions indicated that the two are independent factors.Poor maternal perfusion and fetal vascular lesions are independently associated with thrombocytopenia in the newborn.