Fetal Thrombotic Vasculopathy in the Placenta: Cerebral Thrombi and Infarcts, Coagulopathies, and Cerebral Palsy

When thrombi form in the fetal circulation of the placenta, they produce a clustering of fibrotic villi, a state termed fetal thrombotic vasculopathy (FTV). This has been related to serious neonatal damage, in particular brain injury. One report found FTV in 11 of 15 cerebral palsy patients. The present study estimated the prevalence of placental FTV in a series of 84 perinatal autopsies and attempted to determine whether it is a valid marker of thrombotic lesions in infants who survive. The autopsies were performed over a 3-year period.Placental lesions of FTV were found in 16 autopsies (19 percent of the total). In all stillbirths, the changes had clearly been present for at least 48 hours. FTV was extensive in all affected babies. One each of the eight mothers tested had combined protein S/antithrombin III deficiency, combined activated protein C resistance/protein S deficiency, an elevated cardiolipin antibody titer, and an elevated antinuclear antibody titer. Another woman with normal coagulation findings had had episodes of deep vein thrombosis and was given heparin during her pregnancy. The only mother tested for the methylenetetrahydrofolate reductase gene mutation was positive. Thrombi in vessels of the brain, kidneys, and lungs exhibited organization, fibrosis, or breakdown. Cerebral infarcts were associated with necrosis, gliosis, and in some cases calcifications. None of the fetuses and infants without FTV had visceral thrombi.The presence of placental FTV signifies a significant risk that thrombi are present in the fetus. They may cause significant neonatal injury, especially cerebral palsy, or perinatal death. It may well be that strokes are a major cause of brain damage for the fetus as they are in adults. Maternal coagulopathy is a significant factor in some of these cases, and this association deserves more study.Hum Pathol 1999;30:759–769