Fetal thrombotic vasculopathy in the placenta: cerebral thrombi and infarcts, coagulopathies, and cerebral palsy.

Thrombi in the fetal circulation of the placenta cause a pattern of clustered fibrotic villi called fetal thrombotic vasculopathy (FTV), which has been associated with serious injuries to neonates, especially brain injuries. Correlation of FTV with visceral thrombi in autopsy specimens might lead to a more accurate estimate of the prevalence of somatic thrombi as a significant and underrecognized cause of prenatal injury or perinatal death, and show the potential validity of placental FTV as an indicator of thrombotic lesions in the fetus and newborns who survive. Clinicopathologic correlation was used to perform a 3-year retrospective autopsy review. We identified 16 cases (19%) among 84 perinatal autopsy specimens in which placental FTV was associated with stillbirth, intrapartum, or neonatal death. Two liveborn neonates survived 2.5 hours, and one for 24 hours; there was one intrapartum death, and the rest were stillborn. Clinical evidence of severe central nervous system (CNS) injury to two of the liveborn infants was evident at birth. Twelve stillborns died from 12 to 48 hours before delivery. Placental FTV had features of organization that clearly antedated the fetal death. Autopsy findings confirmed somatic thrombi in six cases (37.5%) of the 16 with FTV, including cerebral thrombi or infarcts (three cases), renal thromboemboli (three cases), and pulmonary thromboemboli (two cases). One mother had history of deep vein thrombosis, and four of eight tested had abnormal coagulation test results. Placental FTV indicates a significant probability of thrombi in the fetus and represents an important, possibly underrecognized cause of perinatal mortality and neonatal injury. Parental coagulopathy as a significant factor in prenatal injury and death deserves more comprehensive study. The placenta remains an undervalued and underutilized surgical specimen in the evaluation of perinatal injury, especially cerebral palsy.