Increased Syncytial Knot Formation

  • W. Tony ParksEmail author


Syncytial knots are a common histologic feature of the placenta. This overarching term includes four specific subtypes of syncytial knots, including syncytial sprouts, true knots, false knots and syncytial bridges. Wave-like syncytial knots represent a specific architectural arrangement of syncytial knots generally found at earlier gestational ages. Increased syncytial knots have long been associated with adverse pregnancy outcomes, including preeclampsia and fetal growth restriction, and are a defining feature of maternal vascular malperfusion. More specifically, increased syncytial knots appear to arise in response to hypoxic or hypoxia-reperfusion injury to the placenta.


Syncytiotrophoblast Preeclampsia Hypoxia Fetal growth restriction Malperfusion 


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of PathologyNorthwestern University Feinberg School of MedicineChicagoUSA

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