SPIRAL ARTERIES An important aspect of placental development is the remodeling of the maternal uterine spiral arteries.
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Remodeling changes the spiral arteries into vein-like structures (high capacity, low resistance vessels) that can accommodate increased blood flow into the placenta. This is important for meeting the needs of the growing fetus.
Failed spiral artery remodeling can occur in preeclampsia, a life-threatening hypertensive disorder of pregnancy.
Remodeled Unremodeled spiral arteries https://pbs.twimg.com/media/CAlBqy1WQAABaZS.jpg
Unremodeled spiral arteries lead reduced blood flow into the placenta. http://www.bonyannews.ir/DesktopModules/DnnForge%20-%20NewsArticles/ImageHandler.ashx?Width=180&Height=120&HomeDirectory=% 2FPortals%2F0%2F&FileName=News%2F1394%2FPREECLAMPSI.jpg&PortalID=0&q=1&s=1
The placenta will release a variety of proteins in an effort to increase blood flow. These proteins can enter the maternal circulation and cause organ dysfunction, leading to the signs and symptoms of preeclampsia.