位于宫腔的受精卵尚未发育到能着床的阶段而继续下移至子宫下方，并在该处生长发育而形成前置胎盘
11 位于宫腔的受精卵尚未发育 到能着床的阶段而继续下移 至子宫下方，并在该处生长 发育而形成前置胎盘
Classification分类
12 Classification 分类
完全性前部分性前边缘性前置胎盘置胎盘置胎盘MarginalTotalPartialplacentaplacentaplacentaprevia -- theprevia -- theprevia -- theplacenta is atplacentathe margin ofplacenta iscompletelytheinternal ospartially overcovers thethe cervixcervix.Normal PlacentaPartial Placenta PreviaTotal Placenta Previa
13 完全性前 置胎盘 部分性前 置胎盘 边缘性前 置胎盘 Total placenta previa - the placenta completely covers the cervix. Partial placenta previa - the placenta is partially over the cervix. Marginal placenta previa - the placenta is at the margin of the internal os
Total PlacentaPreviaFetusEndometriumPlacentaUmbilicalCordCervix
14
placentacervixItenine wallUmhilical cordCeniPlaccnta
15