Benirschke K
Department of Pathology, University of California, San Diego Medical Center 92103-8321.
Semin Diagn Pathol. 1993 Aug;10(3):222-31.
In multiple gestations, intrauterine death of one fetus occurs frequently. Sonographic studies indicate that many twin pregnancies are converted in early pregnancy to singletons. The "vanished" twin is sometimes recognized as a fetus papyraceous (compressus) incorporated into the placenta of the survivor. Death of one twin later in pregnancy may have serious implications for the survivor, especially in cases of monochorionic twins. One postulated mechanism has been that thromboplastic proteins from the dead twin are transfused into the survivor's circulation, resulting in disseminated intravascular coagulation. More recently it has been proposed that massive blood loss may occur from the survivor into the more relaxed circulation of a dead monochorionic twin through vascular anastomoses. These mechanisms may explain the higher frequency of cerebral palsy in monochorionic twins. These concepts emphasize the importance of careful examination and thoughtful interpretation of twin placentas.
在多胎妊娠中，一个胎儿的宫内死亡很常见。超声研究表明，许多双胎妊娠在孕早期会转变为单胎妊娠。“消失”的双胎有时会被识别为纸样（压扁）胎儿，融入存活胎儿的胎盘。妊娠后期一个双胎死亡可能对存活胎儿有严重影响，尤其是在单绒毛膜双胎的情况下。一种推测的机制是，来自死亡双胎的促凝血蛋白输入到存活胎儿的循环中，导致弥散性血管内凝血。最近有人提出，存活胎儿可能通过血管吻合处大量失血到死亡的单绒毛膜双胎更松弛的循环中。这些机制可能解释了单绒毛膜双胎中脑瘫发生率较高的原因。这些概念强调了仔细检查和认真解读双胎胎盘的重要性。
