Objective: To investigate the pathological characteristics of singleton placenta with abnormal shape and its influence on the outcome of maternal-fetal pregnancy. Methods: The clinicopathological data of singleton placentas with abnormal shape from January 2014 to December 2020 in the Department of Pathology, Haidian Maternal and Children Health Hospital were analyzed retrospectively. Results: There were 130 singleton placentas with abnormal shape in this cohort, including 48 succenturiate placentas, 12 bilobed placentas, 50 marginate placentas, 13 circumvallate placentas, 3 annular placentas, 2 membranous placentas and 2 fenestrated placentas. Gestational age ranged from 29+5 to 40+4 weeks. There were 51 cases of premature rupture of membranes, 11 cases of placenta previa, 5 cases of placental abruption, 15 cases of placental adhesion/implantation and 27 cases of postpartum hemorrhage. There were 46 preterm fetuses,28 fetuses with fetal growth restriction, 22 fetuses with intrauterine distress, and 1 fetus with intrauterine death. Grossly, the placental lobules of succenturiate placentas had apparent size difference, while two lobules of bilobate placenta were more consistent. The chorionic plate size was smaller than the bottom plate of circumvallate placenta, the folded fetal membrane in the rim of placenta was thickened (termed marginate placenta if there was no thickening). The membranous placenta was characterized by a thin, large membrane-like shape. Annular placenta showed characteristic hollow cylinder, ring or horseshoe-shape. Fenestrated placenta was characterized by tissue defects near central area. Microscopically, functional/morphologic changes were the main manifestations of inadequate maternal-fetal perfusion, including villous infarction, distal villous dysplasia and excessive villous maturation. Conclusions: The abnormal shaped singleton placentas showed variable extent of inadequate maternal-fetal perfusion, which may lead to adverse pregnancy outcomes such as premature delivery, fetal growth restriction, intrauterine distress or fetal death.
目的： 探讨形状异常的单胎胎盘病理学特点及对母胎妊娠结局的影响。 方法： 回顾性分析北京市海淀区妇幼保健院病理科2014年1月至2020年12月临床送检的形状异常的单胎胎盘130例临床病理资料。 结果： （1）130例形状异常的单胎胎盘，包括副叶胎盘48例、双叶胎盘12例、有缘胎盘50例、轮廓胎盘13例、环状胎盘3例、膜状胎盘2例及有窗胎盘2例。（2）产妇孕周29+5~40+4周，51例胎膜早破，11例胎盘前置，5例胎盘早剥，15例胎盘粘连/植入，27例产后出血。（3）胎儿中有46例未足月早产，28例生长发育受限，22例宫内窘迫，1例胎儿宫内死亡。（4）胎盘大体特点：副叶胎盘表现为分叶有明显的大小差异，若两叶大小较一致，称为双叶胎盘；轮廓胎盘表现为绒毛膜板小于底板，边缘反折的胎膜有明显增厚，若未见增厚，则称为有缘胎盘；膜状胎盘大体特点为薄而大，形似薄膜；环状胎盘大体表现为空心圆柱体状、环形或马蹄形；有窗胎盘表现为近中央区有组织缺损。（5）镜下改变：以功能性形态学改变为主，常见母胎灌注不足的表现，包括绒毛梗死、远端绒毛发育不良及绒毛过度成熟等。 结论： 形状异常的单胎胎盘大体表现各异，母胎灌注功能不足，可导致胎儿早产、胎儿生长受限、宫内窘迫或胎死宫内等不良妊娠结局。.