ABSTRACT
This study was done to investigate the histological changes of the human placentae in postmaturity and preeclamptic conditions after an ultrasound scanning follow up of the pregnant females. Ten human normal, postmature and preeclamptic placentae were obtained from the Maternity Hospital, Faculty of Medicine, Ain-Shams University. The ultrasonic scanning revealed complete compartmentization, septation and calcification of the postmature placenta and infarction of the preeclamptic placentae with intrauterine growth retardation of the fetuses. Histologically, postmature and preeclamptic placentae showed thin degenerated syncytium with deeply stained nuclei in areas and increasing numbers of syncytial knots and cytotrophoblastic proliferation in other areas compared to the normal full term placenta. The villous core of the normal placenta was loosely textured whereas that of the postmature and preeclamptic placentae was dense and fibrotic. Infarcts was evident in preeclamptic with increased fibrin deposition seen in postmature placenta as well. Although diminished vascularity of the postmature villi was described, the preeclamptic villi showed dilatation and congestion of the villous capillaries: thickening arteriolar wall was a common finding. Glycogen deposition [as evident by PAS stain] increased in toxemic and postmature placentae. These findings were due to placental insufficiency and ischemia associated with fetal growth retardation and increased fetal mortality