Placental morphology – from theory to practice

Abstract

The article provides a review of the literature on modern studies of macroscopic and microscopic changes in the placenta of the cases of complicated childbirth and diseases of the newborn. From a clinical point of view, the values ​​of such indicators as the length, tortuosity of the umbilical cord, its entry into the placenta are indicated. In particular, the influence of the length of the umbilical cord on the course of childbirth was considered – from an increased frequency of birth of children with a low Apgar score with a short umbilical cord to an increase in the risk of entanglement, prolapse, and a true knot of a long umbilical cord. The article explains the reasons for the formation of the tortuosity of the umbilical cord, data on its types and impact on the course of labor. The weight of the placenta is considered both in terms of absolute performance and from new perspectives on the assessment of placental-fetal ratio. In particular, its dynamics with the progression of the gestational period are presented, as well as the effect of its decrease on the increase in the risk of further development of diabetes mellitus and gestational hypertension in the mother. The researches that provide clinical rope of the macroscopic findings such as placental infarctions and retroplacental hematomas are analyzed. Acute and subacute infarction, as well as differences between retroplacental hematoma and clinically expressed premature placental abruption, are described. The processes and histological changes that accompany the maturation of chorionic villi, as well as the typical manifestations of insufficient remodeling of the spiral arteries, which, according to modern concepts, are the basis for the development of most gestational complications, are considered. A new concept for Ukrainian resources, such as the “villi maturity index”, which is defined as the ratio of the number of vascular syncytial membranes in 1 cm2 of the studied area of ​​the sample to the thickness of these membranes, is presented. It is known that a significant decrease of this indicator due to a decrease in the number of membranes and an increase in their thickness is typical in pregnancies complicated by severe preeclampsia and gestational diabetes mellitus.