INDICATORS OF PLACENTAL MORPHOMETRY OF THE REPUBLIC SAKHA (YAKUTIA) INDIGENOUS WOMEN AT PHYSIOLOGICAL PREGNANCY

Abstract

The Republic of Sakha (Yakutia) is located in harsh climatic conditions, which is reflected in structural compensatory-adaptive changes in the placenta among residents of the region, but they remain poorly studied. The goal was to study the morphology of placentas of residents of the Republic of Sakha (Yakutia) under conditions of physiological pregnancy. All placentas corresponded to 36–41 weeks of gestation and delivered healthy children. The first observation group consisted of placentas of women of the indigenous population - Yakuts, Evenks, Evens and other small peoples of the North, born and permanently residing in the Republic of Sakha (79 cases); Group II – placentas from non-indigenous women (Russians, Ukrainians, Tatars and others) living in the Republic of Sakha for more than 10 years (70 observations) of the first and second mature periods. In this work, research was carried out at the organ and tissue levels of structural organization using a complex of morphological, clinical and instrumental methods. It was found that indigenous women were more likely to have paracentral umbilical cord attachment (65.8%), and in the group of non-indigenous women, central umbilical cord attachment was 3.3 times more likely to be observed (30%). Linear parameters of the placenta are characterized by the absence of statistically significant differences between the study groups. Histological studies showed that in non-indigenous women of the republic, compared with the group of indigenous women, the area of terminal villi was significantly greater than that in non-indigenous women by 1.8 times (p=0.016). With identical indicators of the number of vessels in the terminal villi, a low vascular-stromal coefficient of terminal villi was determined (p=0.019) due to an increase in the stromal component (p=0.03), which indicates the presence of relative hypovascularization. An increase in the area of terminal villi was revealed by 1.8 times in the placentas of the group of indigenous women (p=0.016), which is significantly greater than the same indicator in the group of non-indigenous women. The identified data can be considered as evidence of adaptive restructuring in the fetal part of the blood-placental barrier of the placenta to specific ecological and territorial living conditions.