Peculiarities of placental structures in women with preterm labor
Authors:   Bogomolets National Medical University, Kyiv, Tkalich V.O. , Poladich I.V. ,   Bogomolets National Medical University, Kyiv, Kupchik V.I. ,   Bogomolets National Medical University, Kyiv
Published: September 2021

The objective: study of histochemical, morpho-functional features of placentas in premterm birth at different gestational ages. Materials and methods. We examined 172 pregnant women, who were hospitalized and gave birth in the Perinatal Center of Kyiv during 2016–2018 years at 24–33 weeks of gestation. The control group included 40 women with a physiological course of singleton pregnancy at 38–41 weeks of gestation. Patients of the experimental group were divided into three subgroups: the first consisted of 46 pregnant women at 22–27 weeks of gestation, the second one – of 44 pregnant women at 28–33 weeks, the third one – of 42 pregnant women at 34–37 weeks. Clinical and statistical analysis of exchange cards of pregnant women (form 113/y) and birth histories (form 096/0) of mothers of all groups was performed. For morphofunctional assessment of placenta in the study histological (staining with hematoxylin-eosin after Van-Gizon) and immunohistochemical (indirect streptavidin-peroxidase – for detection of progesterone receptor’s expression level) methods were used. Results. No significant age difference was found between the study groups. More than 66.5% of patients had a second pregnancy. Obstetric and gynecological history of women are burdened in most cases by the following conditions: previous premature birth, miscarriage, inflammatory diseases, extragenital pathology (diseases of the urinary and endocrine systems). When analyzing the results of histological examination of the placenta in patients whose pregnancies resulted in childbirth at 22–27 weeks, inflammatory changes in the placenta were found in 84.8%, and in women in labor at 28–33 weeks – only 56.8%. At 34–37 weeks of gestation, the percentage of inflammatory changes in placental structures do not have a significant difference with the control group (30.9% and 27.5%, respectively; p≤0.05). With gestational age increase the percentage of involutive-dystrophic changes in the placenta decreases, the number of circulatory disorders increases, and accelerated chorionic maturation is observed. Analysis of the data of monoclonal antibodies’ to progesterone receptors expression in the structures of the placenta depending on gestational age revealed the greatest expression in decidual membranes (55%) in very early preterm birth, which had a significant difference with the control group (14%), (p<0.05) . In women of group II, the level of expression of progesterone receptors was reduced (30%), but had no significant difference with group III of the studied placentas (26%), (p>0.05). Immunohistochemical examination of the progesterone receptors (PR) shows a reaction in the epithelium and stem cells of the stroma, intermediate and terminal villi; in amniotic membranes and extravillous cytotrophoblast; in the vascular endothelium. Conclusion. In very early preterm birth, inflammatory changes and significant expression activity of progesterone receptors predominate in placental structures. During childbirth at 33–37 weeks of gestation the most common disorders are maturation of the villous chorion, combined with circulatory and involutive-dystrophic changes. Keywords: preterm labor, placenta, histological changes, immunohistochemistry, progesterone receptors.