[The birthing chair, obstetric bed and gynecological chair in obstetrics and gynecology in Russia of XVIII-XX centuries].

The purpose of the study is to investigate material culture of obstetrics in New and Modern history of Russia. The most important objective of research is to involve into scientific circulation Russian empirical material in order to study transformation of culture of childbirth during transition from traditional to biomedical model of childbirth exemplified by material culture items (maternity beds, chairs, armchairs). The key approaches were those of historical anthropology, social history of medicine, theory of social control and medicalization. The methods of content analysis, narrative and interpretive analysis were applied to analyze empirical data. In the Russian folk tradition included no such special devices as maternity beds and birth chairs that was explained by dominance of vertical maternity pose. The first birth chairs were brought into Russia by foreign midwives. With development of clinical obstetrics horizontal position of woman in labor was approving that was conditioned by convenience of physicians. Since last quarter of the XIX century, Russian physicians began to experiment, inventing most convenient version of maternity beds and gynecological chairs. The Soviet system of obstetrics was mass and publicly accessible, but consolidated technocratic model of childbirth. In maternity wards, the "Rakhmanov obstetric bed" became widespread. The chairs were not used during childbirth, being used exclusively in gynecology. The material culture of Soviet maternity hospitals turned out to be extremely stable and conservative. In modern Russian obstetrics, with transition to holistic model of childbirth and actualization of free positioning of woman in labor, transformer beds and fitballs began to be applied to provide optimal course of birth process. The material culture of obstetrics is closely related to dominant type of maternity culture.

[Vitamin D and pregnancy: current state of the problem in the central regions of the Russian Federation].

BACKGROUND: It has been proven that vitamin D plays an important role in pregnancy. Deficiency of this element may be associated with the risk of developing gestational diabetes mellitus, preeclampsia, placentar insufficiency, low birth weight and premature birth. AIMS: To conduct an epidemiological analysis of vitamin D supply in women at different stages of pregnancy, living in Russia. MATERIALS AND METHODS: We included 1198 pregnant women living in 3 regions of Russia in the observational, multicenter, cross-sectional, continuous study. All pregnant women were tested for serum 25(OH)D levels. We collected biomaterial from August 2018 to December 2019. The end point of the study was the indicator of vitamin D supply in pregnant women and its level depending on the trimester of pregnancy and region of Russia. Statistical analysis included counting and grouping according to vitamin D levels, and calculating the median vitamin D concentration in each region. RESULTS: We confirmed vitamin D deficiency in all regions. The optimum level of this element is present in less than 7% of women. Insufficiency of this element is present in 20,62% of all women. The largest percentage of them is in a deficit of this element - 46,66%. We found that the lowest rates are in Smolensk, where the median was 12,75 ng/ml. In addition, we found changes in vitamin D concentration: with an increase in gestational age revealed a decrease in its level. CONCLUSIONS: In our study, we confirmed the presence of a 25(OH)D deficiency in most of the examined pregnant women, which is consistent with international epidemiological data. We should remember about these both at the stage of pre-gravid preparation and at the stage of pregnancy itself in order to achieve the optimal level of vitamin D.