The aim of this research is to study the potential role of miR-21 and miR-210 as markers of anxiety during pregnancy. <...> There was studied the expression of the level of microRNA 21 and 210 in the whole blood of pregnant women with diff erent level of anxiety. <...> According to the results, the level of anxiety in pregnancy correlates with the level of microRNA 21 and 210. <...> These micro RNAs are hypoxic, and they regulate the expression of genes that are involved in the development of essential obstetric pathology - preeclampsia and IUGR (intra-uterine growth retardation) of a fetus. <...> So, women with high level of anxiety are at high risk of obstetric and perinatal complications. <...> They include: 1) an increase in the rate of complications during pregnancy and birth; 2) an increase in the number «Репродуктивное здоровье. <...> Восточная Европа» 2016, том 6, № 5 615 MicroRNA-21. -210 – современные маркеры стресса у беременных of miscarriages and premature births; 3) the birth of a fetus with low birth weight as a result of both premature births and developmental delays of a fetus in full term pregnancies; 4) the birth of children with various degrees of asphyxia (low Apgar scale scores); 5) neurological and psychological disorders; 6) propensity for allergic reactions. <...> Thus, the study of the eff ect of stress during pregnancy is a factor as important to medical science as the study of obstetric, somatic, infectious and other disorders. <...> The mechanisms of the eff ects of stress and anxiety as it result on the mother and baby have to be studied especially carefully to determine the potential markers of stress. <...> So we became interested in published studies on the potential role of microRNA (miR) in stress adaption reactions and their potential role in the development of obstetric disorders. <...> MicroRNA – is a class of small non-coding RNA molecules, about 22 nucleotides in length, which were discovered in 1996. <...> MicroRNA plays a part in most processes of life, from fertilization to growth and development, in the onset of various disorders and in the adaptation reactions including adapting to stress [4]. <...> Some of them circulate freely in the blood, others are located in tissues. <...> Most studies that have been conducted during the time of pregnancy where on specifi c circulating placenta miRNA, that can be found in the mother’s blood and can be a marker <...>