Although circulating microRNAs (miRNAs) in maternal blood may play an important role in regulation of pregnancy progression and serve as non-invasive biomarkers for different gestation complications, little is known about their profile in blood during normally developing pregnancy. In this study we evaluated the miRNA profiles in paired plasma and serum samples from pregnant women without health or gestational abnormalities at three time points using high-throughput sequencing technology. Sequencing revealed that the percentage of miRNA reads in plasma and serum decreased by a third compared to first and second trimesters. We found two miRNAs in plasma (hsa-miR-7853-5p and hsa-miR-200c-3p) and 10 miRNAs in serum (hsa-miR-203a-5p, hsa-miR-495-3p, hsa-miR-4435, hsa-miR-340-5p, hsa-miR-4417, hsa-miR-1266-5p, hsa-miR-4494, hsa-miR-134-3p, hsa-miR-5008-5p, and hsa-miR-6756-5p), that exhibit level changes during pregnancy (p-value adjusted < 0.05). In addition, we observed differences for 36 miRNAs between plasma and serum (p-value adjusted < 0.05), which should be taken into consideration when comparing the results between studies performed using different biosample types. The results were verified by analysis of three miRNAs using qRT-PCR (p < 0.05). The present study confirms that the circulating miRNA profile in blood changes during gestation. Our results set the basis for further investigation of molecular mechanisms, involved in regulation of pregnancy, and the search for biomarkers of gestation abnormalities.

For today, twins make up about 1.5% of the population of our planet. It is more than one hundred million people, which in number corresponds to the population of two Frances. The number of twins born relative to the total number of newborns in different countries and on different continents is different, but the overall trend is that it continues to grow. In recent years, the percentage of multiple pregnancy has increased almost 2.5 times, which is associated with the widespread use of assisted reproductive technologies.At the same time, pregnancy in multiple births is an extremely important problem in modern obstetrics, as it is accompanied by a high level of complications for both the mother and the fetuses. Multiple pregnancy contributes significantly to the formation of adverse perinatal outcomes, which is primarily due to the high rate of preterm birth. Premature twins are at high risk of neurological and neuropsychiatric disorders, respiratory distress, endocrine and metabolic disorders, which subsequently become the cause of disability and social maladaptation of children. In this regard, the reduction in the number of premature births is today a priority task, the solution of which is possible only through timely and correct forecasting. The multifactority of pathogenic mechanisms determines the necessity of diagnostic search strategies that can identify markers of various pathogenetic ways of preterm birth. (For citation: Kosyakova OV, Bespalova ОN. Challenges and prospects of preterm birth prediction in multiple pregnancies. Journal of Obstetrics and Women’s Diseases. 2018;67(4):48-59. doi: 10.17816/JOWD67448-59).

Complications endangering mother or fetus affect around one in seven pregnant women. Investigation of the genetic susceptibility to such diseases is of high importance for better understanding of the disease biology as well as for prediction of individual risk. In this study, we collected and analyzed GWAS summary statistics from the FinnGen cohort and UK Biobank for 24 pregnancy complications. In FinnGen, we identified 11 loci associated with pregnancy hypertension, excessive vomiting, and gestational diabetes. When UK Biobank and FinnGen data were combined, we discovered six loci reaching genome-wide significance in the meta-analysis. These include rs35954793 in FGF5 (p=6.1×10−9), rs10882398 in PLCE1 (p=8.9×10−9), and rs167479 in RGL3 (p=5.2×10−9) for pregnancy hypertension, rs10830963 in MTNR1B (p=4.5×10−41) and rs36090025 in TCF7L2 (p=3.4×10−15) for gestational diabetes, and rs2963457 in the EBF1 locus (p=6.5×10−9) for preterm birth. In addition to the identified genome-wide associations, we also replicated 14 out of 40 previously reported GWAS markers for pregnancy complications, including four more preeclampsia-related variants. Finally, annotation of the GWAS results identified a causal relationship between gene expression in the cervix and gestational hypertension, as well as both known and previously uncharacterized genetic correlations between pregnancy complications and other traits. These results suggest new prospects for research into the etiology and pathogenesis of pregnancy complications, as well as early risk prediction for these disorders.

Premature birth is one of the most important problems of modern obstetrics because it is a leading cause of childhood morbidity and mortality in all countries. Annually, > 1 million premature newborns worldwide die from various types of complications, and most of the survivors become disabled. Moreover, according to WHO analysis, most of these children can be saved by developing measures for the early identification of preterm births, which will provide additional time for effective intervention. Currently, available diagnostic methods do not adequately assess the risks of premature delivery owing to the low predictive value of the methods. This makes it necessary to search for predictors of preterm labor that can improve the accuracy of diagnostic techniques. The desired predictors should have a pathogenetic basis, and most importantly, they must contribute to the early detection of life-threatening premature births. The hormone relaxin could be considered to be a promising marker of premature birth because its role in the pathogenesis of premature birth is unquestionable, and the evaluation of its levels is possible during the early stages of pregnancy.

Aim. To study changes in the level of piRNA in plasma and serum of pregnant women at different stages of gestation.Material and Methods. A total of 42 samples of plasma and blood serum were obtained from seven women with physiological singleton pregnancy without obstetric and gynecological pathology. The study was carried out at three time points corresponding to 8–13, 18–25, and 30–35 weeks of pregnancy, respectively. To assess the spectrum and levels of piRNA by the NGS method, whole genome sequencing of small RNAs was carried out. Sequencing data analysis was performed using the GeneGlobe Data Analysis Center web application. Differential expression was assessed using the DESeq2 R package.Results and Discussion. The piRNA contents among all small RNAs were 2.29%, 2.61%, and 4.16% in plasma and 7.29%, 7.02%, and 10.82% in serum during the first, second, and third trimesters, respectively. The contents of the following piRNAs increased in blood plasma from the first to the third trimester: piR 000765, piR 020326, piR 019825, piR 020497, piR 015026, piR 001312, and piR 017716. The study showed that the levels of piR 000765, piR 020326, piR 019825, piR 015026, piR 020497, piR 001312, piR 017716, and piR 004153 were significantly higher in serum compared with the corresponding values in plasma whereas the content of only one molecule, piR 018849, was higher in plasma.Conclusion. This pilot work created a basis for understanding the processes of piRNA expression in plasma and serum of pregnant women and can become the foundation for the search for biomarkers of various complications in pregnancy.

Preterm birth in multiple pregnancy is an important medical, economic and social problem. Currently, more than half of twins are born prematurely, which puts them at high risk of developing neonatal diseases causing lifelong disability and social maladjustment. In this regard, reducing the frequency of preterm multiple births is an important task of modern obstetrics. Improving perinatal outcomes of multiple pregnancies can only be achieved using the most effective measures that have a good evidence base. At the same time, numerous studies on the effectiveness of therapeutic interventions aimed at prolonging multiple pregnancies have reported contradictory results. This review included most of the randomized controlled trials of methods for the prevention and treatment of threatening preterm birth in multiple pregnancies, as available in PubMed, Google Academy, Elibrary, and the Cochrane Central Register of Controlled Trials. Thus far, studies on the use of bed rest, prophylactic tocolysis, most of the progestins, and cervical cerclage in multiple pregnancy have shown no efficacy in reducing the risk of premature birth. However, encouraging data were obtained on improving neonatal outcomes of multiple pregnancies using vaginal progesterone and an obstetric pessary, but these results require additional confirmation in larger multicenter randomized studies. Further clinical trials are needed to develop algorithms for timely diagnosis and adequate treatment of threatened preterm birth in case of multiple pregnancy, including the use of the most rational preventive and therapeutic methods that have a high evidence level.

BACKGROUND: Preeclampsia is a multisystem complication of pregnancy associated with an increased risk of maternal / perinatal morbidity and mortality. In this regard, the development and following improvement of low-cost and convenient methods for diagnosis of preeclampsia is essential for accurate prediction, quick confirmation of the diagnosis and convenient monitoring of the pathology. AIM: The aim of this study was to optimize a preeclampsia diagnosis test system based on the binding of proteins to the Congo red dye (CRD test). MATERIALS AND METHODS: The study used 70 urine samples obtained from patients diagnosed with preeclampsia (n = 25) and from non-preeclampsia pregnant women (n = 45). The samples were stained with Congo red and the dye retention in the sample on the membrane after washing was calculated. Before staining, protein concentrations in the urine samples were equalized using centrifugal concentrators or the samples were used with the original protein concentrations. To wash the samples from the unbound dye, either methanol or ethanol was used. To compare the effectiveness of four CRD test variants differing in sample preparation, staining, and washing, ROC analysis was performed (IBM SPSS Statistics 20 software). RESULTS: The express CRD test was designed as an optimization of the conventional CRD test. The effectiveness of the express test (the area under the ROC curve being 0.9) was higher than that of the other three test options (the area under the ROC curve ranges from 0.67 to 0.82). The developed express CRD test can provide 95% specificity and 73% sensitivity, which indicates the promise of using this method in clinical diagnostics for the specific detection of preeclampsia patients. CONCLUSIONS: Optimization of the CRD test has provided more effective protocols for diagnosis of preeclampsia from urine samples using Congo red (express CRD test) and has simplified the routine application of this test in clinical practice.

In recent years evidence has been accumulated showing that miRNAs can act as potential biomarkers or targets for therapy of preterm birth, one of the most important problems in modern obstetrics. We have performed a prospective study of the miRNA profile in the plasma during the first and second trimesters in pregnant women with high risk of preterm birth (n = 13 cases and n = 11 controls). For the study group plasma blood samples at 9–13 weeks before diagnosis and at 22–24 weeks after start of therapy were selected. Using high-throughput sequencing technology we detected differences in the levels of 15 miRNAs (3 upregulated—hsa-miR-122-5p, hsa-miR-34a-5p, hsa-miR-34c-5p; 12 downregulated—hsa-miR-487b-3p, hsa-miR-493-3p, hsa-miR-432-5p, hsa-miR-323b-3p, hsa-miR-369-3p, hsa-miR-134-5p, hsa-miR-431-5p, hsa-miR-485-5p, hsa-miR-382-5p, hsa-miR-369-5p, hsa-miR-485-3p, hsa-miR-127-3p) (log2(FC) ≥ 1.5; FDR ≤ 0.05) during the first trimester compared with the control (non-high-risk of preterm birth pregnant women). All downregulated miRNAs in the first trimester from the placenta-specific C14MC cluster. During the second trimester no differentially expressed miRNAs were found. Our results suggest that the miRNA profile in plasma during early pregnancy may predict a high risk of preterm birth, which is important in preventing gestational problems as early as possible.