Vol 71, No 4 (2022)

This review presents data on the circadian system hierarchy and its unique reorganization at the onset of pregnancy, which plays a fundamental role in maintaining maternal homeostasis and creating optimal conditions for the implementation of the genetic program of fetal development. A particular emphasis is made on the protective mechanisms of the circadian rhythm of maternal melatonin, which is the primary messenger of biorhythms. This paper thoroughly discusses the mechanisms and consequences of maternal chronodisruption in pregnant women exposed to adverse environmental conditions (shift work, stress, irregular nutrition, etc.), as well as in those with chronodestruction-related diseases (obesity, diabetes mellitus, etc.). Elucidating the circadian system status in the patients and, in particular, whether they have a daily rhythm of melatonin production will determine a new approach to risk assessment and timely prevention of cardiovascular, metabolic, neuroendocrine and mental disorders in the offspring in later life.

BACKGROUND: At present, the knowledge on initial human embryogenesis stages is limited to the period of development from zygote to blastocyst. The creation of models based on the interaction between the embryo and endometrium in vitro, which accurately imitate the in vivo processes, represents the major way for implantation and post-implantation evaluation. Currently, no reports have been made on models reflecting the both processes simultaneously: the interaction of the embryo with the substrate, which represents many aspects of normal implantation, and the early post-implantation embryo development. The creation of a relevant model would allow investigation of implantation and early post-implantation processes as a whole.

AIM: The aim of this study was to evaluate the vitality and developmental potential of human embryos from the day 6 blastocyst stage during their extended co-incubation with the endometrium in a culture medium specifically designed for cultivation to the blastocyst stage.

MATERIALS AND METHODS: Embryos obtained in assisted reproductive technology programs were cultivated from the day 6 blastocyst stage up to 14 days of development in vitro in a culture medium designed for cultivation to the blastocyst stage, in the presence of endometrium cells. On day 14 of development, embryos and endometrial samples were first evaluated under an inverted microscope using Hoffman modulation contrast, then transferred to a special mold and impregnated with paraffin for cytoblock preparation. Obtained blocks were sliced, stained with hematoxylin and eosin and morphologically assessed.

RESULTS: The first sample visual assessment on day 14 of cultivation in a culture medium with endometrium cells revealed a viable developing embryo with no signs of degradation. During the histological examination, the endometrial sample corresponded to the secretory phase of the cycle. The morphological assessment of the conceptus detected trophoblast cells. The second sample visual assessment on the day 14 of cultivation in a culture medium with endometrium cells revealed a viable embryo with no signs of degradation, which was in direct contact with the endometrial component. A histological examination detected a secretory endometrial fragment of the surface (luminal) epithelium. During the morphological assessment of the embryo, trophoblast cells were detected.

CONCLUSIONS: The data obtained indicate the ability of the embryo to further develop from the day 6 blastocyst stage up to 14 days in a culture medium specifically designed for cultivation to the blastocyst stage, in the presence of endometrium cells. The latter can serve as an experimental model for both in vitro endometrial receptivity evaluation and intercellular interactions during implantation investigation.

BACKGROUND: The rapid increase in the frequency of caesarean sections has led to the emergence of a special group of patients with a uterine scar who want to give birth through the natural birth canal. Repeated operative delivery is associated with high risks of both intraoperative and postoperative complications, therefore, every year the number of women with a uterine scar who prefer natural childbirth is growing.

AIM: The aim of this study was to create a model that allows, based on a comprehensive assessment of risk factors, for predicting the outcome of childbirth in women with a history of abdominal childbirth.

MATERIALS AND METHODS: We carried out a retrospective analysis of 173 birth histories of women with a uterine scar after a previous caesarean section, delivered in the Chita City Maternity Hospital in 2021–2022. Three groups of individuals were designed for the study: Group 1 included 110 women delivered by caesarean section in a planned manner; Group 2 comprised 20 women delivered by caesarean section during childbirth, while Group 3 consisted of 43 women who gave birth through the natural birth canal. The groups were comparable in terms of nationality, age, material and social conditions of the patients. On the eve of delivery, all patients underwent general clinical and obstetric ultrasound examination, with the anamnesis details clarified. The data obtained were processed statistically using the IBM SPSS Statistics version 25.0.

RESULTS: Using binary logistic regression, a model was developed to predict the outcome of childbirth through the natural birth canal in women with a uterine scar, which takes into account statistically significant indicators such as gestational age, estimated fetal weight, parity, and the presence of chronic endometritis and weakness of labor activity in history. The sensitivity of the developed prognostic model is 0.86, the specificity being 0.70. The area under the ROC curve is 0.87 (95% confidence interval 0.78–0.96; p < 0.001).

CONCLUSIONS: The comprehensive analysis of risk factors allows for predicting the outcome of natural childbirth in women with a uterine scar, which in the future will optimize the tactics of their delivery and prevent the development of complications in childbirth for the mother and fetus.

BACKGROUND: The prevalence of endometriosis among women of reproductive age and the complexity of choosing the methods for its effective treatment necessitate the study of the clinical and morphological features of ovarian endometriosis in its recurrent course, as well as the search for available informative diagnostic and prognostic markers which allow identifying risk groups for relapse and form prevention methods. Endometriomas have a recurrence rate of 50–55 % after treatment.

AIM: The aim of this study was to conduct a comparative analysis of cell immune regulation features in recurrent ovarian endometriosis.

MATERIALS AND METHODS: We studied clinical data, the value of peripheral immunocompetent blood cells, as well as morphological and immunohistochemical data of 196 patients operated on for endometrioid ovarian cysts, including 45 patients with a recurrent course of the disease and 151 women without relapse. Monoclonal mouse antibodies to T helpers (CD4), T killers (CD8), B lymphocytes (CD20), and macrophages (CD68) were used for immunohistochemical examination of the surgical material. Immunological examination of peripheral blood was performed by flow cytometry with the assessment of helper T lymphocyte, killer T lymphocyte and B lymphocyte subpopulations and their ratios.

RESULTS: The recurrence rate of endometrioid ovarian cysts was 22.96%. Most patients (48.87%) relapsed 3–4 years after the first operation. In patients with recurrent endometrioma, we more often detected complaints of dyspareunia, dysmenorrhea, primary infertility and a history of operations on the uterine appendages unrelated to endometriosis in anamnesis, as well as the third degree of the pathological process. During morphological examination, the glandular-cystic variant and morphologically active lesions were detected more often in recurrent endometriosis compared to the relapse-free course. Cytotoxic T killers (CD8) and macrophages (CD68) were shown to be the predominant subpopulation of cells found in the inflammatory infiltrate of cytogenic stroma and endometrioid cyst capsule. More of them were detected in recurrent endometrioid cysts in the surgical material of both the first and second operations compared to the relapse-free course. B lymphocyte count was significantly higher in the cyst capsule with recurrent endometriosis than in cases of the relapse-free course. T helpers (CD4) were found only in the surgical material of an already diagnosed recurrence. Immunological examination of peripheral blood of patients with recurrent endometrioma revealed an increase in the total population of T lymphocytes due to a subpopulation of T helpers, the number of which per microliter exceeded the reference values.

CONCLUSIONS: An increase in the number of free stromal cells in the foci of endometriosis with its recurrent course indicates the importance of hyperreactivity and the autoimmune mechanism in the chronization and progression of the disease.

BACKGROUND: Oligohydramnios in preterm premature rupture of membranes is the cause of increased perinatal morbidity and mortality among preterm newborns. Microbiological features in women with preterm premature rupture of membranes and oligohydramnios are probably some of the determining factors affecting the implementation of an unfavorable outcome of gestation.

AIM: The aim of this study was to determine microbiological features and perinatal outcomes in patients with preterm premature rupture of membranes and oligohydramnios.

MATERIALS AND METHODS: This retrospective study conducted from 2018 to 2021 included 161 pregnant women with PPROM at 24 to 33 weeks and 6 days of gestation. Of these, the main group consisted of 83 patients with signs of oligohydramnios, while the control group comprised 78 patients without oligohydramnios. Patient examination upon admission to the hospital included analysis of the amniotic fluid index, the white blood cell differential, plasma ferritin and C-reactive protein levels, and bacteriological tests of vaginal secretions by isolating and growing microbes on optimal culture media.

RESULTS: The patients with oligohydramnios had shorter latent period (р = 0.004), but the noted distinctions were a higher frequency of clinical chorioamnionitis (р = 0.025), fetal distress (р = 0.030), and earlier parturition (р = 0.040) with more frequent caesarean sections (р = 0.016) compared to the control group. Vaginal microbiota in the main group showed a higher prevalence of Staphylococcus aureus (р = 0.008), Bacteroides spp. (р = 0.030), Streptococcus spp. (р = 0.002), Micrococcus spp. (p < 0.001), Bacillus subtilis (p < 0.001), Bacillus megaterium (p = 0.009), Bacillus buchneri (р = 0.008), Klebsiella pneumoniae (р = 0.002), Haemophilus spp. (р = 0.005) and no Candida albicans compared to the control group. In the main group, newborns more often had a lower body weight at birth (р = 0.002) and a lower Apgar score at the fifth minute (р = 0.011). They also showed higher incidences of respiratory distress syndrome (р = 0.006), bronchopulmonary dysplasia (р = 0.036), congenital pneumonia (р = 0.011) and necrotizing enterocolitis (р = 0.022) and more often needed treatment in an intensive care unit (р = 0.034), including surfactant supplementation (р = 0.007), cardiotonic support (р = 0.004) and artificial lung ventilation (р = 0.006) compared to the control group.

CONCLUSIONS: Oligohydramnios in preterm premature rupture of membranes is associated with pronounced dysbiotic changes in the vaginal microbiota including the prevalence of Micrococcus spp., Streptococcus spp., Staphylococcus aureus and absence of Candida spp. from the isolates, as well as increased incidence of adverse perinatal outcomes.