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Journal of Assisted Reproduction and... Dec 2020Chronic endometritis (CE) is a frequent hysteroscopic and histological finding which affects embryo transfer implantation during IVF-ICSI cycles. In particular, CE...
PURPOSE
Chronic endometritis (CE) is a frequent hysteroscopic and histological finding which affects embryo transfer implantation during IVF-ICSI cycles. In particular, CE impairs proper decidualization and, subsequently, implantation. Although this correlation has been clearly clarified, a pathophysiological explanation assembling all the studies performed has not been elucidated yet. For this reason, we have structured a systematic review considering all the original articles that evaluated a pathological element involved in CE and implantation impairment.
METHODS
The authors searched electronic databases and, after screening, collected 15 original articles. These were fully scanned and used to create a summary pathway.
RESULTS
CE is primarily caused by infections, which lead to a specific cytokine and leukocyte pattern in order to prepare the uterus to fight the noxa. In particular, the immunosuppression requested for a proper semi-allogenic embryo transfer implantation is converted into an immunoreaction, which hampers correct embryo implantation. Moreover, endometrial vascularization is affected and both irregular vessel density and luminal thickening and thrombosis reduce what we have first identified as endometrial flow reserve. Finally, incorrect uterine wave propagation could affect embryo contact with decidua.
CONCLUSION
This is the first summary of evidence on CE pathophysiology and its relationship with infertility. Understanding the CE pathophysiology could improve our knowledge in embryo transfer success.
Topics: Chronic Disease; Embryo Implantation; Endometritis; Female; Fertilization in Vitro; Humans; Infertility, Female; Pregnancy; Pregnancy Rate
PubMed: 33025403
DOI: 10.1007/s10815-020-01955-8 -
BioMed Research International 2020Preeclampsia (PE) is termed as a systemic disease that involves multiple organs; however, the exact etiology is still quite unclear. It is believed that the poor...
Preeclampsia (PE) is termed as a systemic disease that involves multiple organs; however, the exact etiology is still quite unclear. It is believed that the poor remodeling of uterine spiral arteries triggers PE, thereby causing failed placentation and producing inflammatory factors. The decline of blood flow results in lowering the nutrients and oxygen received by the fetus and augmenting the placental pressure in PE. Decidual immune cells, especially uterine natural killer (uNK) cells, are involved in the process of placentation. Decidual NK (dNK) cells significantly contribute to the vascular remodeling through the secretion of cytokines and angiogenic mediators in normal placental development. The abnormal activation of NK cells in both the peripheral blood and the decidua was counted among the causes leading to PE. The correlation existing between maternal killer cell immunoglobulin-like receptor (KIR) and HLA-C in trophoblast cells constitutes a robust evidence for the genetic etiology of PE. The combinations of the two kinds of gene systems, together with the KIR genotype in the mother and the HLA-C group in her fetus, are likely to exactly decide the pregnancy outcome. The women, who have the inappropriate match of KIR/HLA-C, are likely to be prone to the augmented risk of PE. However, the combinations of KIR/HLA-C in PE undergo ethnic changes. The extensive prospective research works in Europe, Asia, and Africa are required for providing more findings in PE patients.
Topics: Animals; Female; Fetus; Genotype; HLA-C Antigens; Humans; Killer Cells, Natural; Pre-Eclampsia; Pregnancy; Receptors, KIR; Trophoblasts; Uterine Artery; Uterus
PubMed: 32309433
DOI: 10.1155/2020/4808072 -
Journal of Reproductive Immunology Jun 2020Regulatory T cells (Tregs) are essential in tolerizing the maternal immune system toward the semi-allogeneic embryo. In this systematic review, we evaluated the...
Regulatory T cells (Tregs) are essential in tolerizing the maternal immune system toward the semi-allogeneic embryo. In this systematic review, we evaluated the association of levels and function of Tregs in peripheral blood and decidua with recurrent miscarriage (RM), defined as two unexplained miscarriages. We included 18 studies. Ten studies showed a significantly decreased level of Tregs in peripheral blood of non-pregnant women with RM, compared to controls (p < 0.05). In pregnant women with RM, levels of Tregs in the peripheral blood were significantly lower compared to control groups (p = 0.0004), as shown in nine studies. Moreover, seven studies described a decrease of Treg levels in the placenta of pregnant women with RM (p < 0.0001) compared to controls. Accordingly, the median of the relative changes (MRC) between cases and controls in the non-pregnant group (peripheral blood), and the two pregnant groups (peripheral blood and decidua) were -0.18 (-0.27-0), -0.26 (-0.35 to -0.17), and -0.52 (0.63--0.31), respectively. In addition to the assessment of Tregs by phenotype, six out of the 18 included studies investigated the functionality of these cells. These studies showed a lower inhibitory effect of Tregs cells on the proliferation of effector T cells of women with RM compared to fertile women. Also, the expression of IL-10 and TGF-beta was diminished. This systematic review shows that Treg levels and their function are significantly decreased in peripheral blood and decidua of pregnant and non-pregnant women with RM. This underlines the hypothesis that Tregs play a role in the pathogenesis of RM.
Topics: Abortion, Habitual; Female; Forkhead Transcription Factors; Humans; Immune Tolerance; Interleukin-10; Placenta; Pregnancy; T-Lymphocytes, Regulatory; Transforming Growth Factor beta
PubMed: 32199194
DOI: 10.1016/j.jri.2020.103105 -
The Cochrane Database of Systematic... Jul 2019Fetal fibronectin (FFN) is an extracellular matrix glycoprotein localized at the maternal-fetal interface of the amniotic membranes, between chorion and decidua, where...
BACKGROUND
Fetal fibronectin (FFN) is an extracellular matrix glycoprotein localized at the maternal-fetal interface of the amniotic membranes, between chorion and decidua, where it is concentrated in this area between decidua and trophoblast. In normal conditions, FFN is found at very low levels in cervicovaginal secretions. Levels greater than or equal to 50 ng/mL at or after 22 weeks have been associated with an increased risk of spontaneous preterm birth. In fact, FFN is one of the best predictors of preterm birth in all populations studied so far, and can help in selecting which women are at significant risk for preterm birth. This is an update of a review first published in 2008.
OBJECTIVES
To assess the effectiveness of management based on knowledge of FFN testing results for preventing preterm birth.
SEARCH METHODS
For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register (7 September 2018), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (7 September 2018), and reference lists of retrieved studies.
SELECTION CRITERIA
Randomized controlled trials of pregnant women screened with FFN for risk of preterm birth. Studies included are based exclusively on knowledge of FFN results versus no such knowledge, and we have excluded studies including women with only positive or only negative FFN results.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed trials for inclusion and risk of bias, extracted data, and checked them for accuracy. The quality of the evidence was assessed using the GRADE approach.
MAIN RESULTS
We identified 16 trials, of which six were eligible for inclusion. The six included studies randomized 546 women with singleton gestations and threatened preterm labor (PTL) at 23 0/7 to 34 6/7 weeks. A total of 277 women were randomized to knowledge and 269 to no knowledge of FFN. No trials were identified on asymptomatic women or multiple gestations.The risk of bias of included studies was mixed. For selected important outcomes, preterm birth before 37, 34, and 32 weeks, and maternal hospitalization, we graded the quality of the evidence and created a 'Summary of findings' table. For these outcomes, the evidence was graded as mainly low quality due to the imprecision of effect estimates.Management based on knowledge of FFN results may reduce preterm birth before 37 weeks (21.6%) versus controls without such knowledge (29.2%) (risk ratio (RR) 0.72, 95% confidence interval (CI) 0.52 to 1.01; 4 trials; 357 women; low-quality evidence). However, management based on knowledge of FFN results may make little or no difference to preterm birth before 34 (RR 1.09, 95% CI 0.54 to 2.18; 4 trials; 357 women; low-quality evidence) or maternal hospitalization (RR 1.06, 95% CI 0.79 to 1.43; 5 trials; 441 women; low-quality evidence). The evidence for preterm birth before 32 weeks is uncertain because the quality was found to be very low (average RR 0.79, 95% CI 0.16 to 3.96; 4 trials; 357 women; very low-quality evidence).For all other outcomes, for which there were available data (preterm birth less than 28 weeks; gestational age at delivery (weeks); birthweight less than 2500 g; perinatal death; tocolysis; steroids for fetal lung maturity; time to evaluate; respiratory distress syndrome; neonatal intensive care unit (NICU) admission; and NICU days), knowledge of FFN results may make little or no difference to the outcomes.
AUTHORS' CONCLUSIONS
The evidence from this review suggests that management based on knowledge of FFN results may reduce preterm birth before 37 weeks. However, our confidence in this result is limited as the evidence was found to be of low quality. Effects on other substantive outcomes are uncertain due to serious concerns in study design, inconsistency, and imprecision of effect estimates. No trials were identified on asymptomatic women, or multiple gestations.Future studies are needed that include specific populations (e.g. singleton gestations with symptoms of preterm labor), a study group managed with a protocol based on the FFN results, and that report not only maternal but also important perinatal outcomes. Cost-effectiveness analyses are also needed.
Topics: Biomarkers; Female; Fibronectins; Gestational Age; Humans; Infant, Newborn; Obstetric Labor, Premature; Pregnancy; Premature Birth; Randomized Controlled Trials as Topic; Respiratory Distress Syndrome, Newborn
PubMed: 31356681
DOI: 10.1002/14651858.CD006843.pub3 -
The Journal of Maternal-fetal &... Jun 2020Multiple factors and pathways have been reported as critical machineries for cell differentiation and survival during pregnancy; a number of them involve glycogen...
Multiple factors and pathways have been reported as critical machineries for cell differentiation and survival during pregnancy; a number of them involve glycogen synthase kinase (GSK) 3a/β. Several reports on GSK3's functional role exist; however, the specific role of GSK3 in reproductive tissues and its contribution to normal or abnormal parturition are still unclear. To fill this knowledge gap, a systematic review of literature was conducted to better understand the functional role of GSK3 in various intrauterine tissues during implantation, pregnancy, and parturition. We conducted a systematic review of literature on GSK3's expression and function reported between 1980 and 2017 in reproductive tissues during pregnancy using three electronic databases (Web of Science, Medline, and ClinicalTrials.gov). Study selection, data extraction, quality assessment and analyses were performed in duplicate by two independent reviewers. A total of 738 citations were identified; 80 were selected for full text evaluation and 25 were included for final review. GSK3's regulation and function were mostly studied in tissues and cells from placentas (12), fetuses (8), uteruses (6), and ovaries (2). GSK3 is primarily reported as a downstream responder of protein kinase B (AKT)-, Wnt-, and reactive oxygen species (ROS)-related pathways where it plays a critical role in cell survival and growth in reproductive tissues. Though GSK3 has been functionally linked to a number of biological processes in reproductive tissues, it has primarily been studied as a secondary signaler of various conserved cell signaling pathways. Lack of scientific rigor in studying GSK3's role in reproductive tissues makes this molecule's function still obscure. No studies have reported GSK3 in the cervix, and very few reports exist in myometrium and decidua. This systematic review suggests more functional and mechanistic studies focusing on GSK3 need to be conducted in reproductive biology.
Topics: Biomarkers; Female; Glycogen Synthase Kinase 3; Humans; Parturition; Pregnancy
PubMed: 30278798
DOI: 10.1080/14767058.2018.1531843 -
American Journal of Reproductive... Dec 2018Oxidative stress (OS) plays a role in uterine tissue remodeling during pregnancy and parturition. While p38 MAPK is an OS-response kinase, a precise functional role is...
Oxidative stress (OS) plays a role in uterine tissue remodeling during pregnancy and parturition. While p38 MAPK is an OS-response kinase, a precise functional role is unknown. Therefore, we conducted a systematic review of literature on p38 MAPK expression, activation, and function in reproductive tissues throughout pregnancy and parturition, published between January 1980 and August 2017, using four electronic databases (Web of Science, PubMed, Medline, and CoCHRANE). We identified 418 reports; 108 were selected for full-text evaluation and 74 were included in final review. p38 MAPK was investigated using feto-maternal primary or immortalized cells, tissue explants, and animal models. Western blot was most commonly used to report phosphorylated (active) p38 MAPK. Human placenta (27), chorioamniotic membranes (14), myometrium (13), decidua (8), and cervix (1) were the studied tissues. p38 MAPK's functions were tissue and gestational age dependent. Isoform specificity was hardly reported. p38 MAPK activity was induced by ROS or proinflammatory cytokines to promote cell signaling linked to cell fate, primed uterus, ripened cervix, and proinflammatory cytokine/chemokine production. In 35 years, reports on p38 MAPK's role during pregnancy and parturition are scarce and current literature is insufficient to provide a comprehensive description of p38 MAPK's mechanistic role during pregnancy and parturition.
Topics: Animals; Disease Models, Animal; Female; Gene Expression Regulation; Genitalia, Female; Humans; Inflammation; Oxidative Stress; Parturition; Pregnancy; Reproduction; Signal Transduction; p38 Mitogen-Activated Protein Kinases
PubMed: 30178469
DOI: 10.1111/aji.13047 -
American Journal of Reproductive... Feb 2018Parturition at term is characterized by inflammatory overload in both feto-maternal tissues. Despite the large number of individual studies on changes in inflammatory... (Review)
Review
Parturition at term is characterized by inflammatory overload in both feto-maternal tissues. Despite the large number of individual studies on changes in inflammatory biomarkers linked to labor, a comprehensive profile of them in each of the uterine compartments is not available to better understand their mechanistic contributions to labor. This systematic review investigated the pro- and anti-inflammatory biomarkers reported in intra-uterine tissues (amnion, chorion, decidua, placenta, and myometrium) at term labor. We conducted a systematic review of studies on pro- and anti-inflammatory biomarkers (mRNA and/or protein) reported in feto-maternal tissues during normal human term labor, published in English (1980-2016), in 3 electronic data bases. From a total of 3712 citations, 172 were included for final review. Each tissue expresses a unique set of biomarkers at the time of term labor, but there is significant overlap between tissues. All tissues had IL-6, IL-8, IL-1β, COX-2, PGE-2, TNF-α, and hCAP18 in common at term labor. Common and unique inflammatory biomarkers are expressed in various feto-maternal compartments at term labor. Increase in pro-inflammatory markers in all gestational tissue signifies their harmonious functional role in promoting labor. Anti-inflammatory markers at term labor are hardly reported.
Topics: Animals; Antimicrobial Cationic Peptides; Biomarkers; Cathelicidins; Cyclooxygenase 2; Female; Humans; Inflammation; Inflammation Mediators; Metalloporphyrins; Parturition; Pregnancy; Uterus
PubMed: 29076197
DOI: 10.1111/aji.12776 -
BMC Medical Genomics Jun 2015Preterm birth (PTB), or birth before 37 weeks of gestation, is the leading cause of newborn death worldwide. PTB is a critical area of scientific study not only due to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Preterm birth (PTB), or birth before 37 weeks of gestation, is the leading cause of newborn death worldwide. PTB is a critical area of scientific study not only due to its worldwide toll on human lives and economies, but also due to our limited understanding of its pathogenesis and, therefore, its prevention. This systematic review and meta-analysis synthesizes the landscape of PTB transcriptomics research to further our understanding of the genes and pathways involved in PTB subtypes.
METHODS
We evaluated published genome-wide pregnancy studies across gestational tissues and pathologies, including those that focus on PTB, by performing a targeted PubMed MeSH search and systematically reviewing all relevant studies.
RESULTS
Our search yielded 2,361 studies on gestational tissues including placenta, decidua, myometrium, maternal blood, cervix, fetal membranes (chorion and amnion), umbilical cord, fetal blood, and basal plate. Selecting only those original research studies that measured transcription on a genome-wide scale and reported lists of expressed genetic elements identified 93 gene expression, 21 microRNA, and 20 methylation studies. Although 30 % of all PTB cases are due to medical indications, 76 % of the preterm studies focused on them. In contrast, only 18 % of the preterm studies focused on spontaneous onset of labor, which is responsible for 45 % of all PTB cases. Furthermore, only 23 of the 10,993 unique genetic elements reported to be transcriptionally active were recovered 10 or more times in these 134 studies. Meta-analysis of the 93 gene expression studies across 9 distinct gestational tissues and 29 clinical phenotypes showed limited overlap of genes identified as differentially expressed across studies.
CONCLUSIONS
Overall, profiles of differentially expressed genes were highly heterogeneous both between as well as within clinical subtypes and tissues as well as between studies of the same clinical subtype and tissue. These results suggest that large gaps still exist in the transcriptomic study of specific clinical subtypes as well in the generation of the transcriptional profile of well-studied clinical subtypes; understanding the complex landscape of prematurity will require large-scale, systematic genome-wide analyses of human gestational tissues on both understudied and well-studied subtypes alike.
Topics: DNA Methylation; Female; Gene Expression Profiling; Gene Expression Regulation, Developmental; Genome-Wide Association Study; Humans; Phenotype; Placenta; Pregnancy; Premature Birth; Risk Factors; Term Birth; Transcriptome
PubMed: 26044726
DOI: 10.1186/s12920-015-0099-8 -
Ultrasound in Obstetrics & Gynecology :... Aug 2015To evaluate the diagnostic accuracy of ultrasound in predicting the location of an intrauterine pregnancy before visualization of the yolk sac is possible. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To evaluate the diagnostic accuracy of ultrasound in predicting the location of an intrauterine pregnancy before visualization of the yolk sac is possible.
METHODS
This was a systematic review conducted in accordance with the PRISMA statement and registered with PROSPERO. We searched MEDLINE, EMBASE and The Cochrane Library for relevant citations. Studies were selected in a two-stage process and their data extracted by two reviewers. Accuracy measures were calculated for each ultrasound sign, i.e. gestational sac, double decidual sac sign, intradecidual sign, chorionic rim sign and yolk sac. Individual study estimates were plotted in summary receiver-operating characteristics curves and forest plots for examination of heterogeneity. The quality of included studies was assessed.
RESULTS
Seventeen studies including 2564 women were selected from 19 959 potential papers. Following meta-analysis, the presence of a gestational sac on ultrasound examination was found to predict an intrauterine pregnancy with a sensitivity of 52.8% (95% CI, 38.2-66.9%) and specificity of 97.6% (95% CI, 94.3-99.0%). The corresponding performance of the double decidual sac sign, intradecidual sign, chorionic rim sign and yolk sac were: 81.8% (95% CI, 68.1-90.4%) and 97.3% (95% CI, 76.1-99.8%); 66.1% (95% CI, 58.9-72.8%) and 100% (95% CI, 91.0-100%); 79.9% (95% CI, 73.0-85.7%) and 97.1% (95% CI, 89.9-99.6%); and 42.2% (95% CI, 27.7-57.9%) and 100% (95% CI, 54.1-100%), respectively.
CONCLUSION
Visualization of a gestational sac, double decidual sac sign, intradecidual sign or chorionic rim sign increases the probability of an intrauterine pregnancy but is not as accurate for diagnosis as the detection of the yolk sac. However, the findings were limited by the small number and poor quality of the studies included and heterogeneity in the index test and reference standard.
Topics: Decidua; Female; Gestational Sac; Humans; Pregnancy; Pregnancy Trimester, First; Pregnancy, Ectopic; Ultrasonography, Prenatal; Yolk Sac
PubMed: 25393076
DOI: 10.1002/uog.14725