Recurrent Pregnancy Loss Patients Research Articles

Investigating into microbiota in the uterine cavity of the unexplained recurrent pregnancy loss patients in early pregnancy

IntroductionThe majority of unexplained recurrent pregnancy loss (URPL) cases have been attributed to immune abnormalities. Inappropriate changes in microbiota could lead to immune disorders. However, the specific role of uterine cavity microbiota in URPL remains unclear, and only a limited number of related studies are available for reference. MethodsWe utilized double-lumen embryo transfer tubes to collect uterine cavity fluid samples from pregnant women in their first trimester. Subsequently, we conducted 16S rRNA sequencing to analyze the composition and abundance of the microbiota in these samples. ResultsFor this study, we enlisted 10 cases of URPL and 28 cases of induced miscarriages during early pregnancy. Microbial communities were detected in all samples of the URPL group (100 %, n = 10), whereas none were found in the control group (0 %, n = 28). Among the identified microbes, Lactobacillus and Curvibacter were the two most dominant species. The abundance of Curvibacter is correlated with the number of NK cells in peripheral blood (r = −0.759, P = 0.018). DiscussionThis study revealed that during early pregnancy, Lactobacillus and Curvibacter were the predominant colonizers in the uterine cavity of URPL patients and were associated with URPL. Consequently, alterations in the dominant microbiota may lead to adverse pregnancy outcomes.

Immunological Indicators of Recurrent Pregnancy Loss: A Mendelian Randomization Study.

Recurrent pregnancy loss (RPL) is thought to be related to maternal-fetal immune tolerance disorders. Immune monitoring of RPL patients mainly involves two aspects: inflammatory factors and immune cells. However, most observational studies have reported controversial findings. This study aimed to confirm whether abnormal inflammatory factors and immune cells in peripheral blood may lead to RPL, and guide clinical immune monitoring. We demonstrated causality using two-sample Mendelian randomization. Sensitivity analysis, reverse Mendelian randomization and meta-analysis were used to enhance the effectiveness of the results. There was a causal relationship between the level of IL-12 (OR = 1.78, 95% CI = 1.25-2.55; P = 0.00149) and RPL for 41 inflammatory factors. We screened 5 groups of immune cell subtypes that were causally associated with RPL: switched memory B-cell absolute count (OR = 0.66, 95% CI = 0.49-0.87, P = 0.00406), IgD + CD24 + B-cell absolute count (OR = 0.69, 95% CI = 0.53-0.88, P = 0.00319), CD39 + resting CD4 regulatory T-cell %CD4 regulatory T-cell (OR = 0.86, 95% CI = 0.78-0.95, P = 0.00252), activated & resting CD4 regulatory T-cell %CD4 regulatory T-cell (OR = 0.89, 95% CI = 0.82-0.97, P = 0.00938) and CD45 RA + CD28-CD8 + T-cell %CD8 + T-cell (OR = 0.99, 95% CI = 0.98-1.00, P = 0.01231). In terms of inflammatory factors, a causal relationship between IL-12 and RPL in peripheral blood was confirmed. We also identified five immune cell phenotypes that play a protective role. This suggests that there may be protective B cells and CD8 + T-cell subsets in peripheral blood, and the protective effect of Tregs was proved again. Immune monitoring of peripheral blood in patients with RPL seems to be necessary and the foundation for precision medicine.

Frequency of Gene Polymorphisms in Admixed Venezuelan Women with Recurrent Pregnancy Loss: Microsomal Epoxy Hydroxylase (rs1051740) and Enos (rs1799983).

Recurrent pregnancy loss (RPL) affects around 2% of women of reproductive age. Primary RPL is defined by ≥2 pregnancy losses and no normal birth delivery. In secondary RPL, the losses are after a normal pregnancy and delivery. Most cases have no clear aetiology, although primary cases are the most complex. Several gene single nucleotide polymorphisms (SNPs) have been associated with RPL. The frequency of some SNPs is increased in women suffering from RLP from Asian or Caucasian races; however, in admixed populations, the information on possible genetic links is scarce and contradictory. This study aimed to assess the frequency of two SNPs present in two different enzymes involved in medical conditions observed during pregnancy. It is a case-control study. Microsomal epoxy hydrolase (mEPH) is involved in detoxifying xenobiotics, is present in the ovaries, and is hormonally regulated. The endothelial nitric oxide synthase (NOS3) that forms nitric is involved in vascular tone. Two SNPs, rs1051740 (mEPH) and rs1799983 (NOS3), were assessed. The study included 50 controls and 63 primary RPL patients. The frequency of mutated alleles in both SNPs was significantly higher in patients (p < 0.05). Double-mutated homozygotes were encountered only in RPL patients (p < 0.05). Genetic polymorphisms rs1051740 and rs1799983 may be involved in primary RPL in the Venezuelan admix population. Genetic studies could provide crucial information on the aetiology of primary RPL.

The risk of sexual dysfunction in Chinese women with recurrent pregnancy loss and the associated factors: a multicenter cross-sectional study.

Recurrent pregnancy loss (RPL) is a severe traumatic event for women of childbearing age. However, the association between RPL and female sexual dysfunction was unknown. The study sought to investigate the association between RPL and sexual dysfunction, and to explore the risk factors of sexual dysfunction for RPL patients. A multicenter cross-sectional study involving both RPL patients and healthy women was performed in 3 different hospitals in West China from May 2021 to January 2023. Baseline information including sociodemographic data and disease histories were collected. The Female Sexual Function Index (FSFI) was used to assess the sexual function of participants. The main outcome was the proportion of women at increased risk of sexual dysfunction (total FSFI scores <26.55), and the secondary outcome was risk factors of sexual dysfunction in RPL patients. A total of 233 RPL patients and 185 healthy women were included in this study. RPL patients had significantly lower total FSFI scores (median 31.7 [interquartile range, 26.6-33.5] vs 33.0 [interquartile range, 31.2-34.1]; P < .001) and a significantly higher risk of sexual dysfunction than healthy women (24.9% vs 8.6%; P < .001). Body mass index >24 kg/m2 (adjusted odds ratio [OR], 4.132; 95% confidence interval [CI], 1.902-8.976, P < .001), working >8 h/d (adjusted OR, 2.111; 95% CI, 1.020-4.369, P = .044), and unexplained RPL (adjusted OR, 3.785; 95% CI, 1.967-7.280, P < .001) were independent risk factors of sexual dysfunction for RPL patients. RPL patients, especially those patients with the previously mentioned risk factors, should be focused on the risk of sexual dysfunction, and appropriate preventions could be applied. We explored the association between RPL and sexual dysfunction and explored the risk factors of sexual dysfunction among RPL patients for the first time, and the multicenter data increased the generalizability of results. However, the cross-sectional design did not provide an exact causal relationship between RPL and sexual dysfunction, and potential risk factors related to mental health were not investigated. RPL patients were at an increased risk of sexual dysfunction. Overweight, fatigue caused by work, and unexplained RPL were risk factors of sexual dysfunction for RPL patients.

Immunological Risk Factors in Recurrent Pregnancy Loss in Patients With Hereditary Thrombophilia.

Recurrent pregnancy loss (RPL) is a complicated reproductive disorder with underlying genetic and immunological causes. RPL may be influenced by hereditary thrombophilia, a class of blood clotting-related genetic abnormalities, via the vascular and immune systems. This study examines the immunological characteristics that hereditary thrombophilia patients have in common with RPL. A prospective cohort study included 300 patients split into two groups: a control group without hereditary thrombophilia and a group with the condition. Interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ)levels were measured, along with demographic specifics, antiphospholipid antibodies, natural killer (NK) cell counts, and other cytokines. Group differences were found using statistical analysis. Antiphospholipid antibodies were significantly more common in the thrombophilia group (42% testing positive, p=0.001) compared to the control group (12% testing positive), despite demographic factors being similar between groups (p=0.372 and p=0.093).When body mass index (BMI) was taken into account, the studyfound a statistically significant difference (p=0.046), with the thrombophilia group having a higher mean BMI (26.3 kg/m2, standard deviation (SD): 2.8) than the control group (24.7 kg/m2, SD: 3.1). IL-6(14.8 pg/mL, SD: 3.2, p=0.029) were higher than the control group (12.4 pg/mL,SD: 2.1), and TNF-α levels were higher in the thrombophilia group (10.5 pg/mL, SD: 2.0, p=0.012) compared to the control group (8.9 pg/mL,SD: 1.5), but NK cell counts did not differ significantly (p=0.213). This study emphasizes the role of elevated pro-inflammatory cytokines (IL-6 and TNF-α) and antiphospholipid antibodies in RPL among people with hereditary thrombophilia. In this population, early detection and immunomodulatory interventions may improve pregnancy outcomes. To fully comprehend these mechanisms and create customized treatments, collaborative research is required.

Unlocking the Uterine Code: Microbiota, Immune Cells, and Therapy for Recurrent Reproductive Failure.

The uterine microbiota has been the subject of increasing study, but its interaction with the local immune system remains unclear. Successful embryo implantation relies on endometrial receptivity, which is pivotal for immunological tolerance to fetal antigens and precise regulation of inflammatory mediators. Emerging data suggest a dynamic interplay between endometrial microflora and the immune system, making dysbiosis a potential determinant of pregnancy outcomes. Imbalances in the regulation of immune cells in the endometrium and decidua have been associated with infertility, miscarriage, and obstetric complications. A thorough comprehension of the immune system in the female reproductive tract shows potential for improving women's health and pregnancy outcomes. The objective of this study was to evaluate the patterns of endometrial microbiota in patients with recurrent implantation failure (RIF) and recurrent pregnancy loss (RPL) and to explore their implications for endometrial immune cells and chronic endometritis (CE). Immune cells in biopsies from 107 RIF and 93 RPL patients were examined using flow cytometry. The endometrial microbial composition was analyzed using real-time polymerase chain reaction (RT-PCR). The research uncovered disrupted endometrial microbiota in most women with RIF and RPL, which was often associated with significant effects on lymphocytes, T cells, and uNK cells.

Predicting risk of subsequent pregnancy loss among women with recurrent pregnancy loss: An immunological factor-based multivariable model.

Studies on subsequent pregnancy loss prediction models specific for recurrent pregnancy loss (RPL) patients are very limited. This study aims to develop a risk predictive model based on the immunological parameters for the subsequent pregnancy loss risk in northwest Chinese RPL patients. Totally of 357 RPL patients recruited from Lanzhou University Second Hospital were included in this retrospective study. Univariate analysis was performed on RPL patients with outcomes of live birth or pregnancy loss. Subsequently, the least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression were utilized to select variables among baseline and clinical characteristics and to develop a pregnancy loss risk prediction model with all 357 RPL patients. The area under the curve (AUC), calibration curve and decision curve analyses were used to evaluate the performance of the prediction model; moreover, 10-fold cross-validation was used for internal validation. Ten factors of maternal age, age of menarche, previous pregnancy loss, IL-10, complement 4, IgA, antiprothrombin antibody IgG/IgM, rheumatoid factor IgA, and lupus anticoagulant (LA) 1/LA2 ratio were finally selected as variables for the prediction model of pregnancy loss risk. The AUC value and Hosmer-Lemeshow test p-value of the model were.707 and.599, respectively, indicating a satisfactory discrimination and calibration performance. Moreover, the clinical decision curve suggested this prediction model have a good positive net benefit. This is the first prediction model for the risk of subsequent pregnancy loss in northwest Chinese women with RPL, providing a user-friendly tool to clinicians for the early prediction and timely management of RPL patients.

Diagnostic value of neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio to predict recurrent pregnancy loss and abortion; a systematic review and meta-analysis.

This systematic review and meta-analysis aimed to evaluate the diagnostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in women with a history of abortion (missed and threatened) and recurrent pregnancy loss (RPL) in comparison with healthy pregnancies. Electronic databases including MEDLINE, Scopus, Web of Science, Embase, and Cochrane Library were searched for NLR and PLR in women who experienced early pregnancy loss up to January 1, 2023 with a combination of proper keywords. Meta-analysis was done for comparison with three or more studies and summary estimates were measured. A total of 390 citations were retrieved initially, and after screening, 16 articles were deemed eligible for the final review. Among these, 14 studies underwent meta-analysis. The meta-analysis revealed that the standard mean of the NLR was significantly higher in abortion cases compared to the control group. However, there was no significant difference in the PLR between the pregnancy loss group and the control group. NLR was significantly higher among RPL patients compared to the control group, according to these data, NLR may be capable of being used in the diagnosis of RPL as an easy, cheap, and accessible modality. Further studies, which take these variables into account, will need to be undertaken to determine the diagnostic value of NLR and PLR in early pregnancy loss.

A history of recurrent pregnancy loss is associated with increased perinatal complications, but not necessarily a longer birth interval: a population study spanning 18 years.

Is there a difference in the time interval between the first and second live births among individuals with and without recurrent pregnancy loss (RPL)? Primary RPL (two or more pregnancy losses before the first live birth) is associated with a shorter time interval between the first and second live births compared with individuals without RPL, but this association is reversed in patients with secondary RPL (RPL patients with no or one pregnancy loss before the first live birth). There is limited information regarding the ability to have more than one child for patients with RPL. Previous studies have investigated the time to live birth and the live birth rate from the initial presentation to clinical providers. Most of the previous studies have included only patients treated at specialized RPL clinics and thus may be limited by selection bias, including patients with a more severe condition. We conducted a population-based retrospective cohort study of 184241 participants who delivered in British Columbia, Canada, and had at least two recorded live births between 2000 and 2018. The aim was to study the differences in the time interval between the first and second live births and the prevalence of pregnancy complications in patients with and without RPL. Additionally, 198319 individuals with their first live birth between 2000 and 2010 were studied to evaluate cumulative second live birth rates. Among individuals with at least two recorded live births between 2000 and 2018, 12321 patients with RPL and 171920 participants without RPL were included. RPL was defined as at least two pregnancy losses before 20 weeks gestation. Patients with primary RPL had at least two pregnancy losses occurring before the first live birth, while patients with secondary RPL had no or one pregnancy loss before the first live birth. We compared the time interval from the first to second live birth in patients with primary RPL, those with secondary RPL, and participants without RPL using generalized additive models to allow for a non-linear relationship between maternal age and time interval between first and second live births. We also compared prevalence of pregnancy complications at the first and second live births between the groups using non-parametric Kruskal-Wallis H test and Fisher's exact test for continuous and categorical variables, respectively. We assessed the cumulative second live birth rates in patients with primary RPL and those without RPL, among participants who had their first live birth between 2000 and 2010. Cox proportional hazards model was used to estimate and compare hazard ratios between the two groups using a stratified modelling approach. The adjusted time interval between the first and second live births was the longest in patients with secondary RPL, followed by individuals without RPL, and the shortest time interval was observed in patients with primary RPL: 4.34 years (95% CI: 4.09-4.58), 3.20 years (95% CI: 3.00-3.40), and 3.05 years (95% CI: 2.79-3.32). A higher frequency of pregnancy losses was associated with an increased time interval between the first and second live births. The prevalence of pregnancy complications at the first and second live births, including gestational diabetes, hypertensive disorder of pregnancy, preterm birth, and multiple gestations was significantly higher in patients with primary RPL compared with those without RPL. The cumulative second live birth rate was significantly lower in patients with primary RPL compared with individuals without RPL. This study may be limited by its retrospective nature. Although we adjusted for multiple potential confounders, there may be residual confounding due to a lack of information about pregnancy intentions and other factors, including unreported pregnancy losses. The results of this study provide information that will help clinicians in the counselling of RPL patients who desire a second child. This study was supported in part by a grant from the Canadian Institutes of Health Research (CIHR): Reference Number W11-179912. M.A.B. reports research grants from CIHR and Ferring Pharmaceutical. He is also on the advisory board for AbbVie, Pfizer, and Baxter. The other authors report no conflict of interest. NCT04360564.

Deciphering molecular basis of pesticide-induced recurrent pregnancy loss: insights from transcriptomics analysis

Recent studies have revealed a notable connection between pesticide exposure and Recurrent Pregnancy Loss (RPL), yet the precise molecular underpinning of this toxicity remains elusive. Through the alignment of Differentially Expressed Genes (DEGs) of healthy and RPL patients with the target genes of 9 pesticide components, we identified a set of 12 genes responsible for RPL etiology. Interestingly, biological process showed that besides RPL, those 12 genes also associated with preeclampsia and cardiovascular disease. Enrichment analysis showed the engagement of these genes associated with essential roles in the molecular transport of small molecules, as well as the aldosterone-regulated sodium reabsorption, endocrine and other factor-regulated calcium reabsorption, mineral absorption, ion homeostasis, and ion transport by P-type ATPases. Notably, the crosstalk targets between pesticide components played crucial roles in influencing RPL results, suggesting a role in attenuating pesticide agents that contribute to RPL. It is important to note that non-significant concentration of the pesticide components observed in both control and RPL samples should not prematurely undermine the potential for pesticides to induce RPL in humans. This study emphasizes the complexity of pesticide induced RPL and highlights avenues for further research and precautionary measures.

The evaluation of PD-1 and Tim-3 expression besides their related miRNAs in PBMCs of women with recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a multifactorial disorder, associated with immunologic abnormalities. During pregnancy, the maternal immune system uses different tolerance mechanisms to deal with a semi-allogenic fetus. The expression of immune checkpoints and their related miRNAs in immune cells can ensure pregnancy at the feto-maternal interface by modulating immune responses. This study aims to evaluate the expression of the immune checkpoint molecules PD-1 and Tim-3 on circulating T cells by flow cytometry, that of mir-138 and mir-155 in PBMCs by Real-time PCR, and the concentrations of TGF-β and IP-10 in the sera of women suffering from RPL as well as of gestational age-matched healthy pregnant women by ELISA. The percentage of PD-1 or Tim-3 expressing CD8+ T cells was significantly lower in RPL patients compared to the controls, while there was no significant difference in Tim-3 expression of CD4+ T cells between the two groups. The mRNA of both the PD-1 and Tim-3 genes were downregulated in PBMCs of RPL patients compared to controls, however, the difference was not statistically significant for Tim-3. The concentration of TGF-β was significantly lower and that of IP-10 was significantly higher in the sera of RPL patients than in those of the controls. The relative expression of mir-138 and miR-155 were significantly lower, in PBMCs of RPL patients than in those of healthy pregnant women. These data confirm that by affecting cytokine production, immune checkpoints, and microRNAs play a role in establishing the appropriate local immune environment for successful pregnancy. The wider analysis of immune checkpoints may also yield new biomarkers for the diagnosis and prevention of RPL.

Vitamin D levels in non-pregnant women with a history of recurrent pregnancy loss with and without autoantibodies.

The objective of this study was to compare the levels of vitamin D in non-pregnant women with a history of recurrent pregnancy loss (RPL) who were seropositive or seronegative for autoantibodies (autoAbs). The study examined 58 RPL patients with autoAbs (ANA, anti-TPO, or APAs), 34 RPL patients without autoAbs, and 58 healthy women with prior successful pregnancies and without autoantibodies. The levels of 25 (OH) D were measured using the sandwich ELISA technique. Our results showed insufficient serum 25(OH) D levels in study groups, with significantly lower levels observed in RPL patients with or without autoAbs compared to healthy women (P=0.0006). In addition, RPL patients with autoAbs had significantly lower 25(OH) D levels compared to RPL patients without autoAbs. We also found that serum levels of 25(OH) D in RPL patients with autoAbs were significantly lower than in RPL patients without autoAbs (20.51 ± 1.15 ng/ml Vs. 23.69 ± 0.74 ng/ml, P=0.0356). Further analysis indicated that RPL patients who were positive for ANA, and APAs, except anti-TPO, had significantly lower than 25(OH)D serum levels than RPL patients without autoAbs. These findings suggest that RPL patients, especially those with APAs or ANA, have lower vitamin D levels compared to healthy women. This may indicate a link between maternal immune dysregulation due to vitamin D deficiency and the presence of autoantibodies in RPL.

PGT-A: What Is Its Value in Treating Recurrent Pregnancy Loss?

PGT has been widely applied in the world, but its effectiveness for the treatments of recurrent pregnancy loss is still inconclusive. There is currently no consensus over the precise definition of RPL, according to the ESHRE guideline in 2022, a diagnosis of Recurrent Pregnancy Loss (RPL) could be considered after the loss of two or more pregnancies. The etiology of RPL is complex and highly heterogeneous, the higher proportion of embryo aneuploidy is an important reason, which can be affected significantly by maternal age. RPL has been listed as one of the common indications for PGT-A worldwide. However, the new RPL guideline by EHSRE in 2022, indicated that limited evidence for PGT in couples with RPL shows no clear benefit of treatment with very low quality. We reviewed the published studies, three retrospective studies showed that PGT-A may improve live birth rate for RPL patients, while two studies showed negative results. Most importantly, there were no randomized studies published on the application of PGT-A among RPL couples. Our data also showed similar cumulative live birth rates between PGT-A group and the control, regardless of maternal age, but PGT-A may favour in reducing miscarriage recurrence risk for RPL couples over 37 years old who obtained transferrable embryos. The presence of mosaic embryos and false positive/negative results, which can cause a high rate of cycle cancellation, may be the main reasons that compromise the efficacy of PGT-A. The cost-effectiveness of PGT-A is another important concern. In conclusion, there is still no sufficient evidence to support whether PGT-A can effectively improve the pregnancy outcomes for RPL couples, and proper-designed RCT is required in the future.

Downregulation of CRHBP is associated with trophoblast invasion inhibition in recurrent pregnancy loss.

Corticotropin-releasing hormone binding protein (CRHBP) is fundamental to the stress response and plays an important role in parturition during pregnancy. This study shows that abnormal CRHBP expression could be an early warning sign of recurrent pregnancy loss and that CRHBP knockdown could suppress HTR8/SVneo cell invasion by the PKC signaling pathway via interacting with CRH receptor 2. Trophoblast invasion is critical for placentation and pregnancy success. Trophoblast dysfunction results in many pregnancy complications, including recurrent pregnancy loss (RPL). Corticotropin-releasing hormone binding protein (CRHBP) is fundamental to the stress response and plays an important role in parturition during pregnancy via binding with CRH. To further characterize its function in early pregnancy, we explored the expression of CRHBP in villi during early pregnancy. Compared with normal pregnant women, we demonstrated that the expression of CRHBP decreased in the trophoblasts and villi in RPL patients and that knockdown of CRHBP expression could suppress HTR8/SVneo cell invasion significantly. Our further exploration indicated that the capacity of CRHBP for regulating trophoblast invasion was associated with the PKC signaling pathway via interacting with CRH receptor 2. These findings might provide a new fundamental mechanism for successful pregnancy and a new diagnostic and therapeutic target for RPL.

Intrauterine perfusion of dexamethasone improves pregnancy outcomes in recurrent reproductive failure patients with elevated uterine natural killer cells. A retrospective cohort study

AbstractObjectiveTo determine the effect of intrauterine perfusion of dexamethasone (DXM) on pregnancy outcomes in recurrent reproductive failure (RRF) patients with elevated uNK cells.MethodsThis retrospective cohort study included 132 RRF patients with elevated uNK cells: 56 patients received DXM treatment and 76 patients refused it in the frozen‐thawed embryo transfer cycles. To determine the efficacy of intrauterine perfusion of DXM, multivariate logistic regression models and diagnosis‐based subgroup analysis were performed. We also compared the pregnancy outcomes of patients with different responsiveness to DXM treatment.ResultsIntrauterine perfusion of DXM significantly improved clinical pregnancy rate (aOR: 3.188, 95% CI: 1.395–7.282, P = .006) and live birth rate (aOR: 3.176, 95% CI: 1.318–7.656, P = .010) in RRF patients with elevated uNK cells, but there was no significant association with miscarriage rate. Subgroup analysis revealed that intrauterine perfusion of DXM in patients with recurrent implantation failure (RIF) showed significant improvement in clinical pregnancy rate (aOR: 6.110, 95% CI: 1.511–24.713, P = .011) and live birth rate (aOR: 9.904, 95% CI: 1.963–49.968, P = .005), but there was insufficient evidence of benefit in recurrent pregnancy loss (RPL) patients. Additionally, uNK cell levels dropped to normal range was achieved in only 35.90% of RRF patients after DXM treatment, no significant difference was found in pregnancy outcomes among patients with different responsiveness to DXM treatment (all P &gt; .05).ConclusionIntrauterine perfusion of DXM was a promising and effective treatment to enhance clinical pregnancy rate and live birth rate in RRF women with abnormally elevated uNK cells, and RIF patients are more likely to benefit than RPL patients.

Identification of m6A Modification Regulated by Dysregulated circRNAs in Decidua of Recurrent Pregnancy Loss.

N6-methyladenosine (m6A) modification is a prevalent modification of messenger ribonucleic acid (mRNA) in eukaryote cells and is closely associated with recurrent pregnancy loss (RPL). Circular RNAs (circRNAs) play critical roles in embryo implantation, trophoblast invasion and immune balance, which are important events during pregnancy. However, how m6A modification is regulated by circRNAs and the potential regulatory mechanism of circRNAs on RPL occurrence remain largely unclassified. We displayed the expression profiles of circRNAs and mRNAs in the decidua of normal pregnancies and RPL patients based on circRNA sequencing and the Gene Expression Omnibus database. A total of 936 differentially expressed circRNAs were identified, including 509 upregulated and 427 downregulated circRNAs. Differentially expressed circRNAs were enriched in immune, metabolism, signaling and other related pathways via the analysis of Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. The competitive endogenous RNA (ceRNA) network was predicted to supply the possible role of circRNAs in RPL occurrence, and we further analyzed the profiles of nine m6A regulators (seven readers, one writer and one eraser) managed by circRNAs in this network. We also showed the expression profiles of circRNAs in the serum, trying to seek a potential biomarker to help in the diagnosis of RPL. These data imply that circRNAs are involved in pathogenesis of RPL by changing immune activities, metabolism and m6A modification in the ceRNA network. Our study might provide assistance in exploring the pathogenesis and diagnosis of RPL.

Myeloid-derived suppressor cells as a potential biomarker for recurrent pregnancy loss and recurrent implantation failure: Increased levels of MDSCs in recurrent reproductive failure.

Recurrent pregnancy loss (RPL) and recurrent implantation failure (RIF) represent distinct clinical conditions with established definitions, both of which have been linked to an underlying pro-inflammatory state. This study aimed to explore the levels of monocytic-myeloid-derived suppressor cells (M-MDSCs) and regulatory T cells (TReg ) in a cohort of RPL and RIF women and their potential contribution to RPL and RIF. One hundred and eight non-pregnant women were evaluated: 40 RPL, 41 RIF, and 27 fertile healthy controls (HC). A multiparametric flow cytometry approach was utilized to measure and quantify the frequency of M-MDSCs and TReg cells. Cytokine levels in plasma samples were evaluated through a multiplex assay. M-MDSCs levels were significantly higher in RPL and RIF patients compared to HC. M-MDSCs levels were significantly higher in RPL (9.4% [7-11.6]) and RIF (8.1% [5.9-11.6]) patients compared to HC (6% [4.2-7.6]). An optimal cut-off of 6.1% for M-MDSCs disclosed a sensitivity of 75.6% and 89.7% and a specificity of 57.7% and 57.7% in RIF and RPL groups, respectively. A significant negative correlation was observed between M-MDSCs and TReg (p=.002, r=-.51). Our preliminary data allowed us to build a predictive model that may aid as a potential diagnostic tool in the clinic. These findings could provide a better understanding of these pathologies and a better definition of patients that could benefit from personalized treatments to promote pregnancy. Additional exploration and confirmation in distinct study groups are needed to fully assess the diagnostic capabilities of this biomarker.

Impaired decidualization and relative increase of PROK1 expression in the decidua of patients with unexplained recurrent pregnancy loss showing insulin resistance

A recent meta-analysis revealed that patients with unexplained recurrent pregnancy loss (RPL) show higher insulin resistance compared to healthy controls. However, the etiology of RPL remains unknown. Prokineticin (PROK1), a pleiotropic uterine endometrial protein, is important for implantation and decidualization and is regulated by hypoxia and insulin. In this study, we investigated the decidualization status and the role of PROK1 in the decidua of patients with unexplained RPL showing insulin resistance. Thirty-two patients with unexplained RPL were included in this study. Following the diagnosis of a miscarriage, the decidua and villi of the patient were surgically collected. Fasting blood glucose and insulin levels were measured, and HOMA-β was calculated. Using IHC and ELISA, the expression of IGFBP-1, PRL and PROK1 in the decidua and IGF-2 in the villi were analyzed in patients with euploid miscarriage with a high HOMA-β index (n = 8) and compared to controls (euploid miscarriage with normal HOMA-β: n = 12, aneuploid miscarriage with normal HOMA-β: n = 12). The co-localization of PROK1 and IGFBP-1 was observed in the decidua by IHC. In the decidua of RPL patients with high HOMA-β, the expression levels of IGFBP-1 and PRL were significantly lower, whereas the PROK1/IGFBP-1 ratio was significantly higher compared to that of the controls. IGF-2 expression in villi was significantly lower in RPL patients with high HOMA-β. Impaired decidualization and excessive PROK1 production may have pathological implications in patients with unexplained RPL with insulin resistance, especially under the state of hyper insulin production.

Diagnostic workup of endocrine dysfunction in recurrent pregnancy loss: a cross-sectional study in Northeast China.

To evaluate the prevalence of abnormal endocrine dysfunction for recurrent pregnancy loss (RPL) amongst patients with two versus three or more pregnancy losses. This cross-sectional study retrospectively collected pre-pregnancy data of 537 women diagnosed with RPL in Shengjing Hospital of China Medical University from 2017 to 2022, including the baseline data of patients and the test results of endocrine factors. Several endocrine dysfunction included in this study were: thyroid dysfunction, obesity, hyperprolactinemia, polycystic ovary syndrome and blood glucose abnormality. Furthermore, vitamin D level were collected to study its relationship with endocrine dysfunction. Finally, we subdivided the patients according to the number of previous pregnancy loss and compared the prevalence of endocrine dysfunction between subgroups. Among 537 RPL patients, 278 (51.8%) patients had abnormal endocrine test results. The highest incidence of endocrine dysfunction was thyroid dysfunction (24.39%, 131/537), followed by hyperprolactinemia (17.34%, 85/490), obesity (10.8%, 58/537), polycystic ovary syndrome (10.50%, 56/533), and abnormal blood glucose (5.29%, 27/510). Only 2.47%(13/527) of patients have vitamin D level that reach the standard. After subdividing the population according to the number of pregnancy loss, we did not find that the incidence of endocrine dysfunction (P=0.813), thyroid dysfunction (P=0.905), hyperprolactinemia (P=0.265), polycystic ovary syndrome (P=0.638), blood glucose abnormality (P=0.616) and vitamin D deficiency (P=0.908) were different among patients with two versus three or more pregnancy losses. However, obesity (P=0.003) was found more frequently observed in patients with more times of pregnancy loss. The prevalence of endocrine dysfunction in RPL population is high. There is no difference in the prevalence of endocrine dysfunction, except for obesity, among patients with two or more pregnancy losses, which may suggest investigations of endocrine dysfunction when patients have two pregnancy losses.

Radiomics optimizing the evaluation of endometrial receptivity for women with unexplained recurrent pregnancy loss.

The optimization of endometrial receptivity (ER) through individualized therapies has been shown to enhance the likelihood of successful gestation. However, current practice lacks comprehensive methods for evaluating the ER of patients with recurrent pregnancy loss (RPL). Radiomics, an emerging AI-based technique that enables the extraction of mineable information from medical images, holds potential to offer a more objective and quantitative approach to ER assessment. This innovative tool may facilitate a deeper understanding of the endometrial environment and enable clinicians to optimize ER evaluation in RPL patients. This study aimed to identify ultrasound radiomics features associated with ER, with the purpose of predicting successful ongoing pregnancies in RPL patients, and to assess the predictive accuracy of these features against regular ER parameters. This retrospective, controlled study involved 262 patients with unexplained RPL and 273 controls with a history of uncomplicated full-term pregnancies. Radiomics features were extracted from ultrasound endometrial segmentation images to derive a radiomics score (rad-score) for each participant. Associations between rad-scores, baseline clinical variables, and sonographic data were evaluated using univariate and multivariate logistic regression analyses to identify potential indicators of RPL. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive accuracy of the rad-score and other identified indicators in discriminating RPL cases. Furthermore, the relationships between age and these identified indicators were assessed via Pearson correlation analysis. From the 1312 extracted radiomics features, five non-zero coefficient radiomics signatures were identified as significantly associated with RPL, forming the basis of the rad-score. Following multivariate logistic regression analysis, age, spiral artery pulsatility index (SA-PI), vascularisation index (VI), and rad-score emerged as independent correlates of RPL (all P<0.05). ROC curve analyses revealed the superior discriminative capability of the rad-score (AUC=0.882) over age (AUC=0.778), SA-PI (AUC=0.771), and VI (AUC=0.595). There were notable correlations between age and rad-score (r=0.275), VI (r=-0.224), and SA-PI (r=0.211), indicating age-related variations in RPL predictors. This study revealed a significant association between unexplained RPL and elevated endometrial rad-scores during the WOI. Furthermore, it demonstrated the potential of rad-scores as a promising predictive tool for successful ongoing pregnancies in RPL patients.