ESHRE guideline: recurrent pregnancy loss

Unveiling the molecular mechanisms of recurrent miscarriage through endoplasmic reticulum stress related gene expression

Recurrent miscarriage (RM) is a reproductive disorder affecting couples worldwide. The underlying molecular mechanisms remain elusive, even though emerging evidence has implicated endoplasmic reticulum stress (ERS). We investigated RM- and ERS-related genes to develop a diagnostic model that can enhance predictive ability. We utilized the R package GEO query to extract and process Gene Expression Omnibus data, applying batch correction, normalization, and differential gene expression analysis with limma. ERS-related differentially expressed genes (ERSRGs) were identified through Gene Ontology and Kyoto Encyclopedia of genes and genomes analyses, and their diagnostic potential was assessed. Diagnostic models were developed using logistic regression, support vector machines, and least absolute shrinkage and selection operators, complemented by immune infiltration analysis and regulatory network construction. Integrated analysis revealed 1395 differentially expressed genes (DEGs), including 626 upregulated and 769 downregulated genes. Seventeen ERSRGs were identified. KEAP1 and YIPF5 displayed high diagnostic accuracy (area under the curve [AUC] > 0.9). Gene Ontology and Kyoto Encyclopedia of genes and genomes analyses highlighted the role of ESRDEGs in cellular responses to ERS, protein processing, and apoptosis. Diagnostic models demonstrated robust predictive performance (AUC > 0.9). A molecular interaction was found between RM and the ERS response, and the identified ESRDEGs could serve as potential biomarkers for diagnosis.

Reproductive Outcomes After Hysteroscopic Adhesiolysis in Patients Experiencing Recurrent Pregnancy Loss and Intrauterine Adhesions

OBJECTIVE

This study aims to evaluate the reproductive outcomes after hysteroscopic adhesiolysis in patients experiencing recurrent pregnancy loss (RPL) combined with intrauterine adhesions (IUA).

DESIGN

Single-center retrospective cohort study.

SETTING

International referral hospital for women with IUA and RPL.

PATIENTS

Between January 2018 and June 2022, a cohort of 64 women diagnosed with RPL and IUA were studied, with a follow-up period of at least one year after hysteroscopic adhesiolysis.

INTERVENTIONS

All patients had a diagnosis of IUA from the diagnostic hysteroscopy and were treated with hysteroscopic adhesiolysis, utilizing intraoperative ultrasound monitoring as required.

MAIN MEASUREMENTS

Live birth rate and menstrual pattern change (subjective assessment) after hysteroscopic adhesiolysis.

RESULTS

In our cohort, 59.38% (38/64) achieved pregnancy following hysteroscopic adhesiolysis, with 92.11% (35/38) conceiving within two years of the procedure. The miscarriage rate was recorded at 17.19% (11/64), and the live birth rate stood at 42.19% (27/64). Throughout the extended follow-up period, 64.06% (41/64) of the patients reported increased menstrual blood volume and improvements in menstrual patterns posthysteroscopic adhesiolysis. Univariate analysis indicated that being aged ≥35 years (p = .026), having a history of infertility (p = .003), the presence of moderate or severe IUA (p = .023), and experiencing menstrual improvements postsurgery (p = .001) were independent predictors of live birth. Multivariate analysis further identified that women with a history of infertility had a reduced chance of live birth following hysteroscopic adhesiolysis (p = .008), while those who reported menstrual pattern improvements postoperatively had an increased probability of achieving a live birth (p = .031).

CONCLUSIONS

Our findings indicate that RPL and IUA patients without prior infertility and showing menstrual pattern improvement after hysteroscopic adhesiolysis, are more likely to achieve live births. Standardized hysteroscopic treatment, postoperative anti-adhesion care, and early pregnancy planning are key to improving fertility outcomes in these patients.

Vitamin B12 is correlated with insulin resistance and metabolism disorder markers in women with recurrent pregnancy loss

OBJECTIVES

Recurrent pregnancy loss (RPL) seriously affects women's reproductive and mental health, and the incidence has increased in recent years. Insulin resistance (IR) acts as a significant contributing factor to RPL. Studies suggest that vitamin B12, folate intake, and homocysteine are correlated with IR, but the exact nature remains controversial and requires further investigation. In this study, we aimed to assess the levels and correlations between vitamin B12-folate-homocysteine and insulin resistance in RPL patients.

STUDY DESIGN

73 control subjects and 256 RPL patients (144 RPL patients without IR and 112 RPL patients with IR) were included in this observational retrospective cross-sectional study. The differences in vitamin B12, folate, and homocysteine levels between RPL patients with and without IR were analyzed using a Student's t-test. Pearson correlations were utilized to examine the correlation between vitamin B12-folate-homocysteine and glucose and lipid metabolism parameters. Multivariable linear regressions were used to assess the independent correlation of each factor with HOMA-IR.

RESULTS

Compared to the control subjects, RPL patients exhibited lower vitamin B12 (p < 0.001) and folate (p < 0.001), and higher homocysteine (p = 0.001). RPL patients with IR described decreases in vitamin B12 (p = 0.003) and folate (p = 0.028), and increases in homocysteine (p = 0.033) as RPL patients without IR. Vitamin B12 in RPL patients was significantly negatively correlated with homocysteine (r = -0.348, p < 0.001), HOMA-IR (r = -0.214, p < 0.001), BMI (r = -0.160, p = 0.017), TG (r = -0.148, p = 0.039) and CHO (r = -0.149, p = 0.038) and positively correlated with folate (r = 0.217, p < 0.001). In multivariable linear regressions, after adjusting for age, strong correlations were observed between vitamin B12 (β = -0.197, p = 0.010), BMI (β = 0.466, p < 0.001), and HOMA-IR in RPL patients.

CONCLUSION

Vitamin B12 is significantly correlated with IR in RPL patients. Circulating vitamin B12-folate-homocysteine metabolism could be a window of the pathological process of IR, obesity, and lipid metabolism disorders in RPL patients.

Etiology and diagnostic approach of recurrent miscarriage at a reference center in Bucaramanga, Colombia

OBJECTIVE

The purpose of this study was to determine the etiologies of recurrent miscarriage in our hospital and whether its diagnostic approach followed the recommendations of the American Society of Reproductive Medicine (ASRM) guidelines published in 2012 and the National Institute for Health and Care Excellence (NICE) guidelines published in 2011.

METHODS

This was a retrospective study. The medical records of 158 patients diagnosed with recurrent miscarriage between 2013 and 2018 at Santander University Hospital were reviewed. The Institutional Review Board of HUS approved the study in May 2020.

RESULTS

The most common etiologies identified were protein S deficiency, thrombophilia, and cervical insufficiency, with incidence rates of 25.9%, 10.7%, and 3.8%, respectively. Moreover, the most frequently requested diagnostic tests were for protein S, protein C, and anti-phospholipid IgG. Abnormal results for protein S were obtained in 49% of the patients, whereas lupus anticoagulant was abnormal in 12.8%, and Factor V Leiden gene mutations in 8.5% of the patients. Three substantial deviations from the recommended diagnostic approach for recurrent miscarriage by international guidelines were identified in our population: the lack of request for cytogenetic analysis of pregnancy tissue, request for cytogenetic analysis for the parents in only 0.6% of the study sample, and the request for imaging tests to assess uterine anatomy in only 6.3% of the studied population. Both the ASRM and NICE guidelines were only partially followed with a combined adherence rate of 66.5%.

CONCLUSION

The diagnostic approach for recurrent miscarriage poses important clinical challenges when compared to the recommendations of international guidelines. Therefore, the development of a local recurrent miscarriage assessment protocol is proposed in our institution.

Recurrent pregnancy loss: a male crucial factor-A systematic review and meta-analysis

BACKGROUND

Recurrent pregnancy loss (RPL), defined as two or more failed clinical pregnancies, affects 1%-3% of couples trying to conceive. Nowadays up to 50% of cases remain idiopathic. In this context, paternal factors evaluation is still very limited. The aim is to address the topic of the male factor in RPL with a broad approach, analyzing collectively data on sperm DNA fragmentation (SDF) and semen parameters. We systematically searched in Pubmed/MEDLINE and Google Scholar from inception to February 2023. A protocol has been registered on PROSPERO (ID number CRD42022278616). PRISMA guidelines were followed.

METHODS

Pooled results from 20 studies revealed a higher DNA fragmentation rate in the RPL group compared to controls (mean difference [MD] 9.21, 95% CI 5.58-12.85, p < 0.00001, I2 98%). Age, body mass index (BMI), smoking, and alcohol intake were not associated with DNA fragmentation. Subgroup analysis by different SDF assays (TUNEL and COMET at a neutral pH vs. indirect assessment with other assays) and ethnicity did not highlight different results (p = 0.25 and 0.44).

RESULTS

Results pooled from 25 studies showed a significant difference comparing RPL and control groups regarding ejaculation volume (MD -0.24, 95% CI -0.43; -0.06, p 0.01, I2 66%), total sperm number (MD -10.03, 95% CI -14.65; -5.41, p < 0.0001, I2 76%), total sperm motility (MD -11.20, 95% CI -16.15; -6.25, p < 0.0001, I2 96%), progressive sperm motility (MD -7.34, 95% CI -10.87; -3.80, p < 0.0001, I2 97%), and normal sperm morphology (MD -5.99, 95% CI -9.08; -2.90, p 0.0001, I2 98%). A sub-analysis revealed that Asian and Africans, but not white-European RPL men had lower progressive sperm motility compared to controls.

CONCLUSION

In conclusion, current review and meta-analysis findings suggested that SDF and some specific semen parameters were associated with RPL in a multi-ethnic evaluation. This effort opens future direction on a growing awareness of, first, how the male factor plays a key role and, second, how appropriate would be to establish a direct dialogue between the gynecologist and the urologist.

PATIENT SUMMARY

We performed a systematic review and meta-analysis on the male component of RPL. We found that sperm DNA fragmentation and some specific sperm parameters are significantly associated with RPL.

Use of oral allylestrenol in women with recurrent spontaneous abortion: A retrospective clinical trial

Recurrent spontaneous abortion (RSA), defined as two or more clinically confirmed pregnancies that end before 20-24 weeks of gestation, encompasses both embryonic and fetal losses and is a significant clinical challenge. The aim of this study was to compare the efficacy of allylestrenol (AT) and progesterone in improving pregnancy outcomes in RSA. From June 2021 to June 2024, 480 participants were randomly assigned to an AT, Progesterone, or Control group. Key outcomes included early pregnancy rates, ongoing pregnancies with fetal heart activity, live birth rates after 24 weeks, and pregnancy loss before 24 weeks. Results indicated significantly higher pregnancy rates at 6-8 weeks in both the Allylestrenol (71.8%) and Progesterone groups (76.2%) compared to the Control group (57.5%). At 12 weeks, ongoing pregnancies with fetal heart activity were higher in the Allylestrenol (65%) and Progesterone groups (64%) versus the Control group (52.5%). Both treatment groups had higher live birth rates (60% and 60.6%) compared to the Control group (45%). Pregnancy loss before 24 weeks was lower in both treatment groups (31.8% and 33.1%) compared to the Control group (38.7%). No significant adverse reactions were observed, indicating good safety profiles for both treatments. These findings suggest that both treatments effectively improve pregnancy outcomes in cases of RSA with satisfactory safety, supporting their potential clinical use. However, further research is needed to explore their long-term effects and broader applicability in clinical settings.

FXYD1 was identified as a hub gene in recurrent miscarriage and involved in decidualization via regulating Na/K-ATPase activity

PURPOSE

Recurrent miscarriage (RM) is a distressing and complicated adverse pregnancy outcome. It is commonly recognized that insufficient decidualization could result in RM, but the molecular mechanisms of decidual impairment are still not fully understood. Thus, this study aimed to identify novel key genes potentially involved in RM and explore their roles played in endometrial decidualization.

METHODS

Initially, a combinative analysis of decidual and mid-secretory endometrial transcriptomes was performed to discover hub genes involved in the etiology of RM. And the expression levels of hub genes were evaluated in both primary decidual stromal cells (DSCs) and decidual tissues. Subsequently, the immortalized human endometrial cell line, T-HESCs, was used to investigate whether FXYD1 overexpression affects decidualization by regulating Na/K-ATPase activity.

RESULTS

FXYD domain containing ion transport regulator 1 (FXYD1) was identified as a hub gene in the pathogenesis of RM through various bioinformatic methods. Abnormally increased FXYD1 expression was observed in DSCs and decidual tissues from RM patients compared to that of the normal group. Furthermore, in vitro decidualization was obviously inhibited by the overexpression of FXYD1. Additionally, Na/K-ATPase activity was significantly elevated during decidualization, whereas overexpression of FXYD1 reduced Na/K-ATPase activity. Bufalin, a Na/K-ATPase inhibitor, showed an effectively inhibitory effect on decidualization.

CONCLUSIONS

Collectively, FXYD1 was discovered as a hub gene associated with RM, and its expression levels in RM patients were significantly upregulated. Increased FXYD1 expression might lead to decidualization defects by reducing Na/K-ATPase activity, of which presented a novel prospective treatment target for RM.

Intraoperative ultrasound for uterine septum resection: a systematic review and meta-analysis

Septate uterus is one of the most common uterine malformations. Recent studies suggest that uterine septa may negatively affect fertility. In cases of recurrent pregnancy loss (RPL) or infertility, hysteroscopic metroplasty has been considered the primary treatment for septate uterus. This systematic review and meta-analysis aims to evaluate whether intraoperative ultrasound monitoring may improve the efficacy of hysteroscopic metroplasty compared to other types of intraoperative monitoring or to unguided resections. An electronic database search was performed to identify articles published until June 15, 2023. Five studies (two randomized clinical trials, two prospective studies and one retrospective cohort study) fulfilled the inclusion criteria. The primary outcome was the rate of residual septum > 10 mm after hysteroscopic metroplasty in the ultrasound (US) monitoring group compared to the rate of residual septum using other types of intraoperative monitoring/no monitoring (control group). The secondary outcomes were any residual septa, surgical time, complications, uterine perforations and reproductive outcomes. Intraoperative ultrasound for uterine septum resection significantly reduced the rate of residual septum > 10 mm and the rate of any residual septa compared to the control group. There was no statistically significant difference in the procedure time between women undergoing intraoperative US monitoring versus the control group. A trend toward reduction of surgical complications was observed in the intraoperative US group compared to the control group. In conclusion, intraoperative ultrasound during metroplasty may reduce the rate of the residual septum with no surgical time differences. Further studies are warranted to understand how this may improve reproductive outcomes.

Association of HLA-G 3'-UTR Haplotypes With Recurrent Spontaneous Abortion in Women From Northwest Iran

BACKGROUND AND OBJECTIVE(S)

Human leukocyte antigen-G (HLA-G) is a critical protein in immune regulation and tolerance. Recurrent spontaneous abortion (RSA) is a complex disease influenced by genetic, immune dysfunction, and environmental factors. This study investigates the role of HLA-G polymorphisms in the development of RSA.

METHODS

Blood samples were collected from 80 women with RSA and 200 women without a history of RSA. After DNA extraction, PCR was used to sequence the 3'-UTR region. Allelic and genotypic frequencies were analyzed, and Haploview software was used for haplotype analysis.

RESULTS

Individual polymorphisms did not significantly differ between the two groups. However, haplotype analysis revealed significant differences. The UTR-2 haplotype was more frequent in the RSA group compared to the healthy control group (p = 0.020), suggesting a potential association. Conversely, the UTR-4 haplotype had a significantly lower frequency in the RSA group (p = 0.041), indicating a protective role against RSA.

CONCLUSIONS

While individual polymorphisms did not differ significantly, haplotype analysis identified significant associations with RSA. These findings provide valuable insights into the genetic basis of the disease and may contribute to the development of new treatments and diagnostic tools.

Classification of idiopathic recurrent spontaneous miscarriage using FTIR and Raman spectroscopic fusion technology

Recurrent spontaneous miscarriage refers to the repeated loss of two or more clinically detected pregnancies occurring within 24 weeks of gestation. No identifiable cause has been identified for nearly 50% of these cases. This group is referred to as idiopathic recurrent spontaneous miscarriage (IRSM) or miscarriage of unknown origin. Due to lack of robust scientific evidence, guidelines on the diagnosis and management of IRSM are not well defined and often contradictory. This motivates us to explore the vibrational fingerprints of endometrial tissue in these women. Endometrial tissues were collected from women undergoing IRSM (n = 20) and controls (n = 20) corresponding to the window of implantation. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectra were obtained within the range of 400-4000 cm-1 using Agilent Cary 630 FTIR spectrometer. Raman spectra were also generated within the spectral window of 400-4000 cm-1 using Thermo Fisher Scientific, DXR Raman spectrophotometer. Based on the limited molecular information provided by a single spectroscopic tool, fusion strategy combining Raman and ATR-FTIR spectroscopic data of IRSM is proposed. The significant features were extracted applying principal component analysis (PCA) and wavelet threshold denoising (WTD) and fused spectral data used as input into support vector machine (SVM), adaptive boosting (AdaBoost) and decision tree (DT) models. Altered molecular vibrations associated with proteins, glutamate, and lipid metabolism were observed in IRSM using Raman spectroscopy. FTIR analysis indicated changes in the molecular vibrations of lipids and proteins, collagen dysregulation and impaired glucose metabolism. Combination of both spectroscopic data using mid-level fusion (MLF: 92% using AdaBoost and DT models) and high-level fusion (HLF: 92% using SVM models) methods showed improved IRSM classification accuracy as compared to individual spectral models. Our results indicate that spectral fusion technology hold promise in enhancing diagnostic accuracy of IRSM in clinical settings. Validation of these findings in a larger patient population is underway.

Exploring the clinical and cellular mechanisms of LncRNA-KCNQ1OT1/miR-29a-3p/SOCS3 molecular axis in cases of unexplained recurrent spontaneous abortion

OBJECTIVE

The objective of this study is to explore the functions and mechanisms of the LncRNA-KCNQ1OT1/miR-29a-3p/SOCS3 molecular pathway in the context of unexplained recurrent spontaneous abortion (URSA).

METHODS

We conducted qRT-PCR to assess the levels of LncRNA-KCNQ1OT1, miR-29a-3p, and SOCS3 in both abortion tissues from women who experienced URSA and healthy early pregnant women. A dual-luciferase assay was employed to investigate whether miR-29a-3p targets SOCS3. Furthermore, RNA IP and RNA Pull-Down assays were employed to confirm the interaction between KCNQ1OT1 and SOCS3 with miR-29a-3p. RNA FISH was used to determine the cellular localization of KCNQ1OT1. Additionally, trophoblast cells (HTR8/SVneo) were cultured and the CCK-8 assay was utilized to assess cell proliferation, while flow cytometry was employed to analyze cell apoptosis.

RESULTS

Compared to abortion tissues obtained from healthy early pregnant individuals, those from women who experienced URSA displayed a notable downregulation of KCNQ1OT1 and SOCS3, accompanied by an upregulation of miR-29a-3p. Suppression of KCNQ1OT1 resulted in the inhibition of cell proliferation and the facilitation of apoptosis in HTR8/SVneo cells. Our findings suggest that KCNQ1OT1 may exert a regulatory influence on SOCS3 through a competitive binding mechanism with miR-29a-3p. Notably, KCNQ1OT1 exhibited expression in both the cytoplasm and nucleus, with a predominant localization in the cytoplasm. Furthermore, we observed a negative regulatory relationship between miR-29a-3p and SOCS3, as the miR-29a-3p mimic group demonstrated significantly reduced cell proliferation and an increased rate of apoptosis when compared to the negative control (NC mimic) group. Additionally, the SOCS3 Vector group exhibited a substantial improvement in proliferation capability and a marked reduction in the apoptosis rate in comparison to the NC Vector group. The miR-29a-3p mimic + SOCS3 Vector group demonstrated a remarkable enhancement in proliferation and a reduction in apoptosis when compared to the miR-29a-3p mimic group.

CONCLUSION

The competitive binding of miR-29a-3p to LncRNA-KCNQ1OT1 appears to result in the elevation of SOCS3 expression, consequently fostering the proliferation of trophoblast cells while concomitantly suppressing apoptosis.

The circRNA Landscape in Recurrent Pregnacy Loss (RPL): A Comparison of Four Reproductive Tissues

Recurrent Pregnancy Loss (RPL), also named Recurrent Spontaneous Abortion (RSA), is a common fertility problem that refers to at least two consecutive pregnancy losses and affects 1-2% of couples all over the world. Despite common causes such as genetic abnormalities, uterine anomalies or hormonal and metabolic disorders, there is still a huge challenge in identifying the causes of about 40-60% of RPL patients. Circular RNAs (circRNAs) are endogenous ncRNAs with a unique closed-loop and single-stranded structure. Accumulated evidence indicates the role of circRNAs in embryonic development and implantation, which may help decipher the mechanisms and causes underlying RSA. Four works were selected in the SRA public repository that used RNAseq analysis in control and RPL samples in four tissues: endometrium, chorionic villus tissue, decidua and decidua immune cells. Two programs were selected for circRNA detection: DCC and CIRI2. A total of 1715 candidate circRNAs were detected after filtering the results. In the differential expression analysis, decidual tissue showed the highest percentage of circRNA with differential expression between cases and controls. CircRNAs originating from genes OGA, FNDC3B, RAB11FIP1, SIPA1L2 and GREB1L showed the highest expression in women suffering from pregnancy losses, in decidual tissue or endometrium. In the GO term enrichment analysis, multiple terms related to embryonic development and immunological response were consistently enriched in villus and decidual tissues. Although some differentially expressed circRNAs were shared between tissues, decidua seems the tissue of choice for analyzing the role of circRNAs in RPL.

Methylation Status at DMRs of C14MC and C19MC in Spermatozoa and Chorionic Villi of Individuals Experiencing Recurrent Spontaneous Abortions

Recurrent spontaneous abortions (RSA) is defined as a loss of two or more consecutive clinically recognized pregnancies before the 20th week of gestation. In RSA, several causative maternal factors are known, but still, 50% of the cases remain unexplained. Evidence suggests that paternal factors are also equally important. Epigenetic phenomenon such as genomic imprinting and regulation of gene expression by miRNAs plays an important role in embryonic and placental development. Two large miRNA clusters, C14MC (Chromosome 14 microRNA cluster) and C19MC (Chromosome 19 microRNA cluster) are imprinted and expressed in the placenta during pregnancy and are known to regulate functionally important processes such as the trophoblast proliferation, adhesion, and migration. Hence, we studied the DNA methylation at the Differentially Methylated Regions (DMRs) of these clusters in spermatozoa and chorionic villi by pyrosequencing. In Spermatozoa, few Cytosine followed by Guanosine (CpG) sites at DMRs of C14MC and C19MC showed significant hypermethylation. In Chorionic villi, CpG sites showed significant hypomethylation in the RSA group as compared to control group. Semen parameters like sperm concentration, sperm motility, morphology, and chromatin compaction were comparable in control and RSA groups. The study suggests aberrant DNA methylation in spermatozoa and chorionic villi at DMRs of both miRNA coding clusters to be associated with RSA.

Alloimmune Causes of Recurrent Pregnancy Loss: Cellular Mechanisms and Overview of Therapeutic Approaches

Recurrent pregnancy loss (RPL) is a complex early pregnancy complication affecting 1-2% of couples and is often linked to immune dysfunction. Aberrations in T and B cell subpopulations, as well as natural killer (NK) cell activity, are particularly influential, with studies showing that abnormal NK cell activation and imbalances in T and B cell subtypes contribute to immune-mediated miscarriage risk. Successful pregnancy requires a tightly regulated balance between pro-inflammatory and anti-inflammatory immune responses. In the early stages, inflammation supports processes such as trophoblast invasion and spiral artery remodeling, but this must be tempered to prevent immune rejection of the fetus. In this review, we explore the underlying immune mechanisms of RPL, focusing on how dysregulated T, B, and NK cell function disrupts maternal tolerance. Specifically, we discuss the essential role of uterine NK cells in the early stages of vascular remodeling in the decidua and regulate the depth of invasion by extravillous trophoblasts. Furthermore, we focus on the delicate Treg dynamics that enable the maintenance of optimal immune homeostasis, where the balance, and not only the quantity of Tregs, is crucial for fostering maternal-fetal tolerance. Other T cell subpopulations, such as Th1, Th2, and Th17 cells, also contribute to immune imbalance, with Th1 and Th17 cells promoting inflammation and potentially harming fetal tolerance, while Th2 cells support immune tolerance. Finally, we show how changes in B cell subpopulations and their functions have been associated with adverse pregnancy outcomes. We further discuss current therapeutic strategies aimed at correcting these immune imbalances, including intravenous immunoglobulin (IVIg), glucocorticoids, and TNF-α inhibitors, examining their efficacy, challenges, and potential side effects. By highlighting both the therapeutic benefits and limitations of these interventions, we aim to offer a balanced perspective on clinical applications for women facing immune-related causes of RPL.

Complex chromosomal rearrangements in female carriers experiencing recurrent pregnancy loss or poor obstetric history and literature review

PURPOSE

Complex chromosomal rearrangements (CCRs) often remain unidentified as they are rarely observed in the general population. Females with CCRs are generally recognized on the identification of an affected child with multiple congenital anomalies (MCA) or having a history of repeated pregnancy loss/bad obstetric history (RPL/BOH). In contrast, males with CCRs are diagnosed primarily due to infertility. This study aimed to carry out a systematic epidemiological analysis of CCRs in one of the largest series from the Indian population. In addition, a review of the literature on female CCR carriers experiencing RPL/BOH has been compiled in an attempt to identify the genomic landscape of breakpoints, commonly involved chromosomes, and the breakpoint regions.

METHODS

A total of 8560 healthy individuals with normal physical and mental well-being and had no history of any obvious genetic disorder at the time of presentation were referred for chromosome analysis in view of RPL/BOH between 1994 and 2024. Of them, 8158 had a normal chromosome complement whereas, 402 (4.7%) showed chromosomal aberrations. CCRs were detected in seven individuals, i.e., one partner in each of seven couples with structural rearrangements, all of whom were females. Comprehensive characterization of CCR was carried out using various molecular cytogenetic techniques.

RESULTS

Seven CCR carriers had a total of 25 pregnancies: 20 leading to miscarriages (80%), one leading to the birth of an abnormal child (4%), two medically terminated pregnancies (8%) due to abnormal antenatal findings, and the remaining two were healthy (8%). A total of 13 different chromosomes with 24 non-recurring breakpoints were identified in these cases. Chromosome (#) 2 showed four breaks (16.7%), followed by #1, #4, #6, and #13 with three breaks each (12.5% each), while one break each (4.2% each) was seen on the remaining eight chromosomes (#3, #5, #8, #11, #14, #15, #17, and #21). Type I and type IV CCRs were observed in five (71.4%) and one case (14.3%), respectively, along with a "not a true" CCR (14.3%) in the present study group. Overall, the prevalence of CCRs in couples with RPL/BOH was 0.16%.

CONCLUSIONS

To the best of our knowledge, this is the first study on the epidemiology of CCRs in couples with RPL/BOH of Indian origin. The incidence of CCRs in couples experiencing RPL/BOH in the present cohort was found to be 0.16% with type I CCR being the most predominant of all types, which is congruent with observations from non-Hispanic white and South East Asian populations. The uniqueness and rarity of each CCR pose a challenge in genetic and reproductive counseling.

Potential shared gene signatures and molecular mechanisms between recurrent pregnancy loss and ovarian cancer

Background

Ovarian cancer (OV) is the second most prevalent gynecological tumor. Recurrent pregnancy loss (RPL) refers to two or more spontaneous abortions. However, the molecular mechanisms underlying both OV and RPL remain poorly understood. This article focuses on the exploration of the common genetic characteristics of OV and RPL and their molecular mechanisms.

Methods

The 71 differentially expressed genes associated with RPL and 1427 genes associated with OV survival were analyzed, among which 7 common genes were both important in the pathogenesis of RPL and OV. Then stepAIC analysis was performed to simplify the model and decrease the number of genes, which yielded a final set of 5 prognostic genes with coefficients to construct a prognostic risk scoring system. Univariate and multivariate Cox analyses were conducted to verify the independent prognostic factor for OV patients. GSEA and GO analysis results showed enriched biological pathways in the high/low risk groups, thereby revealing their biological characteristics. The effect of immunotherapy is better in LR patients. There was a significantly higher enrichment score of stemness and higher tumor aneuploidy score in the HR group.

Results

A five-gene prognostic risk model provided a more accurate prognosis for OV, and this prognostic score system was validated using two external cohorts. The risk score was an independent prognostic index for OV patients. Based on levels of ICs, immune cell infiltration, and predicted response, low risk OV patients were more likely to benefit from immunotherapies.

Conclusions

The 5-gene risk model can predict the prognosis of OV patients, which can draw the attention of clinicians and help stratify patients into high and low risk groups for management.

Proposal for a new classification of intrauterine adhesions by sites

The authors propose a new classification of intrauterine adhesions (IUAs) to facilitate understanding for both the gynecologist and the patient, documenting the location and characteristics of the adhesions in a single image. This tool significantly improves surgical planning and patient outcomes in the treatment of intrauterine adhesions. In addition, having a simple and consistent method of describing IUAs will facilitate longitudinal studies tracking the outcomes of various surgical techniques, adhesion barriers and the impact of hormonal treatment. The proposed new classification system may represent a significant advancement in the field of gynecology. Its adoption may facilitate and simplify the representation of intrauterine adhesion sites, allowing for better communication between doctors and more effective management of intrauterine adhesions.

Hypoxia-inducible factors (HIFs) in early pregnancy: implications for miscarriage†

Miscarriage poses a significant threat to both maternal and fetal health. Its etiology remains unknown, and there are no established effective identification or prevention strategies. A low-oxygen environment in early pregnancy is a physiological necessity for embryonic and placental growth. Hypoxia-inducible factors are a family of classic hypoxia signaling molecules whose expression level may fluctuate abnormally because of an imbalance in oxygen levels. Its unusual fluctuations initiate multiple signaling pathways at the maternal womb. Hypoxia-inducible factors are a family of classic hypoxia-signaling molecules and immune tolerance. Notably, aberrant regulation of these processes may lead to miscarriage. This review aims to clarify how the hypoxia-inducible factor-1α mediates the aberrant regulation of biological processes, including autophagy, metabolic reprogramming, et al., and how these effects impact trophoblasts and other cells at the maternal-fetal interface. These findings provide new insights into potential therapeutic and preventive strategies for miscarriage.

Insight into the post-translational modifications in pregnancy and related complications

Successful pregnancy is dependent on a number of essential events, including embryo implantation, decidualization and placentation. Failure of the above process may lead to pregnancy-related complications, including preeclampsia (PE), gestational diabetes mellitus (GDM), preterm birth, fetal growth restriction (FGR), etc., may affect 15% of pregnancies, and lead to increased mortality and morbidity of pregnant women and perinatal infants, as well as the occurrence of short-term and long-term diseases. These complications have distinct etiology and pathogenesis, and the present comprehension is still lacking. Post-translational modifications (PTMs) are important events in epigenetics, altering the properties of proteins through protein hydrolysis or the addition of modification groups to one or more amino acids, with different modification states regulating subcellular localization, protein degradation, protein-protein interaction, signal transduction and gene transcription. In this review, we focus on the impact of various PTMs on the progress of embryo and placenta development and pregnancy-related complications, which will provide important experimental bases for exploring new insights into the physiology of pregnancy and pathogenesis associated with pregnancy complications.

The effect of hereditary thrombophilia on recurrent pregnancy loss: a retrospective cohort study

OBJECTIVE

Thrombophilia screening has been performed in patients with conditions such as previous fetal death, (fetal growth restriction) FGR, preeclampsia, (hemolysis. elevated liver enzyme, low platelet count) HELLP Syndrome, previous abruptio placentae, previous thrombosis in pregnancy, and abnormal placental histology. The actual role of hereditary thrombophilia in recurrent pregnancy loss (RPL) is still debated. This study was intended to determine the incidence of specific gene defects for hereditary thrombophilia and to ascertain their impact on RPL in central Anatolia in Turkey.

METHODS

This retrospective cohort study was performed between January 2012 and December 2022. All pregnant women with a complete hereditary screening profile were included. The investigated gene polymorphisms were methylenetetrahydrofolate reductase (MTHFR) C677T, MTHFR A1298C, Factor V Leiden G1691A, and Factor II prothrombin G20210A. Cases of pregnant women at least two or more consecutive pregnancy losses before 22 weeks of gestation were defined as RPL. The rates of genetic screening and their association with RPL were analyzed.

RESULTS

RPL was identified in 224 (27.58%) of the 812 pregnant women with complete genetic screening. Although there was no difference in terms of age, body mass index, numbers of ectopic pregnancies, molar pregnancies, or dilatation & curettage (p > 0.05), gravity (2.0 [2.0-3.0] vs. 4.0 [3.0-5.0]), parity (1.0 [1.0-2.0] vs. 1.0 [0-1.0]), live birth (1.0 [1.0-2.0] vs. 1.0 [0-1.0]), anembryonic pregnancy (0 [0-0] vs. 0 [0-0]), miscarriage (0 [0-1.0] vs. 3.0 [2.0-3.0]), and stillbirth (0 [0-0] vs. 0 [0-0]) numbers differed significantly between the groups (p < 0.05). While no significant differences were determined in MTHFR A1298C, Factor V Leiden, factor II prothrombin G20210A, or homocysteine levels (p > 0.05), the homozygous MTHFR C677T positivity rates differed significantly (6.3% in the non-RPL group vs. 11.6% in the RPL group, p = 0.027) .

CONCLUSION

The homozygous MTHFR C677T polymorphisms was found to be more frequent in women with RPL. Further studies with larger cohorts are needed to confirm our results.

IL-17 Producing T to Foxp3+CD4+ Regulatory T Cell Ratio as a Diagnostic and Prognostic Marker in Women With Recurrent Pregnancy Loss and Its Implications for Intravenous Immunoglobulin Therapy

PROBLEM

The imbalance in the Th17/Regulatory T (Treg) cell ratio is associated with recurrent pregnancy loss (RPL). This study aimed to determine a cut-off for the Th17/Treg cell ratio to predict pregnancy outcomes in RPL and evaluate the effectiveness of intravenous immunoglobulin (IVIG) based on this cut-off value.

METHOD OF STUDY

This retrospective cohort study included 49 idiopathic RPL and 75 controls. The subgroups of IL-17+ T cell to Foxp3+ T cell ratios in peripheral blood were measured using flow cytometry. The cut-off values of Th17/Treg cell ratios were determined by the ROC curve to distinguish between RPL and controls. The IVIG treatment effectiveness in pregnancy outcome was compared between high- and low-ratio groups. Pearson correlation assessed the Th17/Treg cell ratio's relationship with NK cell cytotoxicity (NKC), NK cell percentage, and Th1/Th2 cell ratio.

RESULTS

Using the ROC curve, we identified six Th17/Treg cell ratio markers with diagnostic value, and the following two, CD3+IL-17+ T cell/CD3+Foxp3high T cell ratio (sensitivity at 97%) and CD4+IL-17+ T cell/CD3+Foxp3high T cell ratio (specificity at 93.61%), showed the highest statistical significance in diagnosing idiopathic RPL. Among the six diagnostic markers, in terms of predicting pregnancy outcomes with IVIG treatment, CD3+IL-17+ T cell/CD4+Foxp3+ T cell ratio was the most valuable prognostic marker. In RPL women with high CD3+IL-17+ T cell/CD4+Foxp3+ T cell ratio (≥ 1.096), the live birth rate (LBR) was improved with IVIG treatment. (IVIG treatment, 78.57% vs. no IVIG, 28.57%, p = 0.026). On the other hand, RPL women with low CD3+IL-17+ T cell/CD4+Foxp3+ T cell ratio did not demonstrate the effectiveness of IVIG (LBRs with IVIG treatment, 50.00% vs. no IVIG, 84.62%, p = 0.219). In a correlation study, the CD3+IL-17+ T cell/CD4+Foxp3+ T cell ratio was an independent prognostic marker, showing no correlation with NKC, NK cell percentage, and Th1/Th2 cell ratio.

CONCLUSION

The CD3+IL-17+ T/CD4+Foxp3+ T cell ratio may serve as a valuable marker for understanding the pathogenesis of RPL, predicting pregnancy outcomes, and selecting candidates for immunotherapy. Our study demonstrates that IVIG treatment can significantly improve LBR in women with a high CD3+IL-17+ T/CD4+Foxp3+ T ratio, offering a promising therapeutic approach for this challenging condition.

Recurrent Pregnancy Loss: Immunological aetiologies and associations with mental health

Recurrent pregnancy loss (RPL) is an obstetric condition estimated to affect 2-4% of childbearing individuals globally. Due to its varied nature, medical societies globally differ in their diagnostic criteria. Its aetiologies are numerous, ranging from anatomic abnormalities to endocrine and immunological factors. Autoimmune factors can attribute to approximately 20% of cases and include dysregulation of immune cells, cytokine production and antiphospholipid syndrome. Treatment pathways vary by aetiology; however, many cases remain unexplained, adding an additional level of complexity to this condition. Due to its recurrent nature, this type of pregnancy loss has profound impacts on mental health during subsequent pregnancies. While some aspects of RPL have been widely investigated, there continues to be a gap in research, such as its impacts on non-birthing parents and specific sociodemographic groups.

Altered Expression of Circulating miR-223-3p in Patients with Idiopathic Recurrent Pregnancy Loss: A Case and Control Study

BACKGROUND

Circulating microRNAs (miRNAs or miRs) are key regulators of a wide array of biological processes that aberrantly express under physiological as well as pathological conditions. This study aims to determine whether altered expression of circulating miR-223-3p in plasma is associated with an increased risk of idiopathic recurrent pregnancy loss (iRPL), and if it could be a novel non-invasive biomarker for diagnosis of iRPL.

MATERIALS AND METHODS

In this case and control study, Plasma samples were obtained from 60 women with a history of ≥ 2 consecutive miscarriages and 60 women with at least one full-term pregnancy and no history of miscarriage. The samples were used to assess the expression of circulating miR-223-3p by quantitative real-time polymerase chain reaction (qPCR) and determine the correlation between patient clinico-demographic parameters and miR-223-3p expression levels. We used receiver operating characteristic (ROC) curve analysis to evaluate the diagnostic accuracy of miR-223-3p for the diagnosis of iRPL.

RESULTS

There was significant up-regulation in miR-223-3p expression in patients with iRPL compared with healthy controls (P=0.002). No significant correlation was found between the expression level of miR-223-3p and the number of miscarriages in iRPL patients (P=0.344). ROC curve analysis revealed that the area under the curve (AUC) value for miR-223-3p was 0.658 [95% confidence interval (95% CI): 0.5590.757, P=0.002).

CONCLUSION

These results suggest that a higher expression level of circulating miR-223-3p may be closely related with the increased risk of iRPL and possibly serve as a promising non-invasive diagnostic biomarker for iRPL.

Pharmacological and toxicological characteristics of baicalin in preventing spontaneous abortion and recurrent pregnancy loss: A multi-level critical review

Relevance

Spontaneous abortion (SAB) and recurrent pregnancy loss (RPL) occur alone or concurrently with increasing incidences recently. Scutellaria baicalensis Georgi (SBG) has been used to prevent pregnancy loss for thousands of years, which is recognized as a "pregnancy-stabilizing herb" in ancient China. Baicalin (BA) and its metabolite baicalein (BE) are the main bioactive flavonoids in the root of SBG.

Methods

In this study, we focused particularly on the metabolism, toxicology, and pharmacological effects of BA at the maternal-fetal interface based on the biological process prediction by network pharmacology. Focused on the systematic review of BA's regulatory mechanisms of immune homeostasis, cell proliferation and invasion, programmed cell death, inflammatory microenvironment, angiogenesis, oxidative stress and vascular remodeling at the maternal-fetal interface, it was found that BA exerts its biological effects to treat SAB and RPL through multiple perspectives and targets. We also critically elucidated the limitations of using BA from a clinical perspective.

Results

We explored the bioavailability, targeting and efficacy of BA from a new perspective (optimization of the BA delivery system, organoid studies based on BA, potential effects of BA on uterine flora and bioactive components). Finally, we propose a multimodal stereo sequencing study of biologically active components based on pathological dynamics incorporating single-cell RNA sequencing, spatially resolved transcriptomics, and single-cell multimodal omics to delve deeper into the fetal-preserving mechanism of BA and to promote the application of BA in clinical practice.

Abnormal miR-122-5p expression in decidual NK cells and its impact on trophoblast behavior: insights into unexplained recurrent pregnancy loss

In the early stages of pregnancy, the maternal-fetal interface is enriched with natural killer (NK) cells that release growth factors to support fetal development and promote the remodeling of uterine spiral arteries. Previous studies have shown that the aberrant frequency and activity of decidual natural killer (dNK) cells are associated with recurrent pregnancy loss (RPL). Various factors regulate the roles of dNK cells and their interactions with trophoblasts to facilitate the colonization and maturation of semiallogeneic embryos. However, knowing precise molecular mechanisms involved in this requires further investigation. Earlier studies revealed that microRNAs (miRNAs) play a significant role in regulating the functions of decidual stromal and trophoblast cells. Although there are few studies on the intervention of malfunctioning dNK cells, this strategy shows promise in regulating abnormal miRNA production in NK cells. This study confirmed miR-122-5p downregulation in dNK cells from patients experiencing unexplained RPL. miR-122-5p regulates apoptosis, inflammatory factor secretion, and cytotoxicity of NK cells. miR-122-5p may contribute to immune tolerance at the maternal-fetal interface by targeting transcription factor T-bet. This study provides a deeper understanding of the mechanisms by which miR-122-5p regulates the function of dNK cells and trophoblasts at the maternal-fetal interface to ensure successful pregnancy.

Altered Expressions of IL-15, IFNG, and HPRT1 Genes in the Thin Endometria of Patients with Reproductive Disorders: A Prospective Comparative Study

Reproductive disorders are common events in modern reproductive medicine, occurring both in spontaneous and assisted pregnancies. Studies on the molecular mechanisms of implantation disorders in thin endometria, including the study of gene transcriptional activities, have shed light on the identification of the potential biological markers of endometrial receptivity. Background/Objectives: The goal of this study was to reveal the significantly dysregulated selected gene expressions between RIF and RPL patients with thin endometria. Methods: Endometrial samples were collected from RIF patients (n = 20) and RPL patients (n = 19) during the implantation window days (LH + 7-LH + 10) of their natural menstrual cycles. Ten genes were chosen as the target genes regarding their possible relations with the implantation process. The total RNA was purified and reverse-transcribed, and gene expressions were quantified by RT-PCR. Results: The expressions of the IL-15, INFG, and HPRT1 genes were significantly decreased in the RIF patients with thin endometria compared to the RPL patients (log2 fold change = 0.92, p = 0.023 for IL-15; log2 fold change = 1.24, p = 0.046 for INFG; and log2 fold change = 0.579, p = 0.046 for HPRT1). There were no significant differences in the expressions of the CXCL8, CXCL1, MMP10, C4BPA, TNC, VEGFB, and HAND2 genes between the groups. Conclusions: Decreased expressions of the IL-15, INFG, and HPRT1 genes were found in patients with RIF with thin endometria compared to the endometria of women with RPL. This has practical significance for clinicians for the differentiated prescription of immunomodulatory therapy in patients undergoing ART programs.

A nomogram and risk stratification to predict subsequent pregnancy loss in patients with recurrent pregnancy loss

STUDY QUESTION

Could the risk of subsequent pregnancy loss be predicted based on the risk factors of recurrent pregnancy loss (RPL) patients?

SUMMARY ANSWER

A nomogram, constructed from independent risk factors identified through multivariate logistic regression, serves as a reliable tool for predicting the likelihood of subsequent pregnancy loss in RPL patients.

WHAT IS KNOWN ALREADY

Approximately 1-3% of fertile couples experience RPL, with over half lacking a clear etiological factor. Assessing the subsequent pregnancy loss rate in RPL patients and identifying high-risk groups for early intervention is essential for pregnancy counseling. Previous prediction models have mainly focused on unexplained RPL, incorporating baseline characteristics such as age and the number of previous pregnancy losses, with limited inclusion of laboratory and ultrasound indicators.

STUDY DESIGN, SIZE, DURATION

The retrospective study involved 3387 RPL patients who initially sought treatment at the Reproductive Immunology Clinic of Renji Hospital, Shanghai Jiao Tong University School of Medicine, between 1 January 2020 and 31 December 2022. Of these, 1153 RPL patients met the inclusion criteria and were included in the analysis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

RPL was defined as two or more pregnancy losses (including biochemical pregnancy loss) with the same partner before 28 weeks of gestation. Data encompassing basic demographics, laboratory indicators (autoantibodies, peripheral immunity coagulation, and endocrine factors), uterine and endometrial ultrasound results, and subsequent pregnancy outcomes were collected from enrolled patients through initial questionnaires, post-pregnancy visits fortnightly, medical data retrieval, and telephone follow-up for lost patients. R software was utilized for data cleaning, dividing the data into a training cohort (n = 808) and a validation cohort (n = 345) in a 7:3 ratio according to pregnancy success and pregnancy loss. Independent predictors were identified through multivariate logistic regression. A nomogram was developed, evaluated by 10-fold cross-validation, and compared with the model incorporating solely age and the number of previous pregnancy losses. The constructed nomogram was evaluated using the AUC, calibration curve, decision curve analysis (DCA), and clinical impact curve analysis (CICA). Patients were then categorized into low- and high-risk subgroups.

MAIN RESULTS AND THE ROLE OF CHANCE

We included age, number of previous pregnancy losses, lupus anticoagulant, anticardiolipin IgM, anti-phosphatidylserine/prothrombin complex IgM, anti-double-stranded DNA antibody, arachidonic acid-induced platelet aggregation, thrombin time and the sum of bilateral uterine artery systolic/diastolic ratios in the nomogram. The AUCs of the nomogram were 0.808 (95% CI: 0.770-0.846) in the training cohort and 0.731 (95% CI: 0.660-0.802) in the validation cohort, respectively. The 10-fold cross-validated AUC ranged from 0.714 to 0.925, with a mean AUC of 0.795 (95% CI: 0.750-0.839). The AUC of the nomogram was superior compared to the model incorporating solely age and the number of previous pregnancy losses. Calibration curves, DCAs, and CICAs showed good concordance and clinical applicability. Significant differences in pregnancy loss rates were observed between the low- and high-risk groups (P < 0.001).

LIMITATIONS, REASONS FOR CAUTION

This study was retrospective and focused on patients from a single reproductive immunology clinic, lacking external validation data. The potential impact of embryonic chromosomal abnormalities on pregnancy loss could not be excluded, and the administration of medication to all cases impacted the investigation of risk factors for pregnancy loss and the model's predictive efficacy.

WIDER IMPLICATIONS OF THE FINDINGS

This study signifies a pioneering effort in developing and validating a risk prediction nomogram for subsequent pregnancy loss in RPL patients to effectively stratify their risk. We have integrated the nomogram into an online web tool for clinical applications.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the National Natural Science Foundation of China (82071725). All authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

N/A.

Shared diagnostic genes and potential mechanisms between polycystic ovary syndrome and recurrent miscarriage revealed by integrated transcriptomics analysis and machine learning

Objective

More and more studies have found that polycystic ovary syndrome (PCOS) is significantly associated with recurrent spontaneous abortion (RSA), but the specific mechanism is not yet clear.

Methods

Based on the GEO database, we downloaded the PCOS (GSE10946, GSE6798 and GSE137684) and RSA (GSE165004, GSE26787 and GSE22490) datasets and performed differential analysis, weighted gene co-expression network (WGCNA), functional enrichment, and machine learning, respectively, on the datasets of the two diseases, Nomogram and integrated bioinformatics analysis such as immune infiltration analysis. Finally, the reliability of the diagnostic gene was verified by external verification and collection of human specimens.

Results

In this study, PCOS and RSA datasets were obtained from Gene Expression Omnibus (GEO) database, and a total of 23 shared genes were obtained by differential analysis and WGCNA analysis. GO results showed that the shared genes were mainly enriched in the functions of lipid catabolism and cell cycle transition (G1/S). DO enrichment revealed that shared genes are mainly involved in ovarian diseases, lipid metabolism disorders and psychological disorders. KEGG analysis showed significant enrichment of Regulation of lipolysis in adipocytes, Prolactin signaling pathway, FoxO signaling pathway, Hippo signaling pathway and other pathways. A diagnostic gene FAM166 B was obtained by machine learning and Nomogram screening, which mainly played an important role in Cellular component. GSEA analysis revealed that FAM166B may be involved in the development of PCOS and RSA by regulating the cell cycle, amino acid metabolism, lipid metabolism, and carbohydrate metabolism. CIBERSORT analysis showed that the high expression of FAM166 B was closely related to the imbalance of multiple immune cells. Further verification by qPCR suggested that FAM166 B could be used as a common marker of PCOS and RSA.

Conclusions

In summary, this study identified FAM166B as a common biomarker for PCOS and RSA, and conducted in-depth research and analysis of this gene, providing new data for basic experimental research and early prognosis, diagnosis and treatment of clinical diseases.

Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) gene polymorphisms and five related serum molecular levels in 2587 patients: Associated differentially with adverse pregnancy

BACKGROUND

The aim of the study is to investigate the relationship between Methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR) polymorphisms, 5 serum related molecular levels and the risk of adverse pregnancies in different genders.

METHODS

Patients aged from 22 to 38 with a history of adverse pregnancy treated in our genetic eugenics clinic of Henan Provincial People's Hospital are selected. The controls aged from 20 to 34 undergoing eugenics examinations in our genetic eugenics clinic that had no history of adverse pregnancy and at least one healthy child are selected. Sanger sequencing and Chemiluminescence Microparticle Immuno Assay (CMIA) are used for detecting the mutations of MTHFR and MTRR and the 5 serum molecular serum levels.

RESULTS

In the female group, MTHFR 677 C > T is associated with Recurrent spontaneous abortion (RSA) (P = 0.0017), Chromosomal abnormality (CA) (P = 0.0053), Cleft lip and palate (CLP) (P = 0.0326) and Brain dysplasia (BD) (P = 0.0072); MTHFR 1298 A > C is associated with Infertility (P = 0.0026) and BD (P = 0.0382); MTRR 66 A > G is associated with CLP (P = 0.0131). In the male group, MTHFR 677 C > T is associated with RSA (P = 0.0003), Infertility (P = 0.0013), CA (P = 0.0027) and BD (P = 0.0293). In the female group, the genotype of MTHFR 677 C > T is associated with RSA (P = 0.0017), CA (P = 0.0014) and BD (P = 0.0021); MTHFR 1298 A > C is associated with Infertility (P = 0.0081) and MTRR 66 A > G is associated with Infertility (P = 0.0309). In the male group, the genotype of MTHFR 677 C > T is associated with RSA (P = 0.0008), Infertility (P = 0.0096) and CA (P = 0.0165) and MTRR 66 A > G is associated with Infertility (P = 0.0158) and congenital heart disease (CHD) (P = 0.0218). In the male group, there is statistically significant difference of the serum Homocysteine (Hcy) levels (P < 0.0001) between adverse pregnancy group and controls. In the female group, there is statistically significant difference of the serum vitamin D levels (P = 0.0015) between adverse pregnancy group and controls.

CONCLUSIONS

Polymorphic variants in MTHFR and MTRR, serum Folic acid (FA), Hcy and B12 levels in the male group and vitamin D levels in the female group are associated differentially with adverse pregnancy.

Embryo retention and live birth in frozen embryo transfer cycles: a cohort study

OBJECTIVE

To study the effect of embryo retention in the transfer catheter on pregnancy outcomes in frozen embryo transfer (FET) cycles.

DESIGN

Retrospective cohort study.

SETTING

Tertiary-care academic medical center.

PATIENT(S)

This retrospective study involved a total of 39,118 women who underwent FET cycles at a tertiary-care academic medical from January 2016 to December 2022.

INTERVENTION(S)

Women were divided into a control group (n = 38,933) and embryo retention group (n = 185). The women in the embryo retention group had been propensity scores matched with those in the control group at a 1:4 ratio.

MAIN OUTCOME MEASURE(S)

The primary outcome was live birth (LB). The secondary outcomes were biochemical pregnancy, clinical pregnancy (CP), miscarriage, and ectopic pregnancy.

RESULT(S)

The overall incidence of embryo retention in the transfer catheter was 0.47% (185/39,118). The pregnancy outcome in the embryo retention group after propensity score matching (PSM) was comparable to that before PSM, with a reduced likelihood of biochemical pregnancy (odds ratio [OR], 0.83; 95% confidence interval [CI], 0.72-0.95), CP (OR, 0.81; 95% CI, 0.69-0.96), and LB (OR, 0.80; 95% CI, 0.66-0.97). In addition, the birth weight in the embryo retention group was higher compared with the control group. However, no differences were observed in terms of miscarriage, ectopic pregnancy, cesarean delivery, as well as gestational age both before and after PSM.

CONCLUSION(S)

Embryo retention in the transfer catheter decreases the chance of biochemical pregnancy, CP, and LB in FET cycles.

Clinical efficacy and adverse effects of LMWH combined with ASA in the treatment of RSA: A meta-analysis and systematic review

BACKGROUND

The incidence of recurrent spontaneous abortion (RSA) in the clinic shows an increasing trend year by year, and the coagulation status of this group of patients is mostly relatively abnormal. Currently, commonly used drugs in clinical practice include Aspirin (ASA) and low molecular weight heparin (LMWH), but their optimal treatment remains controversial. We aimed to evaluate the clinical efficacy and adverse effects of LMWH combined with ASA in the treatment of RSA.

METHODS

Randomized controlled trials of LMWH combined with ASA for RSA were searched in the databases of PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, Wanfang, VIP, and Chinese Biomedical Literature Service System from the construction of the database to June 2024. Data were analyzed using Review Manager 5.3 and Stata software. Dichotomous variables were analyzed using relative risk (RR) and 95% confidence interval (CI) as their statistics. The included literature was assessed for bias and risk of bias of eligible studies using Cochrane risk of bias tool. The risk of bias was evaluated based on the evaluation criteria recommended by the Cochrane Guidance Manual for Systematic Evaluation.

RESULTS

A total of 32 papers with a total of 3397 patients with RSA were finally included. LMWH combined with ASA treatment significantly improved the live birth rate (RR = 1.31, 95% CI: [1.19, 1.45], P < .00001), the rate of preterm stillbirths (RR = 0.23, 95% CI: [0.13, 0.40], P < .00001), rate of term delivery (RR = 1.55, 95% CI: [1.43, 1.67], P < .00001), rate of miscarriage (RR = 0.42, 95% CI: [0.36, 0.48], P < .00001), incidence of petechiae (RR = 0.44, 95% CI: [0.26, 0.72], P = .001), and incidence of thrombocytopenia (RR = 0.61, 95% CI: [0.39, 0.96], P = .03). In contrast, the incidence of preterm live births (RR = 1.07, 95% CI: [0.90, 1.28], P = .44), adverse reactions (RR = 0.77, 95% CI: [0.59, 1.00], P = .05), gingival bleeding (RR = 1.12, 95% CI: [0.65, 1.93], P = .69), and gastrointestinal reactions (RR = 0.87, 95% CI: [0.64, 1.17], P = .35) were not significant.

CONCLUSION

LMWH combined with ASA treatment might improve pregnancy outcomes and reduces the incidence of adverse events in patients with RSA.

Obstetric and perinatal outcomes of women with a history of recurrent pregnancy loss: a meta-analysis of cohort studies

PURPOSE

To assess the risk of adverse obstetric and perinatal outcomes in subsequent pregnancies among women with a history of recurrent pregnancy loss (RPL).

METHODS

Relevant studies were identified by searching the PubMed, Web of Science, and Embase databases. The pooled effect sizes were reported as odds ratios (OR) with their respective 95% confidence intervals (95% CI), and data analysis was performed using the random effects model.

RESULTS

A total of 26 studies involving 4,730,728 women were included in this meta-analysis. The results reveal a significant increase in the prevalence of placenta accreta cases after RPL compared to women without RPL (pooled OR 4.04; 95% CI 1.16-14.15; 2 studies; I2 = 94%; P = 0.03). However, no elevated risk of aneuploidies (pooled OR 1.69, 95% CI 0.73-3.90; 5 studies; I2 = 48%; P = 0.22) or congenital anomalies (pooled OR 1.12, 95% CI 0.97-1.30; 7 studies; I2 = 13%; P = 0.12) in subsequent pregnancies of women with RPL was observed. Additionally, a moderate increase in the risk of various other obstetric and perinatal outcomes was found. The magnitude of the elevated risk of these adverse outcomes varied depending on the region.

CONCLUSIONS

Women with a history of RPL exhibit a significantly elevated risk of placenta accreta in subsequent pregnancies, along with a moderate increase in the risk of various other adverse obstetric and perinatal outcomes. However, RPL does not signify an increased risk of aneuploidies or congenital anomalies in a consecutive pregnancy.

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.

Genetic landscape of thrombophilia in recurrent miscarriages

The etiology of recurrent miscarriage (RM) is extremely heterogeneous, encompassing genetic, immunological, anatomical, endocrine, thrombophilic, infectious, and uterine abnormalities. Thrombophilia is a major contributor to pregnancy complications, potentially harming the fetus and jeopardizing the continuation of pregnancy. Therefore, successful pregnancy outcomes depend on maintaining a delicate balance between coagulation and fibrinolytic factors, crucial for ensuring the adjustment of the basal plate to facilitate adequate placental perfusion. Despite numerous studies shedding light on the role of thrombophilic factors and genetic variations in RM, the exact pathogenesis remains unclear. It is imperative to systematically rule out thrombophilia and other related factors responsible for pregnancy disorders and RMs to guide appropriate and active management strategies. Addressing thrombophilia continues to present challenges in terms of effective treatment. The current review aims to address the heterogeneity of RM as a therapeutic challenge, emphasizing the need for standardized diagnostic tests and welldesigned multicenter research trials to gather robust, evidence-based data on thrombophilic causes of RM and provide effective treatment. The goal is to enhance the understanding of thrombophilic factors and genetic landscapes associated with RM through various approaches, including candidate gene studies, genome-wide association studies, and high-throughput sequencing. Meta-analyses have underscored the significance of genetic aberrations in RM, highlighting the necessity for identifying critical mutations implicated in the etiopathogenesis of miscarriages to pave the way for implementation of targeted clinical therapies.

From bench to in silico and backwards: What have we done on genetics of recurrent pregnancy loss and implantation failure and where should we go next?

Human reproduction goes through many challenges to its success and in many cases it fails. Cases of pregnancy loss are common outcomes for pregnancies, and implantation failures (IF) are common in assisted reproduction attempts. Although several risk factors have already been linked to adverse outcomes in reproduction, many cases remain without a definitive cause. Genetics of female reproduction is a field that may bring some pieces of this puzzle; however, there are no well-defined genes that might be related to the risk for recurrent pregnancy loss (RPL) and IF. Here, we present a literature review of the studies of genetic association in RPL and IF carried out in the Brazilian population and complemented with a database search to explore genes previously related to RPL and IF, where a search for genes previously involved in these conditions was performed in OMIM, HuGE, and CTD databases. Finally, we present the next steps for reproductive genetics investigation, through genomic sequencing analyses and discuss future plans in the study of RPL genetics. The combined strategy of looking for literature and databases is useful to raise hypotheses and to identify underexplored genes related to RPL and IF.

Optimizing evaluation of endometrial receptivity in recurrent pregnancy loss: a preliminary investigation integrating radiomics from multimodal ultrasound via machine learning

Background

Recurrent pregnancy loss (RPL) frequently links to a prolonged endometrial receptivity (ER) window, leading to the implantation of non-viable embryos. Existing ER assessment methods face challenges in reliability and invasiveness. Radiomics in medical imaging offers a non-invasive solution for ER analysis, but complex, non-linear radiomic-ER relationships in RPL require advanced analysis. Machine learning (ML) provides precision for interpreting these datasets, although research in integrating radiomics with ML for ER evaluation in RPL is limited.

Objective

To develop and validate an ML model that employs radiomic features derived from multimodal transvaginal ultrasound images, focusing on improving ER evaluation in RPL.

Methods

This retrospective, controlled study analyzed data from 346 unexplained RPL patients and 369 controls. The participants were divided into training and testing cohorts for model development and accuracy validation, respectively. Radiomic features derived from grayscale (GS) and shear wave elastography (SWE) images, obtained during the window of implantation, underwent a comprehensive five-step selection process. Five ML classifiers, each trained on either radiomic, clinical, or combined datasets, were trained for RPL risk stratification. The model demonstrating the highest performance in identifying RPL patients was selected for further validation using the testing cohort. The interpretability of this optimal model was augmented by applying Shapley additive explanations (SHAP) analysis.

Results

Analysis of the training cohort (242 RPL, 258 controls) identified nine key radiomic features associated with RPL risk. The extreme gradient boosting (XGBoost) model, combining radiomic and clinical data, demonstrated superior discriminatory ability. This was evidenced by its area under the curve (AUC) score of 0.871, outperforming other ML classifiers. Validation in the testing cohort of 215 subjects (104 RPL, 111 controls) confirmed its accuracy (AUC: 0.844) and consistency. SHAP analysis identified four endometrial SWE features and two GS features, along with clinical variables like age, SAPI, and VI, as key determinants in RPL risk stratification.

Conclusion

Integrating ML with radiomics from multimodal endometrial ultrasound during the WOI effectively identifies RPL patients. The XGBoost model, merging radiomic and clinical data, offers a non-invasive, accurate method for RPL management, significantly enhancing diagnosis and treatment.

Effect of IVIG therapy on pregnant women with unexplained recurrent spontaneous abortion: a systematic review and meta-analysis

Objective

To assess the effect of intravenous immunoglobulin (IVIG) therapy on unexplained recurrent spontaneous abortion (URSA).

Methods

We retrieved all randomized controlled trials (RCTs) related to the effect of IVIG therapy on URSA in the following databases: PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials before April 30, 2023, according to the PRISMA statement. The therapeutic effect of IVIG was measured by live birth rates. Quality assessment was conducted independently by two reviewers, based on the Newcastle-Ottawa scale. For the meta-analysis, we used odds ratios (random effects model and fixed effects model). The between-study heterogeneity was assessed by the Q test. Publication bias was assessed by funnel plots.

Results

A total of 12 studies with 751 participants were included in this meta-analysis. There was no statistical significance [OR = 1.07, 95%CI (0.65, 1.75), P=0.80] between the IVIG group and the non-IVIG group, including low molecular weight heparin (LMWH) plus low-dose aspirin (LDA), intralipid, multivitamins, albumin, and normal saline. A subgroup analysis was conducted according to the different treatment regimens of the non-IVIG group. Compared to the placebo group, including multivitamins, albumin, and saline, the live birth rate of the IVIG group is superior, but there was no statistical significance [OR =1.43, 95%CI (0.99, 2.07), P=0.05]. Another subgroup analysis was performed according to URSA with positive for antiphospholipid antibodies (aPLs). Results showed the live birth rate of IVIG on URSA with positive for aPLs is inferior to that of LMWH plus LDA [OR = 0.25, 95%CI (0.11, 0.55), P=0.0007].

Conclusions

IVIG didn't increase the live birth rate of URSA compared to placebo. Conversely, compared with the IVIG, the LMWH plus LDA treatment schedule can increase the live birth rate of URSA with positive for aPLs.

Smoking and recurrent pregnancy loss: A cohort study of 2829 women

Smoking during pregnancy is associated with negative reproductive outcome. Less is known about the impact of smoking or previous smoking in women with recurrent pregnancy loss (RPL) which this study aimed to investigate. We included all women <42 years (n=2829) referred to a RPL unit at Copenhagen University Hospital between January 2000 and December 2021 in the cohort with follow-up until June 2022. Patients were categorized as 'smokers at time of referral', 'never-smokers' or 'former smokers'. The main outcomes were pregnancy history prior to referral, prospective pregnancy rate, live birth rate, rates of ectopic pregnancy, and stillbirth. At referral, smokers (n=373) were on average 2.0 years younger (P<0.001) and had experienced significantly more pregnancy losses (P<0.001), and stillbirths (P=0.01) compared to never-smokers (n=2100). Former smokers had a higher risk of stillbirth prior to referral compared to never-smokers but no differences in pregnancy rate or other outcomes. Prospective pregnancy rates were lower for smokers compared with never-smokers (71.8% vs. 77.5%, P=0.02). Live birth rate was 58.0% for the 243 women who smoked at referral compared to 61.4% for the 1488 never-smokers (P=0.32). Stillbirth and ectopic pregnancies were significantly more common for smokers (2.8% vs. 0.4%, P=0.01; 6.0% vs. 2.0%, P<0.008). Women with RPL who smoked at referral were referred younger with a higher number of previous pregnancy losses and stillbirths compared with never-smokers. Fewer smokers achieved a pregnancy after referral but those who did had a similar live birth rate compared to never-smokers, although stillbirths and ectopic pregnancies were more common.

Primary cilia abnormalities participate in the occurrence of spontaneous abortion through TGF-β/SMAD2/3 signaling pathway

Spontaneous abortion is the most common complication in early pregnancy, the exact etiology of most cases cannot be determined. Emerging studies suggest that mutations in ciliary genes may be associated with progression of pregnancy loss. However, the involvement of primary cilia on spontaneous abortion and the underlying molecular mechanisms remains poorly understood. We observed the number and length of primary cilia were significantly decreased in decidua of spontaneous abortion in human and lipopolysaccharide (LPS)-induced abortion mice model, accompanied with increased expression of proinflammatory cytokines interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. The length of primary cilia in human endometrial stromal cell (hESC) was significantly shortened after TNF-α treatment. Knocking down intraflagellar transport 88 (IFT88), involved in cilia formation and maintenance, promoted the expression of TNF-α. There was a reverse regulatory relationship between cilia shortening and TNF-α expression. Further research found that shortened cilia impair decidualization in hESC through transforming growth factor (TGF)-β/SMAD2/3 signaling. Primary cilia were impaired in decidua tissue of spontaneous abortion, which might be mainly caused by inflammatory injury. Primary cilia abnormalities resulted in dysregulation of TGF-β/SMAD2/3 signaling transduction and decidualization impairment, which led to spontaneous abortion.

Cell-Free DNA Analysis of Fetal Aneuploidies in Early Pregnancy Loss

Background: Products of conception samples are often collected and analyzed to try to determine the cause of an early pregnancy loss. However, sample collection may not always be possible, and maternal cell contamination and culture failure can affect the analysis. Cell-free DNA-based analysis of a blood sample could be used as an alternative method in early pregnancy loss cases to detect if aneuploidies were present in the fetus. Methods: In this prospective study, blood samples from early pregnancy loss patients were analyzed for the presence of fetal aneuploidies using a modified version of a noninvasive prenatal testing assay for cell-free DNA analysis. Results from cell-free DNA analysis were compared against the gold standard, microarray analysis of products of conception samples. This study was registered with ClinicalTrials.gov, identifier: NCT04935138. Results: Of the 76 patient samples included in the final study cohort, 11 were excluded from performance calculations. The 65 patient samples included in the final analysis included 49 with an abnormal microarray result and 16 with a normal microarray result. Based on results from these 65 samples, the study found that genome-wide cell-free DNA analysis had a sensitivity of 73.5% with a specificity of 100% for the detection of fetal aneuploidies in early pregnancy loss cases. Conclusions: This prospective study provides further support for the utility of cell-free DNA analysis in detecting fetal aneuploidies in early pregnancy loss cases. This approach could allow for a noninvasive method of investigating the etiology of miscarriages to be made available clinically.

KAT8-mediated H4K16ac is essential for sustaining trophoblast self-renewal and proliferation via regulating CDX2

Abnormal trophoblast self-renewal and differentiation during early gestation is the major cause of miscarriage, yet the underlying regulatory mechanisms remain elusive. Here, we show that trophoblast specific deletion of Kat8, a MYST family histone acetyltransferase, leads to extraembryonic ectoderm abnormalities and embryonic lethality. Employing RNA-seq and CUT&Tag analyses on trophoblast stem cells (TSCs), we further discover that KAT8 regulates the transcriptional activation of the trophoblast stemness marker, CDX2, via acetylating H4K16. Remarkably, CDX2 overexpression partially rescues the defects arising from Kat8 knockout. Moreover, increasing H4K16ac via using deacetylase SIRT1 inhibitor, EX527, restores CDX2 levels and promoted placental development. Clinical analysis shows reduced KAT8, CDX2 and H4K16ac expression are associated with recurrent pregnancy loss (RPL). Trophoblast organoids derived from these patients exhibit impaired TSC self-renewal and growth, which are significantly ameliorated with EX527 treatment. These findings suggest the therapeutic potential of targeting the KAT8-H4K16ac-CDX2 axis for mitigating RPL, shedding light on early gestational abnormalities.

Predicting risk of the subsequent early pregnancy loss in women with recurrent pregnancy loss based on preconception data

BACKGROUND

For women who have experienced recurrent pregnancy loss (RPL), it is crucial not only to treat them but also to evaluate the risk of recurrence. The study aimed to develop a risk predictive model to predict the subsequent early pregnancy loss (EPL) in women with RPL based on preconception data.

METHODS

A prospective, dynamic population cohort study was carried out at the Second Hospital of Lanzhou University. From September 2019 to December 2022, a total of 1050 non-pregnant women with RPL were participated. By December 2023, 605 women had subsequent pregnancy outcomes and were randomly divided into training and validation group by 3:1 ratio. In the training group, univariable screening was performed on RPL patients with subsequent EPL outcome. The least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression were utilized to select variables, respectively. Subsequent EPL prediction model was constructed using generalize linear model (GLM), gradient boosting machine (GBM), random forest (RF), and deep learning (DP). The variables selected by LASSO regression and multivariate logistic regression were then established and compared using the best prediction model. The AUC, calibration curve, and decision curve (DCA) were performed to assess the prediction performances of the best model. The best model was validated using the validation group. Finally, a nomogram was established based on the best predictive features.

RESULTS

In the training group, the GBM model achieved the best performance with the highest AUC (0.805). The AUC between the variables screened by the LASSO regression (16-variables) and logistic regression (9-variables) models showed no significant difference (AUC: 0.805 vs. 0.777, P = 0.1498). Meanwhile, the 9-variable model displayed a well discrimination performance in the validation group, with an AUC value of 0.781 (95%CI 0.702, 0.843). The DCA showed the model performed well and was feasible for making beneficial clinical decisions. Calibration curves revealed the goodness of fit between the predicted values by the model and the actual values, the Hosmer-Lemeshow test was 7.427, and P = 0.505.

CONCLUSIONS

Predicting subsequent EPL in RPL patients using the GBM model has important clinical implications. Future prospective studies are needed to verify the clinical applicability.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry with the registration number of ChiCTR2000039414 (27/10/2020).

Recurrent Pregnancy Loss: A Bibliometric Review

Background

The research combined different bibliometric techniques to analyze systematically recurrent pregnancy loss (RPL) documents from 1970 to 2023.

Methods

Overall, 1287 documents from the Web of Science database associated with recurrent pregnancy loss between 1970 and 2023 were identified for more than 300 journals. The data were analyzed with VOSviewer software.

Results

The trend of paying attention to the topic of RPL can be divided into three periods. The number of publications on RPL increased significantly after 2010. Most of the papers were published in Obstetrics and Gynecology and Reproductive Biology areas. Utilizing co-occurrence and co-citation analysis, our study found that the most influential documents mapped the knowledge structure, and projected future research directions. The co-occurrence analysis showed five clusters even though the co-citation analysis designates four.

Conclusion

RPL has increased in recent years exponentially and some areas were explained carefully, therefore these results could be used as a research agenda for the future direction by a range of interested beneficiaries.

Are Altered Expression of Vascular Endothelial Growth Factor and Placental Growth Factor Associated with Placental Angiogenesis in Recurrent Pregnancy Loss?

Angiogenesis is one of the most important steps during pregnancy for placental and fetal development. Based on the hypothesis that vascular insufficiency and altered angiogenesis may lead to early pregnancy loss, the present study was aimed to understand the role of Vascular endothelial growth factor (VEGFA) and Placental growth factor (PLGF) gene expression in placental angiogenesis in the pathogenesis of Recurrent pregnancy loss (RPL). Gene expression analysis of VEGFA and PLGF was carried out in the placental tissue collected from 30 women with recurrent pregnancy loss and compared with the placenta obtained from 16 women with medically terminated pregnancy. The mRNA expression of both VEGFA and PLGF genes were significantly downregulated in the placenta of recurrent pregnancy loss in comparison to the placenta of medically terminated pregnancies. In conclusion the results of the present study suggest that altered expression of VEGFA and PLGF genes in placenta disturb the angiogenesis and contribute to the pathogenesis of recurrent pregnancy loss.

Immunological parameters of maternal peripheral blood as predictors of future pregnancy outcomes in patients with unexplained recurrent pregnancy loss

INTRODUCTION

Unexplained recurrent pregnancy loss (URPL), affecting approximately 1%-5% of women, exhibits a strong association with various maternal factors, particularly immune disorders. However, accurately predicting pregnancy outcomes based on the complex interactions and synergistic effects of various immune parameters without an automated algorithm remains challenging.

MATERIAL AND METHODS

In this historical cohort study, we analyzed the medical records of URPL patients treated at Xiangya Hospital, Changsha, China, between January 2020 and October 2022. The primary outcomes included clinical pregnancy and miscarriage. Predictors included complement, autoantibodies, peripheral lymphocytes, immunoglobulins, thromboelastography findings, and serum lipids. Least absolute shrinkage and selection operator (LASSO) analysis and logistic regression analysis was performed for model development. The model's performance, discriminatory, and clinical applicability were assessed using area under the curve (AUC), calibration curve, and decision curve analysis, respectively. Additionally, models were visualized by constructing dynamic and static nomograms.

RESULTS

In total, 502 patients with URPL were enrolled, of whom 291 (58%) achieved clinical pregnancy and 211 (42%) experienced miscarriage. Notable differences in complement, peripheral lymphocytes, and serum lipids were observed between the two outcome groups. Moreover, URPL patients with elevated peripheral NK cells (absolute counts and proportion), decreased complement levels, and dyslipidemia demonstrated a significantly increased risk of miscarriage. Four models were developed in this study, of which Model 2 demonstrated superior performance with only seven predictors, achieving an AUC of 0.96 (95% CI: 0.93-0.99) and an accuracy of 0.92. A web-based platform was established to visually present model 2 and to facilitate its utilization by clinicians in outpatient settings (available from: https://yingrongli.shinyapps.io/liyingrong/).

CONCLUSIONS

Our findings suggest that the implementation of such prediction models could serve as valuable tools for providing comprehensive information and facilitating clinicians in their decision-making processes.

Prevalence of karyotype alterations in couples with recurrent pregnancy loss in a tertiary center in Brazil

Objective

To assess the prevalence and type of chromosomal abnormalities in Brazilian couples with recurrent pregnancy loss (RPL) and compare the clinical characteristics of couples with and without chromosome abnormalities.

Methods

We assessed the medical records of 127 couples with a history of two or more miscarriages, referred to a tertiary academic hospital in Belo Horizonte, Brazil, from January 2014 to May 2023. Karyotype was generated from peripheral blood lymphocyte cultures, and cytogenetic analysis was performed according to standard protocols by heat-denatured Giemsa (RHG) banding.

Results

Abnormal karyotypes were detected in 10 couples (7.8%). The prevalence of chromosomal abnormalities was higher among females (6.3%) compared to males (2.0%), but this difference was not statistically significant (p=0.192). The mean number of miscarriages was. 3.3 ± 1.1 in couples with chromosome abnormalities and 3.1 ± 1.5 in couples without chromosome abnormalities (p=0.681). Numerical chromosomal anomalies (6 cases) were more frequent than structural anomalies. Four women presented low-grade Turner mosaicism. No differences were found between couples with and without karyotype alterations, except for maternal age, which was higher in the group with chromosome alterations.

Conclusion

The prevalence of parental chromosomal alterations in our study was higher than in most series described in the literature and was associated with increased maternal age. These findings suggest that karyotyping should be part of the investigation for Brazilian couples with RPL, as identifying the genetic etiology may have implications for subsequent pregnancies.

Low-molecular-weight heparin in the prevention of unexplained recurrent miscarriage: a systematic review and meta-analysis

The etiology of recurrent pregnancy loss (RPL) is complex and multifactorial and in half of patients it remains unexplained (U-RPL). Recently, low-molecular-weight heparin (LMWH) has gained increasing relevance for its therapeutic potential. On this regard, the aim of this systematic review and meta-analysis is to analyze the efficacy of low molecular weight heparin (LMWH) from the beginning of pregnancy in terms of live birth rates (LBR) in U-RPL. Registered randomized controlled trials (RCTs) were included. We stratified findings based on relevant clinical factors including number of previous miscarriages, treatment type and control type. Intervention or exposure was defined as the administration of LMWH alone or in combination with low-dose aspirin (LDA). A total of 6 studies involving 1016 patients were included. The meta-analysis results showed that LMWH used in the treatment of U-RPL was not associated with an increase in LBR with a pooled OR of 1.01, a medium heterogeneity (26.42%) and no publication bias. Results of other sub-analyses according to country, treatment type, and control type showed no significant effect of LMWH on LBR in all subgroups, with a high heterogeneity. The results highlight a non-significant effect of LMWH in U-RPL on LBR based on moderate quality evidence.Registration number: PROSPERO: ( https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022326433 ).

ANXA5 and VEGFA Gene Variants in Women with Early Pregnancy Losses from North Macedonia

Early pregnancy loss (EPL) is the most common pregnancy complication, found in approximately 15% of all clinically recognized pregnancy complications. Up to date, various maternal as well as fetal factors are reported as a cause of EPLs. However, in approximately 50% of EPL cases, the exact cause is not clearly identified and these cases are referred as idiopathic. The aim of our study was to examine the association of four distinct variants in the ANXA5 gene and two variants within the VEGFA gene in a cohort of women with EPLs from North Macedonia. This group was compared to a control group of women matched by ethnic background without pregnancy loss and at least one live birth. We also aimed to establish an effective and cost-efficient method for their detection based on multiplex single-base extension. Among 190 women experiencing EPLs, and 190 samples from women without a history of pregnancy loss (control group), our results demonstrated a statistically significant prevalence of heterozygotes for the M2/ANXA5 haplotype in women with EPLs, compared to the control group (p=0.0006). In the analyses comparing genotypic frequencies for the variants in the VEGFA gene, higher frequencies were generally observed among women experiencing EPLs, however without statistical significance. Our study aligns with multiple studies showing that M2 and M1 ANXA5 haplotypes are more prevalent in patients with pregnancy loss and presents an affordable genotyping technique for the specific ANXA5 and VEGFA variants.

Causal Relationship Between Circulating Immune Cells and Recurrent Spontaneous Abortion: A Bidirectional Mendelian Randomization Study

BACKGROUND

Recurrent spontaneous abortion (RSA) is a serious and common complication of pregnancy caused by multiple factors. The etiology remains incompletely understood, but immunologic factors play important roles. Here, we aimed to evaluate whether circulating immune cells causally impacted RSA.

METHODS

In this study, we conducted a comprehensive two-sample Mendelian randomization (MR) study to determine the causal association between the 731 immunophenotypes of human peripheral blood lymphocytes and the number of spontaneous abortions as well as recurrent miscarriage. Sensitivity analyses were performed to assess and minimize heterogeneity and horizontal pleiotropy. Reverse MR analysis was used to assess reverse causality.

RESULTS

After Bonferroni-correction, eight immunophenotypes were significantly associated with the number of spontaneous abortions: FSC-A on CD4+ T cell (beta = -0.051, 95% CI = [-0.085, -0.017], P-value = 0.004), CD8 on HLA DR+ CD8+ T cell (beta = -0.040, 95% CI = [-0.067, -0.014], P-value = 0.003), HLA DR on CD33dim HLA DR+ CD11b- (beta = -0.021, 95% CI = [-0.036, -0.005], P-value = 0.010), HLA DR+ T cell Absolute Count (beta = 0.022, 95% CI = [0.006, 0.037], P-value = 0.008), HLA DR+ T cell % lymphocyte (beta = 0.026, 95% CI = [0.010, 0.041], P-value = 0.001), HLA DR+ T cell % T cell (beta = 0.023, 95% CI = [0.007, 0.039], P-value = 0.004), HLA DR+ CD4+ T cell % lymphocyte (beta = 0.034, 95% CI = [0.007, 0.060], P-value = 0.012), and HLA DR on B cell (beta = 0.012, 95% CI = [0.003, 0.021], P-value = 0.010). In addition, we identified two immunophenotypes associated with recurrent miscarriage: HLA DR on B cell (OR = 0.854, 95% CI = [0.757, 0.964], P-value = 0.011), and CD19 on naive-mature B cell (OR = 4.595, 95% CI = [1.674, 12.617], P-value = 0.003). There was no evidence of heterogeneity, horizontal pleiotropy and reverse causality.

CONCLUSIONS

Our study demonstrated a tight link between adaptive immune cells and RSA through genetic means, thus providing potential therapeutic targets or novel diagnostic biomarkers.