Comparison and appraisal of (inter)national recurrent pregnancy loss guidelines

The effect and mechanism of low-molecular-weight heparin on the decidualization of stromal cells in early pregnancy

OBJECTIVE

This study aimed to analyze the effect of low-molecular-weight heparin (LMWH) on the decidualization of stromal cells in early pregnancy and explore the effect of LMWH on pregnancy outcomes.

METHODS

Recurrent spontaneous abortion (RSA) mouse model (CBA/J × DBA/2) and normal pregnant mouse model (CBA/J × BALB/c) were established. The female mice were checked for a mucus plug twice daily to identify a potential pregnancy. When a mucus plug was found, conception was considered to have occurred 12 h previously. The pregnant mice were divided randomly into a normal pregnancy control group, an RSA model group, and an RSA + LMWH experimental group (n = 10 mice in each group). Halfway through the 12th day of pregnancy, the embryonic loss of the mice was observed; a real-time quantitative polymerase chain reaction was used to detect the messenger ribonucleic acid (mRNA) expressions of prolactin (PRL) and insulin-like growth factor-binding protein 1 (IGFBP1) in the decidua of the mice. Additionally, the decidual tissues of patients with RSA and those of normal women in early pregnancy who required artificial abortion were collected and divided into an RSA group and a control group. Decidual stromal cells were isolated and cultured to compare cell proliferation between the two groups, and cellular migration and invasion were detected by membrane stromal cells. Western blotting was used to detect the protein expressions of proliferating cell nuclear antigen (PCNA), cyclin D1, matrix metalloproteinase- (MMP) 2, and MMP-7 in stromal cells treated with LMWH.

RESULTS

Compared with the RSA group, LMWH significantly reduced the pregnancy loss rate in the RSA mice (p < 0.05). Compared with the RSA group, the LMWH + RSA group had significantly higher expression levels of PRL and IGFBP1 mRNA (p < 0.01). LMWH promoted the proliferation, migration, and invasion of human decidual stromal cells; compared with the control group, the expression levels of MMP-2, MMP-7, cyclin D1, and PCNA proteins in the decidual stromal cells of the LMWH group increased (p < 0.05).

CONCLUSIONS

The use of LMWH can improve pregnancy outcomes by enhancing the proliferation and migration of stromal cells in early pregnancy and the decidualization of stromal cells.

Assessing causal relationships between gut microbiota and abortion: evidence from two sample Mendelian randomization analysis

Background

While some studies have suggested a link between gut microbiota (GM) and abortion, the causal relationship remains unclear.

Methods

To explore the causal relationship between GM and abortion, including spontaneous abortion (SA) and habitual abortion (HA), we performed a two-sample Mendelian randomization (MR) analysis. We used summary statistics data from MiBioGen and FinnGen for genome-wide association studies (GWAS), with GM data as the exposure variable and abortion data as the outcome variable.

Results

In the absence of heterogeneity and horizontal pleiotropy, the inverse-variance weighted (IVW) method identified five genetically predicted GM genera linked to the risk of abortions. Lactococcus was negatively correlated with the risk of SA, whereas the Eubacterium fissicatena group was positively correlated with the risk of SA. Genetic predictions of Coprococcus3 and Odoribacter were linked to a reduced risk of HA, while the Eubacterium ruminantium group was associated with an increased risk of HA.

Conclusion

Our study suggests a genetic causal relationship between specific GM and two types of abortions, improving our understanding of the pathological relationship between GM and abortion.

Effect of anti-thyroid antibodies on recurrent miscarriage: A meta-analysis

SETTING

Previous studies addressed the association between anti-thyroid antibodies and recurrent miscarriage (RM), however, the role of anti-thyroid antibodies in RM patients is debatable.

OBJECTIVES

Therefore, we conducted this meta-analysis and the aim of this current study was to assess whether anti-thyroid peroxidase (anti-TPO) and/or anti-thyroglobulin (anti-TG) antibody positivity was associated with RM.

DESIGN

A meta-analysis was conducted.

PARTICIPANTS

Recurrent miscarriage patients.

METHODS

STATA 12.0 software were applied to compute odds ratios (ORs)/relative risks (RRs) and 95% CIs regarding association between anti-TPO and anti-TG antibodies and the prevalence of RM.

RESULTS

N = 28 studies (8875 participants) explored effect of anti-thyroid antibodies on RM. Analysis of the 28 studies revealed significant association between anti-TPO, anti-TG antibodies and the prevalence of RM with a random effects model (OR/RR = 2.02; 95% CI: 1.63-2.51, p < 0.001; I2 = 44.3%, p value for Q test = 0.004). Analysis of the 20 studies revealed significant association between anti-TPO antibodies and the prevalence of RM with a random effects model (OR/RR = 1.59; 95% CI: 1.25-2.03, p < 0.001; I2 = 43.1%, p value for Q test = 0.022). Analysis of the 14 studies revealed significant association between anti-TG antibodies and the prevalence of RM with a random effects model (OR/RR = 2.25; 95% CI: 1.56-3.23, p < 0.001; I2 = 49.2%, p value for Q test = 0.019).

CONCLUSIONS

Based on the currently available analysis, our findings suggest that women with anti-TPO and/or anti-TG antibodies have a higher risk of RM than that in negative antibody women. Further investigation is needed to better clarify the exact role of the anti-thyroid antibodies in RM and whether treatment is of benefit.

LIMITATIONS

First, differences from various detection methods and reagents used in different studies may affect the diagnostic interpretation of anti-thyroid antibodies, which might influence the accuracy of this meta-analysis. Second, positive anti-thyroid antibodies seem likely to be part of a more general disorder of maternal immune system, due to restrictions of funding and condition, a complete autoantibody screening investigation is hardly to conduct in all participants, and this could be a possible limitation of all included studies. Third, there is no mention of thyroxine therapy on RM, making the meta-analysis even more limited.

A new prognostic model for recurrent pregnancy loss: assessment of thyroid and thromboelastograph parameters

Objective

This study aimed to identify predictors associated with thyroid function and thromboelastograph (TEG) examination parameters and establish a nomogram for predicting the risk of subsequent pregnancy loss in recurrent pregnancy loss (RPL).

Methods

In this retrospective study, we analyzed the medical records of 575 RPL patients treated at Lanzhou University Second Hospital, China, between September 2020 and December 2022, as a training cohort. We also included 272 RPL patients from Ruian People's Hospital between January 2020 and July 2022 as external validation cohort. Predictors included pre-pregnancy thyroid function and TEG examination parameters. The study outcome was pregnancy loss before 24 weeks of gestation. Variable selection was performed using least absolute shrinkage and selection operator regression and stepwise regression analyses, and the prediction model was developed using multivariable logistic regression. The study evaluated the model's performance using the area under the curve (AUC), calibration curve, and decision curve analysis. Additionally, dynamic and static nomograms were constructed to provide a visual representation of the models.

Results

The predictors used to develop the model were body mass index, previous pregnancy losses, triiodothyronine, free thyroxine, thyroid stimulating hormone, lysis at 30 minutes, and estimated percent lysis which were determined by the multivariable logistic regression with the minimum Akaike information criterion of 605.1. The model demonstrated good discrimination with an AUC of 0.767 (95%CI 0.725-0.808), and the Hosmer-Lemeshow test indicated good fitness of the predicting variables with a P value of 0.491. Identically, external validation confirmed that the model exhibited good performance with an AUC of 0.738. Moreover, the clinical decision curve showed a positive net benefit in the prediction model. Meanwhile, the web version we created was easy to use. The risk stratification indicated that high-risk patients with a risk score >147.9 had a higher chance of pregnancy loss (OR=6.05, 95%CI 4.09-8.97).

Conclusions

This nomogram well-predicted the risk of future pregnancy loss in RPL and can be used by clinicians to identify high-risk patients and provide a reference for pregnancy management of RPL.

Systematic review and meta-analysis of association between plasminogen activator inhibitor-1 4G/5G polymorphism and recurrent pregnancy loss: an update

BACKGROUND

We conducted this systematic review and meta-analysis to better understand the association between rs1799762 PAI-1 gene polymorphism and the risk of RPL.

METHODS

A systematic search for studies that assessed the association between PAI-1 4G/5G polymorphism and RPL risk published in search sources, PubMed/Medline, ISI Web of Knowledge, Scopus, and Google Scholar till January 2024 was conducted.

RESULTS

There were 23 case-control studies in total, with a high degree of statistical heterogeneity among them which indicated the need for subgroup analysis. We found a significant positive association between the risk of RPL and 4G/4G PAI-1 (OR: 2.57; 95% CI: 1.69-3.90), likewise 4G/5G (OR: 2/02 95% CI: 1.39-2.92) and mixed genotype (4G/4G+4G/5G) (OR: 2.31 95% CI: 1.81-2.93). Considering the ethnicity, the 4G/4G polymorphism is significantly associated with Asian descent (OR: 2.10; CI: 1.65-2.69) while the strong association (OR: 6.47; CI: 3.23-12.97) observed in the Greater Middle East descent is not statistically significant (P=0.16). PAI-1 4G/5G polymorphism association with RPL was only significant in Greater Middle East descent (OR: 2.93; CI: 2.41-3.56), and mixed genotype was significantly associated with RPL in Asian (OR: 2.37; CI: 1.55-3.61), Greater Middle East (OR: 3.01; CI: 2.16-4.19), and European populations (OR: 1.38; CI: 0.91-2.10). The association between RPL and PAI-1 4G/4G was significant for RPLs both under 12 weeks (OR: 1.82; 95% CI: 1.34-2.47), and under 24 weeks (OR: 1.46; 95% CI: 1.11-1.92), while considering heterozygote form the association was only significant for RPLs under 24 weeks (OR: 1.91; 95% CI: 1.58-2.31). Regarding the mixed genotype, there is a significant positive association between PAI-1 and RPL for RPLs under 12 weeks (OR: 2.09; 95% CI: 1.49-2.93), and under 24 weeks (OR: 2.10; 95% CI: 1.52-2.92).

CONCLUSIONS

Our findings indicate a significant association between the rs1799762 PAI-1 polymorphism and the risk of RPL.

Maternal-fetal immunity and recurrent spontaneous abortion

Recurrent Spontaneous Abortion (RSA) is a common pregnancy complication, that has multifactorial causes, and currently, 40%-50% of cases remain unexplained, referred to as Unexplained RSA (URSA). Due to the elusive etiology and mechanisms, clinical management is exceedingly challenging. In recent years, with the progress in reproductive immunology, a growing body of evidence suggests a relationship between URSA and maternal-fetal immunology, offering hope for the development of tailored treatment strategies. This article provides an immunological perspective on the pathogenesis, diagnosis, and treatment of RSA. On one hand, it comprehensively reviews the immunological mechanisms underlying RSA, including abnormalities in maternal-fetal interface immune tolerance, maternal-fetal interface immune cell function, gut microbiota-mediated immune dysregulation, and vaginal microbiota-mediated immune anomalies. On the other hand, it presents the diagnosis and existing treatment modalities for RSA. This article offers a clear knowledge framework for understanding RSA from an immunological standpoint. In conclusion, while the "layers of the veil" regarding immunological factors in RSA are gradually being unveiled, our current research may only scratch the surface. In terms of immunological etiology, effective diagnostic tools for RSA are currently lacking, and the efficacy and safety of immunotherapies, primarily based on lymphocyte immunotherapy and intravenous immunoglobulin, remain contentious.

Depression, anxiety, and stress and adverse pregnancy outcomes in pregnant women with history of recurrent pregnancy loss in Nigeria

OBJECTIVE

The primary purpose of this study was to examine whether pregnant women with a history of recurrent pregnancy loss (RPL) are more likely to experience moderate-to-severe depression, anxiety, or stress symptoms than pregnant women without a history of RPL. The secondary purpose was to determine whether women with prior RPL experienced more unfavorable pregnancy outcomes if they had depression, anxiety, or stress.

METHODS

A prospective case-control study was conducted that included 47 pregnant women with a history of RPL and 94 pregnant women without prior RPL. Participants 20 weeks of gestation or earlier were included. Both groups completed the Depression, Anxiety, and Stress Scale (DASS-21), and were followed up until delivery to determine the pregnancy outcomes. Multivariate logistic regression was used to compare adverse pregnancy outcomes.

RESULT

Among the 47 women with prior RPL, 10 had primary RPL (two or more miscarriages without a successful pregnancy) and 37 secondary RPL (two or more miscarriages with a history of successful pregnancy). RPL was significantly associated with moderate-to-severe levels of depression (P < .001), anxiety (P < .001), and stress (P < .001). Among the RPL group, high stress level was significantly associated with repeat miscarriage (adjusted odds ratio (AOR) = 5.28, 95%CI = 1.25-100.0, P = .03) and preterm labor (AOR = 6.07, 95%CI = 1.61-100.0, P = .04). Depression and anxiety were not associated with adverse pregnancy outcomes.

CONCLUSION

Pregnant women with a history of RPL had considerably higher rates of moderate-to-severe depression, anxiety, and stress. Repeat miscarriage and preterm labor were considerably higher among pregnant women with RPL who were experiencing high stress levels at baseline.

The relevance of prothrombotic genetic variants in women who experienced pregnancy loss or embryo implantation failure: A retrospective analysis of 1922 cases

OBJECTIVE

The aim of our study was that to assess the allelic and genotype frequencies of nine prothrombotic gene variants in patients with a history of pregnancy loss and recurrent pregnancy loss (RPL). Women who underwent assisted reproductive technology (ART) with ongoing pregnancy and those with recurrent implantation failure (RIF) were also included.

METHODS

Nine prothrombotic gene variants were evaluated: factor V Leiden (FVL), factor V, H1299R variant (FVR2), factor II (FII) G20210A, methylene-tetrahydrofolate reductase (MTHFR) C677T and A1298C, beta-fibrinogen -455G>A, factor XIII (FXIII) V34L, human platelet antigen-1 (HPA-1) L33P variants, and plasminogen activator inhibitor-1 (PAI-1) 4G/5G. The following study groups were assessed: (1) women who experienced one (n = 334) or two (n = 264) episodes of pregnancy loss; (2) 468 women who experienced RPL; (3) 214 women who underwent ART followed by ongoing pregnancies; and (4) 282 women who experienced RIF after ART, that is, three or more consecutive implantation failures following high-quality embryo transfers to the uterus with an appropriate endometrium. As control group, 430 subjects from the general population were enrolled.

RESULTS

FVL, the -455G>A variant of beta-fibrinogen, and PAI-1 4G were associated with a higher risk of developing RPL compared with the general population. Furthermore, FVL, FVR2, FII G20210A and MTHFR C677T conferred a significantly higher risk of RIF in women who performed ART compared with the general population. No statistical differences between the general population and other study groups were observed.

CONCLUSIONS

Specific prothrombotic genetic variants are more frequently expressed in women with RPL and RIF, supporting their role in the development of polimicrothrombosis and impairing the invasion during embryo implantation.

Meta-analysis of FOXP3 polymorphisms and recurrent spontaneous abortion susceptibility

BACKGROUND

The polymorphisms of the FOXP3 gene may mediate abnormalities in Tregs, leading to an imbalance in maternal-fetal immune tolerance and ultimately resulting in recurrent spontaneous abortion (RSA). This meta-analysis aims to assess the potential association between FOXP3 polymorphisms and susceptibility to RSA using five specific single nucleotide polymorphisms (SNPs).

MATERIALS AND METHODS

By conducting a comprehensive search across databases such as EMBASE, PubMed, Web of Science, Cochrane Library, CNKI, Wanfang, and CBM, we identified suitable studies for inclusion in the meta-analysis. The data extracted from these studies were subjected to analysis using Stata SE 15. To assess the degree of association, we utilized the odds ratio (OR) along with its corresponding 95% confidence intervals (CI). Five specific single nucleotide polymorphisms (SNPs) were employed in assessing the connection between FOXP3 gene polymorphisms and RSA.

RESULTS

The meta-analysis demonstrated a significant association between several polymorphisms (rs3761548, rs2232365, rs2232368, rs2280883, and rs2294021) and susceptibility to RSA. Conversely, the FOXP3 rs5902434 polymorphism was not associated with susceptibility to RSA.

CONCLUSION

Our meta-analysis suggests that these genetic variations within the FOXP3 gene might play a role in the progression of RSA disease. Meanwhile, large-scale studies that consider multiple factors are needed to validate this finding.

To Test or Not to Test: Routine Thrombophilia Diagnostic Screening of Women with Reproductive Failures

BACKGROUND

Recurrent reproductive failure is a global health issue affecting a significant number of women. Thrombophilias have been implicated as a possible cause. Inherited thrombophilias include a single nucleotide variant on factor V Leiden and prothrombin.

OBJECTIVE

The aim of this study was to evaluate the association between the following single nucleotide variants: factor V Leiden (c.1601G>A), the prothrombin gene (c.*97G>A) and the reproductive failure in the Polish population.

METHODS

The study was conducted in a group of 545 patients with recurrent pregnancy loss, RPL (≥2 miscarriages), and in a group of 641 patients with infertility. The distribution of genotypes for the selected variants were determined by RFLP-PCR and by the real-time PCR method.

RESULTS

A variant of the F5 gene was found in 5.14% of patients with RPL and in 6.08% of infertile women. A variant of the F2 gene was identified in 0.73% of patients with RPL and in 2.03% of women with infertility. The frequency in the study groups did not differ from that in the general population. No association between the studied variants of the F5 gene or the F2 gene and the predisposition to reproductive wastage was found.

CONCLUSIONS

Recommendations for routine thrombophilia testing in women with recurrent miscarriages should be revisited. The decision regarding testing should be made individually depending on additional factors indicating an increased risk of venous thromboembolism.

Polymorphisms of ACE and thrombophilic genes: risk for recurrent pregnancy loss

BACKGROUND

Recurrent pregnancy loss (RPL) affects up to 5% of pregnancies, but with no consensus on the definition. Inherited thrombophilia has been postulated as a risk factor for RPL. The aim of this study was to investigate the association of RPL with polymorphisms of five genes that influent the coagulation and fibrinolysis.

METHODS

This study was conducted on total of 224 women, 129 women with ≥2 early RPL or ≥1 late pregnancy loss, 95 women with at least two normal life births and no history of pregnancy loss. Five gene polymorphisms F2 20 210G>A (rs1799963), F5 1691G>A (rs6025), MTHFR 677C>T (rs1801133), SERPINE1 -675 4G/5G (rs1799762) and ACE I/D (rs1799752) were genotyped by PCR-based methods.

RESULTS

A significant relationship was found between SERPINE1 4G/4G and ACE D/D polymorphisms and RPL (p<0.001 both, OR 2.91 and 3.02, respectively). In contrast, no association was found between F2 20 210G>A, F5 1691G>A and MTHFR 677C>T polymorphisms and risk for RPL. A combination of hypofibrinolytic homozygotes SERPINE1 4G/4G+ACE D/D was observed as a highly associated with RPL (Cochran-Armitage test, p<0.001), and their strong independent association with RPL risk was confirmed by logistic regression analysis (both p values <0.001, OR 3.35 and 3.43, respectively).

CONCLUSION

Our data have demonstrated that SERPINE1 and ACE gene polymorphisms, individually or in combination, appear to be a significant risk for RPL. This data may be useful in adding to the knowledge on inherited thrombophilia as an important contributor to RPL pathogenesis.

Comprehensive bioinformation analysis of differentially expressed genes in recurrent pregnancy loss

Recurrent pregnancy loss (RPL) occurs frequently, and its causes are complex. The aetiology of nearly 50% of RPL cases is still unknown. This study aimed to ascertain differentially expressed genes (DEGs) and pathways by comprehensive bioinformatics analysis. We downloaded the gene expression microarray of GSE165004 from the Gene Expression Omnibus (GEO). Gene ontology (GO) analysis and Kyoto Encyclopaedia of Gene and Genome (KEGG) pathway enrichment analyses were performed on selected genes by using the R Programming Language. A protein-protein interaction (PPI) network was constructed with the Retrieval of Interacting Genes (STRING). Our analysis revealed that 1,869 genes were differentially expressed in RPL and control groups. GO analysis revealed that the interferon type 1 and the glycoprotein-related biological processes played irreplaceable roles, meanwhile KEGG enrichment analysis also revealed that the cAMP signalling pathway and the prolactin signalling pathway played important roles. In the following study, we found that there were many DEGs in the RPL group that were closely related to endometrial decidualization, such as IL17RD, IL16, SOX4, CREBBP, and POFUT1 as well as Notch1 and RBPJ in the Notch signalling pathway family were down-regulated in the RPL group. The results provided valuable information on the pathogenesis of RPL.

Epidemiology of spontaneous pregnancy loss in Kazakhstan: A national population-based cohort analysis during 2014-2019 using the national electronic healthcare system

INTRODUCTION

Spontaneous pregnancy loss (SPL) is a common health problem that affects 1:10 of childbearing women, and is linked with physical and psychological complications. As the number of nationwide studies on the incidence of SPL is few, especially from middle-income countries, in this study we investigated the epidemiology, complications and outcomes of SPL before 22 weeks of gestation by analyzing large-scale healthcare data from the Unified Nationwide Electronic Healthcare System (UNEHS) in Kazakhstan.

MATERIAL AND METHODS

A population-based study among women who experienced SPL in any healthcare setting of the Republic of Kazakhstan during the period of 2014-2019. The International Classification of Diseases (ICD) 10th edition and ICD 9th edition's procedural codes were utilized to retrieve data using relevant diagnostic and procedural codes.

RESULTS

In total, 207 317 records of women who have experienced an SPL before 22 weeks of gestation were analyzed from all Kazakhstani regions. The estimated prevalence of SPL was 8.7%, with a 20% decline over a 6-year period. The SPL cases ratio comprises on average 6.2 per 1000 reproductive-age women. Incomplete miscarriage (ICD-10 code "O03.4") was the most common type (37.8%), followed by blighted ovum (ICD-10 code "O02.0"; 34.1%) and missed abortion (ICD-10 code "O02.1"; 13.5%). The most common management methods were dilation and curettage of the uterus (ICD-9 code "69.0"; 84.7%) and aspiration curettage of the uterus (ICD-9 code "65.0"; 15%), whereas medical management was rarely performed (2.6%).

CONCLUSION

The information available in UNEHS adequately identifies types of miscarriages and treatment methods. Although the prevalence of SPL before 22 weeks of gestation is decreasing, management of miscarriages requires closer attention.

Biogenesis and function of exosome lncRNAs and their role in female pathological pregnancy

Preeclampsia, gestational diabetes mellitus, and recurrent spontaneous abortion are common maternal pregnancy complications that seriously endanger women's lives and health, and their occurrence is increasing year after year with a rejuvenation trend. In contrast to biomarkers found freely in tissues or body fluids, exosomes exist in a relatively independent environment and provide a higher level of stability. As backbone molecules, guidance molecules, and signaling molecules in the nucleus, lncRNAs can regulate gene expression. In the cytoplasm, lncRNAs can influence gene expression levels by modifying mRNA stability, acting as competitive endogenous RNAs to bind miRNAs, and so on. Exosomal lncRNAs can exist indefinitely and are important in intercellular communication and signal transduction. Changes in maternal serum exosome lncRNA expression can accurately and timely reflect the progression and regression of pregnancy-related diseases. The purpose of this paper is to provide a reference for clinical research on the pathogenesis, diagnosis, and treatment methods of pregnancy-related diseases by reviewing the role of exosome lncRNAs in female pathological pregnancy and related molecular mechanisms.

Identifying discrepancies between clinical practice and evidence-based guideline in recurrent pregnancy loss care, a tool for clinical guideline implementation

BACKGROUND

Practice variation in recurrent pregnancy loss (RPL) care is common. International guidelines vary in their recommendations for the management of RPL couples, which could lead to an increase of cross border reproductive care. Currently, the Dutch RPL guideline is being adapted from the European Society for Human Reproduction and Embryology (ESHRE) guideline. We aim to identify discrepancies between RPL guidelines and RPL practice. These discrepancies could be considered in the development of a new guideline and implementation strategies to promote adherence to new recommendations.

METHODS

A nationwide survey on the management of RPL patients was conducted across all 107 hospital-based obstetrics and gynaecology practices in the Netherlands. The survey was sent via the Dutch Society for Obstetricians and Gynaecologists to all affiliated clinicians. The questionnaire consisted of 36 questions divided in four sections: clinician's demographics, RPL definition, investigations and therapy. The data were compared to the recommendations given by the Dutch national guideline and the most recent guideline of the ESHRE.

RESULTS

All hospital-based practices (100%; n = 107) filled in the online questionnaire. The majority of respondents defined RPL similarly, as two or more pregnancy losses (87.4%), not obligatory consecutive (93.1%). More than half of respondents routinely perform thrombophilia screening ( 58%), although not advised by the ESHRE, while thyroid function (57%), thyroid auto-immunity (27%) and β2-glycoprotein antibodies (42%) in the context of antiphospholipid syndrome (APS) are recommended but investigated less often. Regarding parental karyotyping, 20% of respondents stated they always perform parental karyotyping, without prior risk assessment. because of RPL. Treatment for hereditary thrombophilia was frequently (43.8% (n = 137)) prescribed although not recommended. And finally, a considerable part (12-16%) of respondents prescribe medication in case of unexplained RPL.

CONCLUSION

While many clinicians perform investigations recommended by the ESHRE, there is a considerable variation of RPL practice in the Netherlands. We identified discrepancies between RPL guidelines and RPL practice, providing possibilities to focus on multifaceted implementation strategies, such as educational intervention, local consensus processes and auditing and feedback. This will improve the quality of care provided to RPL patients and may diminish the necessity felt by patients to turn to multiple opinions or cross border reproductive care.

Recurrent Pregnancy Loss Etiology, Risk Factors, Diagnosis, and Management. Fresh Look into a Full Box

Recurrent pregnancy loss is a complex health challenge with no universally accepted definition. Inconsistency in definitions involves not only the number of spontaneous abortions (two or three) that are accepted for recurrent pregnancy loss but the types of pregnancy and gestational age at miscarriage. Due to the heterogeneity of definitions and criteria applied by international guidelines for recurrent pregnancy loss, the true incidence of recurrent miscarriage, which is reported to range from 1% to 5%, is difficult to estimate. Moreover, the exact etiology of recurrent pregnancy loss remains questionable; thus, it is considered a polyetiological and multifactorial condition with many modifiable and non-modifiable factors involved. Even after thoroughly evaluating recurrent pregnancy loss etiology and risk factors, up to 75% of cases remain unexplained. This review aimed to summarize and critically analyze accumulated knowledge on the etiology, risk factors, relevant diagnostic options, and management approach to recurrent pregnancy loss. The relevance of various factors and their proposed roles in recurrent pregnancy loss pathogenesis remains a matter of discussion. The diagnostic approach and the management largely depend on the etiology and risk factors taken into consideration by a healthcare professional as a cause of recurrent miscarriage for a particular woman or couple. Underestimation of social and health consequences of recurrent pregnancy loss leads to compromised reproductive health and psychological well-being of women after miscarriage. Studies on etiology and risk factors for recurrent pregnancy loss, especially idiopathic, should be continued. The existing international guidelines require updates to assist clinical practice.

Diagnostic factors for recurrent pregnancy loss: an expanded workup

PURPOSE

There is limited information on the risk factors for recurrent pregnancy loss (RPL).

METHODS

In this study, a patient-based approach was used to investigate the possible involvement and relative relevance of a large number of diagnostic factors in 843 women with RPL who underwent an extensive diagnostic workup including 44 diagnostic factors divided into 7 major categories.

RESULTS

The rates of abnormalities found were: (1) genital infections: 11.74%; (2) uterine anatomic defects: 23.72%; (3) endocrine disorders: 29.42%; (4) thrombophilias: 62%; (5) autoimmune abnormalities: 39.2%; (6) parental karyotype abnormalities 2.25%; (7) clinical factors: 87.78%. Six hundred and fifty-nine out of eight hundred and forty-three women (78.17%) had more than one abnormality. The mean number of pregnancy losses increased by increasing the number of the abnormalities found (r = 0.86949, P < 0.02). The factors associated with the highest mean number of pregnancy losses were cervical isthmic incompetence, anti-beta-2-glycoprotein-1 antibodies, unicornuate uterus, anti-prothrombin A antibodies, protein C deficiency, and lupus anticoagulant. The majority of the considered abnormalities had similar, non-significant prevalence between women with 2 versus ≥ 3 pregnancy losses with the exception of age ≥ 35 years and MTHFR A1298C heterozygote mutation. No difference was found between women with primary and secondary RPL stratified according to the number of abnormalities detected (Chi-square: 8.55, P = 0.07). In these women, the only factors found to be present with statistically different rates were age ≥ 35 years, cigarette smoking, and genital infection by Ureaplasma.

CONCLUSION

A patient-based diagnostic approach in women with RPL could be clinically useful and could represent a basis for future research.

Cell-free fetal DNA for genetic evaluation in Copenhagen Pregnancy Loss Study (COPL): a prospective cohort study

BACKGROUND

One in four pregnancies end in a pregnancy loss. Although the effect on couples is well documented, evidence-based treatments and prediction models are absent. Fetal aneuploidy is associated with a higher chance of a next successful pregnancy compared with euploid pregnancy loss in which underlying maternal conditions might be causal. Ploidy diagnostics are therefore advantageous but challenging as they require collection of the pregnancy tissue. Cell-free fetal DNA (cffDNA) from maternal blood has the potential for evaluation of fetal ploidy status, but no large-scale validation of the method has been done.

METHODS

In this prospective cohort study, women with a pregnancy loss were recruited as a part of the Copenhagen Pregnancy Loss (COPL) study from three gynaecological clinics at public hospitals in Denmark. Women were eligible for inclusion if older than 18 years with a pregnancy loss before gestational age 22 weeks (ie, 154 days) and with an intrauterine pregnancy confirmed by ultrasound (including anembryonic sac), and women with pregnancies of unknown location or molar pregnancies were excluded. Maternal blood was collected while pregnancy tissue was still in situ or within 24 h after pregnancy tissue had passed and was analysed by genome-wide sequencing of cffDNA. Direct sequencing of the pregnancy tissue was done as reference.

FINDINGS

We included 1000 consecutive women, at the time of a pregnancy loss diagnosis, between Nov 12, 2020, and May 1, 2022. Results from the first 333 women with a pregnancy loss (recruited between Nov 12, 2020, and Aug 14, 2021) were used to evaluate the validity of cffDNA-based testing. Results from the other 667 women were included to evaluate cffDNA performance and result distribution in a larger cohort of 1000 women in total. Gestational age of fetus ranged from 35-149 days (mean of 70·5 days [SD 16·5], or 10 weeks plus 1 day). The cffDNA-based test had a sensitivity for aneuploidy detection of 85% (95% CI 79-90) and a specificity of 93% (95% CI 88-96) compared with direct sequencing of the pregnancy tissue. Among 1000 cffDNA-based test results, 446 (45%) were euploid, 405 (41%) aneuploid, 37 (4%) had multiple aneuploidies, and 112 (11%) were inconclusive. 105 (32%) of 333 women either did not manage to collect the pregnancy tissue or collected a sample classified as unknown tissue giving a high risk of being maternal.

INTERPRETATION

This validation of cffDNA-based testing in pregnancy loss shows the potential and feasibility of the method to distinguish euploid and aneuploid pregnancy loss for improved clinical management and benefit of future reproductive medicine and women's health research.

FUNDING

Ole Kirks Foundation, BioInnovation Institute Foundation, and the Novo Nordisk Foundation.

Prevalence and associated factors of recurrent pregnancy loss in Nigeria according to different national and international criteria (ASRM/ESHRE vs. WHO/RCOG)

Background

In low-and middle-income countries, no conclusive research explains the prevalence and associated factors of women with a history of recurrent pregnancy loss (RPL). Some authorities have recommended further scientific research on the effect of various definitions of RPL.

Objective

To assess prevalence and associated factors of RPL among pregnant women in Nigeria according to different national and international criteria: the American Society for Reproductive Medicine/ European Society for Human Reproduction and Embryology (ASRM/ESHRE; two losses) and the World Health Organization/ Royal College of Obstetricians and Gynecologists (WHO/RCOG; three consecutive losses) criteria.

Methods

This is a cross-sectional analytical study wherein, pregnant women with prior RPL were investigated. The outcome measures were prevalence and risk factors. The associations between independent variables and outcome variable were explored using bivariate and multivariable logistic regression models. The results of these analyses were reported as adjusted odds ratios (AORs) with 95% confidence intervals (95%CI). Factors associated with RPL were identified using multivariate regression models.

Result

Of the 378 pregnant women interviewed, the overall prevalence of RPL in this study was found to be 15.34% (95% confidence interval = 11.65%-19.84%). The prevalence of RPL was 15.34% (58/378; 95%CI = 11.65%-19.84%) and 5.29% (20/378; 95%CI = 3.23%-8.17) according to the ASRM and the WHO criterion respectively. Regardless of diagnostic criteria, unexplained (AOR = 23.04; 95%CI: 11.46-36.32), endocrine disturbances (AOR = 9.76; 95%CI: 1.61-63.19), uterine abnormalities (AOR = 13.57; 95%CI: 3.54-50.60), and antiphospholipid syndrome (AOR = 24.59; 95%CI: 8.45-71.04) were positively and independently associated with RPL. No significant risk factors were seen when the ASRM/ ESHRE criterion vs. WHO/RCOG criterion were compared. Advanced maternal age was significantly higher in secondary than in primary type of RPL.

Conclusion

The prevalence of RPL was 15.34% and 5.29% according to ASRM/ESHRE and WHO/RCOG criterion respectively, with secondary type predominating. No significant differences with regard to risk factors were seen according to diagnostic criteria studied, though advanced maternal age was significantly higher in secondary RPL. Further research is needed to confirm our findings and to better characterize the magnitude of differences.

The Update Immune-Regulatory Role of Pro- and Anti-Inflammatory Cytokines in Recurrent Pregnancy Losses

Recurrent pregnancy losses (RPL) is a common reproductive disorder with various underlying etiologies. In recent years, rapid progress has been made in exploring the immunological mechanisms for RPL. A propensity toward Th2 over Th1 and regulatory T (Treg) over Th17 immune responses may be advantageous for reproductive success. In women with RPL and animals prone to abortion, an inordinate expression of cytokines associated with implantation and early embryo development is present in the endometrium or decidua secreted from immune and non-immune cells. Hence, an adverse cytokine milieu at the maternal-fetal interface assaults immunological tolerance, leading to fetal rejection. Similar to T cells, NK cells can be categorized based on the characteristics of cytokines they secrete. Decidual NK (dNK) cells of RPL patients exhibited an increased NK1/NK2 ratio (IFN-γ/IL-4 producing NK cell ratios), leading to pro-inflammatory cytokine milieu and increased NK cell cytotoxicity. Genetic polymorphism may be the underlying etiologies for Th1 and Th17 propensity since it alters cytokine production. In addition, various hormones participate in cytokine regulations, including progesterone and estrogen, controlling cytokine balance in favor of the Th2 type. Consequently, the intricate regulation of cytokines and hormones may prevent the RPL of immune etiologies. Local or systemic administration of cytokines or their antagonists might help maintain adequate cytokine milieu, favoring Th2 over Th1 response or Treg over Th17 immune response in women with RPL. Herein, we provided an updated comprehensive review regarding the immune-regulatory role of pro- and anti-inflammatory cytokines in RPL. Understanding the roles of cytokines involved in RPL might significantly advance the early diagnosis, monitoring, and treatment of RPL.

Understanding recurrent pregnancy loss: recent advances on its etiology, clinical diagnosis, and management

Recurrent pregnancy loss (RPL) has become an important reproductive health issue worldwide. RPL affects about 2%-3% of reproductive-aged women, and makes serious threats to women's physical and mental health. However, the etiology of approximately 50% of RPL cases remains unknown (unexplained RPL), which poses a big challenge for clinical management of these patients. RPL has been widely regarded as a complex disease where its etiology has been attributed to numerous factors. Heretofore, various risk factors for RPL have been identified, such as maternal ages, genetic factors, anatomical structural abnormalities, endocrine dysfunction, prethrombotic state, immunological factors, and infection. More importantly, development and applications of next generation sequencing technology have significantly expanded opportunities to discover chromosomal aberrations and single gene variants responsible for RPL, which provides new insight into its pathogenic mechanisms. Furthermore, based upon patients' diagnostic evaluation and etiologic diagnosis, specific therapeutic recommendations have been established. This review will highlight current understanding and recent advances on RPL, with a special focus on the immunological and genetic etiologies, clinical diagnosis and therapeutic management.

A Systematic Review and Meta-Analysis of the Association between the FV H1299R Variant and the Risk of Recurrent Pregnancy Loss

This study evaluated the association between the H1299R factor V (FV) variant (rs1800595) and recurrent pregnancy loss (RPL). Pubmed (MEDLINE) and Embase (OVID) bibliographic databases were searched from the inception to 31 May 2022 to identify suitable articles according to PRISMA and MOOSE guidelines. We included observational studies, case-control studies, cross-sectional studies, and cohort studies reporting a numerical and well-distinguished Het or Hom status of the H1299R variant obtained through PCR or other biochemical techniques and comparing RPL patients with a healthy control group. The review protocol was registered at PROSPERO (CRD42022330077). Two authors independently screened studies, extracted data, and carried out the risk of bias assessment using the Newcastle Ottawa scale (NOS). A meta-analysis was performed with RevMan software Version 5.4 using an odds ratio (OR) with an M-H, random effect, and 95% CI. We included 13 clinical studies for a total of 1669 RPL patients and 1466 healthy women as a control group. H1299R variant was slightly associated with RPL albeit without significance (OR 1.18, 95% CI: 0.78-1.80, p = 0.44). Subgroup analyses considering H1299R in heterozygosity (OR 1.13, 95% CI: 0.76-1.67, p = 0.56) and in homozygosity (OR: 2.11, 95% CI: 0.74-6.01, p = 0.16) revealed a similar trend. Lastly, we evaluated the association between H1299R and RPL based on the number of previous miscarriages (≥2 or ≥3). This comprehensive systematic review and meta-analysis sheds light on the specific influence of the H1299R variant in the F5 gene on RPL, constituting valid support for medical care during pregnancy and genetic counseling.

“A sorrow shared …”: a qualitative content analysis of what couples with recurrent miscarriages expect from one another and their families and friends

STUDY QUESTION

When couples have to face recurrent pregnancy loss (RPL), what are the partners’ wishes and needs and what is their perception of helpful and unhelpful factors with regard to their own, their partners’ and their families’ and friends’ ways of dealing with the problem?

SUMMARY ANSWER

Women and men with repeated miscarriages want open communication about their losses, but expect a sensitive and empathetic attitude from others, not pity or trivialization.

WHAT IS KNOWN ALREADY

RPL not only causes the women affected and their partners considerable emotional distress; it also has an impact on the couples’ relationships and the way they relate to their families and friends. Studies suggest that women have a greater need than their male partners to talk about their losses and that these differences may lead to dissatisfaction and cause relational tension. In addition, men often assume a ‘mainstay’ role, supporting their partners and displaying fortitude in the face of distress. As yet, however, little research has been conducted so far on the question of what the members of couples with RPL expect from one another and from their families and friends.

STUDY DESIGN, SIZE, DURATION

The study sample consisted of 147 couples and 17 women with at least 2 miscarriages attending the special unit for RPL at the University Women’s Hospital in Heidelberg (Germany) for the first time between September 2018 and October 2020 (response rate: 82.7%). The patients were asked to participate in this combined qualitative and questionnaire study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In order to explore the wishes and needs of those affected in more detail, the free text responses obtained were examined in this study by using qualitative content analysis. Categories and subcategories were created inductively to summarize and systematize content.

MAIN RESULTS AND THE ROLE OF CHANCE

Patients affected by RPL want their partners and their families and friends to deal with the topic openly and empathically. In the partnership itself, acceptance of individual grieving modes and sharing a common goal are important factors. Men, in particular, want their partners to be optimistic in facing up to the situation. Regarding communication with family and friends, it transpired that ‘good advice’, playing the matter down, inquiries about family planning, pity and special treatment are explicitly not appreciated.

LIMITATIONS, REASONS FOR CAUTION

The sample was a convenience sample, so self-selection effects cannot be excluded. In addition, the level of education in the sample was above average. Accordingly, the sample cannot be regarded as representative. The results of the content analysis are based on the respondents’ written answers to open-ended questions in the questionnaire. Unlike qualitative interview studies, further questioning was not possible in the case of ambiguities or to request more details.

WIDER IMPLICATIONS OF THE FINDINGS

Frank and sincere communication about miscarriages and about one’s own emotions and needs should be promoted both in the partnership and among family members and friends in order to strengthen the potential of social support as a resource. Open communication about the different needs of both partners is necessary to create mutual understanding. The results show the importance not only of empathy and consideration for the couples concerned but also their desire not to be pitied. Striking a fine balance between fellow-feeling and pity may also lead to tension, and this potential dilemma should be addressed in psychosocial counselling. Overall, the study contributes to a better understanding of what couples want from their families and friends when they are attempting to come to terms with RPL and highlights potential challenges in the interaction between affected couples and their families and friends.

STUDY FUNDING/COMPETING INTEREST(S)

No funding was received for this study. None of the authors declared any conflicts of interest.

TRIAL REGISTRATION NUMBER

DRKS00014965.

A Potential Mechanism of Kidney-Tonifying Herbs Treating Unexplained Recurrent Spontaneous Abortion: Clinical Evidence From the Homogeneity of Embryo Implantation and Tumor Invasion

Background: Kidney-tonifying herbs (KTHs) are widely used to treat unexplained recurrent spontaneous abortion (URSA) based on the theory of traditional Chinese medicine (TCM). However, there is still a lack of systematic evaluation and mechanistic explanation for these treatments.

Objective: The purpose of this study was to assess the clinical efficacy, and to investigate the potential mechanisms, of KTH based on TCM for the treatment of URSA.

Methods: A systematic literature search was conducted within PubMed, Embase, China Biomedical Literature database, Web of Science (WOS), China National Knowledge Infrastructure (CNKI) database, and the Wanfang database to find articles reporting on the Chinese herbal formula based around KTH for treating URSA, which were published between January 2010 and June 2021. A full bibliometric analysis was carried out; in addition, randomized controlled trial (RCT) articles were selected for systematic evaluation and meta-analysis. The drugs with the highest frequency of KTHs were screened for meta-analysis. Finally, network analysis and molecular docking were used to study the key components and potential pathway of KTHs in the treatment of URSA.

Results: The meta-analysis included nine RCTs involving 1,054 subjects. Compared with the control groups, the clinical efficacy of TCM-based KTHs in the treatment of URSA patients significantly improved outcomes. Additionally, a component target pathway network was identified, which included 32 potential blood activating components and 113 main targets. Japonine, sopranol, lysine, and matrine were considered the most important bioactive molecules for KTHs. The key potential therapeutic pathway for URSA was a tumor-related signaling pathway. The target genes for URSA regulated by KTHs were highly similar to tumor biological processes such as the regulation of apoptotic signaling pathways, inflammatory responses, angiogenesis, and epithelial metabolic transition.

Conclusion: KTH has great potential for treating URSA. Because the maintenance of pregnancy has a high similarity with tumor invasion, the research relating to tumor mechanisms should also be followed up as it may lead to new ideas and breakthroughs for research into URSA. At the same time, embryonic and decidual cells share a high degree of cellular heterogeneity and spatial structural complexity with tumor cells, and a single cell combined with spatial omics may be the best future approach for validating KTH mechanisms.

The role of endometrial B cells in normal endometrium and benign female reproductive pathologies: a systematic review

STUDY QUESTION

What are the similarities and differences in endometrial B cells in the normal human endometrium and benign reproductive pathologies?

SUMMARY ANSWER

Endometrial B cells typically constitute <5% of total endometrial CD45+ lymphocytes, and no more than 2% of total cells in the normal endometrium, and while their relative abundance and phenotypes vary in benign gynaecological conditions, current evidence is inconsistent.

WHAT IS KNOWN ALREADY

B cells are vitally important in the mucosal immune environment and have been extensively characterized in secondary lymphoid organs and tertiary lymphoid structures (TLSs), with the associated microenvironment germinal centre. However, in the endometrium, B cells are largely overlooked, despite the crucial link between autoimmunity and reproductive pathologies and the fact that B cells are present in normal endometrium and benign female reproductive pathologies, scattered or in the form of lymphoid aggregates (LAs). A comprehensive summary of current data investigating B cells will facilitate our understanding of endometrial B cells in the endometrial mucosal immune environment.

STUDY DESIGN SIZE DURATION

This systematic review retrieved relevant studies from four databases (MEDLINE, EMBASE, Web of Science Core Collection and CINAHL) from database inception until November 2021.

PARTICIPANTS/MATERIALS SETTING METHODS

The search strategy combined the use of subject headings and relevant text words related to 'endometrium', 'B cells' and B-cell derivatives, such as 'antibody' and 'immunoglobulin'. Non-benign diseases were excluded using cancer-related free-text terms, and searches were limited to the English language and human subjects. Only peer-reviewed research papers were included. Each paper was graded as 'Good', 'Fair' or 'Poor' quality based on the NEWCASTLE-OTTAWA quality assessment scale. Only 'Good' quality papers were included.

MAIN RESULTS AND THE ROLE OF CHANCE

Twenty-seven studies met the selection criteria and were included in this review: 10 cross-sectional studies investigated B cells in the normal endometrium; and 17 case-control studies compared the characteristics of endometrial B cells in control and benign female reproductive pathologies including endometritis, endometriosis, infertility, abnormal uterine bleeding, endometrial polyps and uterine fibroids. In all studies, B cells were present in the endometrium, scattered or in the form of LAs. CD20+ B cells were more abundant in patients with endometritis, but the data were inconsistent as to whether B-cell numbers were increased in endometriosis and patients with reproductive pathologies.

LIMITATIONS REASONS FOR CAUTION

Although only 'good' quality papers were included in this systematic review, there were variations in patients' age, diagnostic criteria for different diseases and sample collection time among included studies. Additionally, a large number of the included studies only used immunohistochemistry as the identification method for endometrial B cells, which may fail to provide an accurate representation of the numbers of endometrial B cells.

WIDER IMPLICATIONS OF THE FINDINGS

Histological studies found that endometrial B cells are either scattered or surrounded by T cells in LAs: the latter structure seems to be under hormonal control throughout the menstrual cycle and resembles TLSs that have been observed in other tissues. Further characterization of endometrial B cells and LAs could offer insights to endometrial B-cell function, particularly in the context of autoimmune-associated pathologies, such as endometriosis. Additionally, clinicians should be aware of the limited value of diagnosing plasma cell infiltration using only CD138.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by Finox Biotech. The authors have no conflicts of interest to declare.

PROSPERO REGISTRATION NUMBER

This systematic review was registered in PROSPERO in January 2020 (PROSPERO ID: CRD42020152915).

External validation of a frequently used prediction model for ongoing pregnancy in couples with unexplained recurrent pregnancy loss

STUDY QUESTION

What is the predictive performance of a currently recommended prediction model in an external Dutch cohort of couples with unexplained recurrent pregnancy loss (RPL)?

SUMMARY ANSWER

The model shows poor predictive performance on a new population; it overestimates, predicts too extremely and has a poor discriminative ability.

WHAT IS KNOWN ALREADY

In 50-75% of couples with RPL, no risk factor or cause can be determined and RPL remains unexplained. Clinical management in RPL is primarily focused on providing supportive care, in which counselling on prognosis is a main pillar. A frequently used prediction model for unexplained RPL, developed by Brigham et al. in 1999, estimates the chance of a successful pregnancy based on number of previous pregnancy losses and maternal age. This prediction model has never been externally validated.

STUDY DESIGN, SIZE, DURATION

This retrospective cohort study consisted of 739 couples with unexplained RPL who visited the RPL clinic of the Leiden University Medical Centre between 2004 and 2019.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Unexplained RPL was defined as the loss of two or more pregnancies before 24 weeks, without the presence of an identifiable cause for the pregnancy losses, according to the ESHRE guideline. Obstetrical history and maternal age were noted at intake at the RPL clinic. The outcome of the first pregnancy after intake was documented. The performance of Brigham's model was evaluated through calibration and discrimination, in which the predicted pregnancy rates were compared to the observed pregnancy rates.

MAIN RESULTS AND THE ROLE OF CHANCE

The cohort included 739 women with a mean age of 33.1 years (±4.7 years) and with a median of three pregnancy losses at intake (range 2-10). The mean predicted pregnancy success rate was 9.8 percentage points higher in the Brigham model than the observed pregnancy success rate in the dataset (73.9% vs 64.0% (95% CI for the 9.8% difference 6.3-13.3%)). Calibration showed overestimation of the model and too extreme predictions, with a negative calibration intercept of -0.46 (95% CI -0.62 to -0.31) and a calibration slope of 0.42 (95% CI 0.11-0.73). The discriminative ability of the model was very low with a concordance statistic of 0.55 (95% CI 0.51-0.59). Recalibration of the Brigham model hardly improved the c-statistic (0.57; 95% CI 0.53-0.62).

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective study in which only the first pregnancy after intake was registered. There was no time frame as inclusion criterium, which is of importance in the counselling of couples with unexplained RPL. Only cases with a known pregnancy outcome were included.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first study externally validating the Brigham prognostic model that estimates the chance of a successful pregnancy in couples with unexplained RPL. The results show that the frequently used model overestimates the chances of a successful pregnancy, that predictions are too extreme on both the high and low ends and that they are not much more discriminative than random luck. There is a need for revising the prediction model to estimate the chance of a successful pregnancy in couples with unexplained RPL more accurately.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used and no competing interests were declared.

TRIAL REGISTRATION NUMBER

N/A.

Interleukin 22 Expression During the Implantation Window in the Endometrium of Women with Unexplained Recurrent Pregnancy Loss and Unexplained Infertility Compared to Healthy Parturient Individuals

We evaluated the expression of interleukin-22 (IL-22) in the endometrium of women with unexplained recurrent pregnancy loss (uRPL) and unexplained infertility (UI) compared to the women with normal pregnancies. Endometrial tissues were collected from 20 women with UI, 20 women with uRPL, and 24 healthy women as a control group. Immunohistochemical expression and gene expression of IL-22 were analyzed by immunohistochemistry (IHC) and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) methods. The controls showed lower IL-22 expression than the uRPL group (P > 0.05) using PCR. It was also found that patients with UI had lower levels of IL-22 expression compared to the uRPL group (P > 0.05). Although IL-22 expression in the endometrium of patients with UI was higher than the control group, this difference was not statistically significant (P < 0.05). IL-22 immunoreactivity was observed in the endometrial glands and stromal tissues using IHC. We found the lowest IL-22 expression in the control group and the highest in uRPL samples (P < 0.05). Our findings suggest that a significant increase in IL-22 expression in uRPL patients may affect fertility and pregnancy outcomes or even have a considerable impact on immune function deficits. Further studies on the critical function of IL-22 during pregnancy are suggested.

Exploring gender differences among couples with unexplained recurrent pregnancy loss regarding preferences for supportive care

Background

International guidelines recommend to offer supportive care during a next pregnancy to couples affected by recurrent pregnancy loss (RPL). In previous research, several options for supportive care have been identified and women’s preferences have been quantified. Although it is known that RPL impacts the mental health of both partners, male preferences for supportive care have hardly been explored.

Methods

A cross-sectional study was conducted in couples who visited a specialized RPL clinic in the Netherlands between November 2018 and December 2019. Both members of the couples received a questionnaire that quantified their preferences for supportive care in a next pregnancy and they were asked to complete this independently from each other. Preferences for each supportive care option were analysed on a group level (by gender) and on a couple level, by comparing preferences of both partners.

Results

Ninety-two questionnaires (completed by 46 couples) were analysed. The overall need for supportive care indicated on a scale from 1 to 10 was 6.8 for men and 7.9 for women (P = 0.002). Both genders preferred to regularly see the same doctor with knowledge of their obstetric history, to make a plan for the first trimester and to have frequent ultrasound examinations. A lower proportion of men preferred a doctor that shows understanding (80% of men vs. 100% of women, P = 0.004) and a doctor that informs on wellbeing (72% vs. 100%, P = ≤0.000). Fewer men preferred support from friends (48% vs. 74%, P = 0.017). Thirty-seven percent of men requested more involvement of the male partner at the outpatient clinic, compared to 70% of women (P = 0.007). In 28% of couples, partners had opposing preferences regarding peer support.

Conclusions

While both women and men affected by RPL are in need of supportive care, their preferences may differ. Current supportive care services may not entirely address the needs of men. Health care professionals should focus on both partners and development of novel supportive care programs with specific attention for men should be considered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04277-4.

Relevance of systematic anti-nuclear antibodies testing after obstetrical complications

Adverses pregnancy outcomes are commonly encountered with autoimmune disease (AID). Although anti-nuclear antibodies (ANA) are often present several years before AID diagnosis, the importance of ANA testing has not been evaluated in this context. The objective of this study was to determine if ANA discovery after obstetrical complications is associated with a diagnosis of AID and improves the prognosis of subsequent pregnancies. All patients presented at the multidisciplinary board meeting (MBM) "Thrombophilia and Pregnancy", whose ANA were discovered after an obstetrical complication, were included in a multicenter descriptive study. All patients were referred to an internal medicine consultation for diagnosis. Data were collected retrospectively by computer chart analysis and updated by phone. A total of 404 patients were included, of which 50 (12.4 %) had a diagnosis of AID related to ANA. Patients with AID had higher ANA levels (p < 0.001), with more frequent specificity (26%, versus 6.7%, p < 0.0001), and more often persistent (84% versus 30.8%, p < 0.0001) compared to patients without AID. Subsequent pregnancy outcomes were not significantly affected by ANA levels and AID diagnoses. Our study shows that the discovery of ANA after obstetrical complications may lead to an early diagnosis of AID. It makes us reconsider the systematic determination of ANA after an obstetrical event because in the case where ANA are found positive, an adapted follow-up would reduce the negative impact of ANA presence on subsequent pregnancies.

Uterine factors in recurrent pregnancy losses

Congenital and acquired uterine anomalies are associated with recurrent pregnancy loss (RPL). Relevant congenital Müllerian tract anomalies include unicornuate, bicornuate septate, and arcuate uterus. Recurrent pregnancy loss has also been associated with acquired uterine abnormalities that distort the uterine cavity such as, notably, intrauterine adhesions, polyps, and submucosal myomas. Initial evaluation of women with RPLs should include an assessment of the uterine anatomy. Even if proof of efficacy of surgical management of certain uterine anomalies is often lacking for managing RPLs, surgery should be encouraged in certain circumstances for improving subsequent pregnancy outcome. Uterine anomalies such as uterine septa, endometrial polyps, intrauterine adhesions, and submucosal myomas are the primary surgical indications for managing RPLs.

Association of Human forkhead box protein 3 (FOXP3) gene polymorphisms with idiopathic recurrent pregnancy loss among Kazakhstani women

BACKGROUND

Recurrent pregnancy loss (RPL) is major pregnancy complication, with poorly defined cause.Forkhead Box P3 (FOXP3) is a transcription factor that supports Treg activation and development and attenuates immune responses. As FOXP3 production is genetically determined, we tested the association of FOXP3 gene variants with RPL.

METHODS

A retrospective case-control study, performed between April 2019 and February 2020. Study subjects comprised 62 RPL cases and 60 control women. Genotyping of the four FOXP3 variants rs2294021 (T > C), rs2232365 (G > A), rs3761548 (C > A), and rs141704699 (C > T) was done by real-time PCR, with defined clusters. Logistic odds ratios (ORs) of RPL risk were estimated with 95% confidence interval (CI) after adjustment; statistical significance set at P < 0.05.

RESULTS

Minor allele frequency (MAF) of rs2294021 was significantly lower [P < 0.001; OR(95% CI) = 0.25(0.11-0.55)], while rs2232365 MAF was significantly higher [P = 0.045; OR(95% CI) = 1.85(1.05-3.28)] in cases, hence assigning RPL-protection and -susceptibility to these variants, respectively. Increased RPL risk was seen in rs2232365 homozygous minor allele carrying genotype [OR(95% CI) = 5.14(1.01-26.15)], while reduced RPL risk was noted in rs2294021 heterozygous [OR(95% CI) = 0.30(0.11-0.80)], and homozygous minor allele [OR(95% CI) = 0.10(0.01-0.83)] genotype carriers. Moderate linkage disequilibrium analysis was seen between the tested variants. Increased frequency of TACC, and reduced frequency of CGAC haplotypes were seen in RPL cases when compared to controls, thereby assigning RPL susceptibility and protection to these haplotypes, respectively.

CONCLUSION

These results suggest that FOXP3 variants and haplotypes are associated with idiopathic RPL, suggesting the likely contribution of Treg to RPL.

Chance of live birth: a nationwide, registry-based cohort study

STUDY QUESTION

Does the sequence of prior pregnancy events (pregnancy losses, live births, ectopic pregnancies, molar pregnancy and still birth), obstetric complications and maternal age affect chance of live birth in the next pregnancy and are prior events predictive for the outcome?

SUMMARY ANSWER

The sequence of pregnancy outcomes is significantly associated with chance of live birth; however, pregnancy history and age are insufficient to predict the outcome of an individual woman's next pregnancy.

WHAT IS KNOWN ALREADY

Adverse pregnancy outcomes decrease the chance of live birth in the next pregnancy, whereas the impact of prior live births is less clear.

STUDY DESIGN, SIZE, DURATION

Nationwide, registry-based cohort study of 1 285 230 women with a total of 2 722 441 pregnancies from 1977 to 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All women living in Denmark in the study period with at least one pregnancy in either the Danish Medical Birth Registry or the Danish National Patient Registry. Data were analysed using logistic regression with a robust covariance model to account for women with more than one pregnancy. Model discrimination and calibration were ascertained using 20% of the women in the cohort randomly selected as an internal validation set.

MAIN RESULTS AND THE ROLE OF CHANCE

Obstetric complications, still birth, ectopic pregnancies and pregnancy losses had a negative effect on the chance of live birth in the next pregnancy. Consecutive, identical pregnancy outcomes (pregnancy losses, live births or ectopic pregnancies) immediately preceding the next pregnancy had a larger impact than the total number of any outcome. Model discrimination was modest (C-index = 0.60, positive predictive value = 0.45), but the models were well calibrated.

LIMITATIONS, REASONS FOR CAUTION

While prior pregnancy outcomes and their sequence significantly influenced the chance of live birth, the discriminative abilities of the predictive models demonstrate clearly that pregnancy history and maternal age are insufficient to reliably predict the outcome of a given pregnancy.

WIDER IMPLICATIONS OF THE FINDINGS

Prior pregnancy history has a significant impact on the chance of live birth in the next pregnancy. However, the results emphasize that only taking age and number of losses into account does not predict if a pregnancy will end as a live birth or not. A better understanding of biological determinants for pregnancy outcomes is urgently needed.

STUDY FUNDING/COMPETING INTEREST(S)

The work was supported by the Novo Nordisk Foundation, Ole Kirk Foundation and Rigshospitalet's Research Foundation. The authors have no financial relationships that could appear to have influenced the work.

TRIAL REGISTRATION NUMBER

N/A.

Upregulated HMGB1 levels in maternal-fetal interface of patients with unexplained recurrent spontaneous abortion from different sources

OBJECTIVE

To investigate the expression and sources of high mobility group box 1 (HMGB1) protein in the maternal-fetal interface of patients with unexplained recurrent spontaneous abortion (URSA), and further to verify the role of HMGB1 in the etiology of URSA.

METHODS

55 women at early pregnancy with URSA and 55 women undergoing selective termination of normal early pregnancy as control were included. The abortion tissues including villi and decidua were collected. The expression of HMGB1, CD45, CK7, and vimentin in abortion tissues was detected, and the localization and sources of HMGB1 were analyzed.

RESULTS

Infiltrating immune cells and expression of HMGB1 were significantly increased in villi and decidua in URSA group compared with those in the control group. In the URSA group, HMGB1 was colocalized with the CD45-labeled immune cells, and it was more obvious in decidua than in villi; in addition, HMGB1 was colocalized with the vimentin-labeled decidual stromal cells, but not with the CK7- labeled villous epithelial cells.

CONCLUSION

High expression of HMGB1 in the maternal-fetal interface in URSA patients was actively secreted by the infiltrating immune cells, and decidual stromal cells may passively release HMGB1 during necrosis.

Higher chromosomal aberration frequency in products of conception from women older than 32 years old with diminished ovarian reserve undergoing IVF/ICSI

Infertile women with diminished ovarian reserve (DOR) confront an increased miscarriage rate in assisted reproductive technology (ART). Genetic abnormality is the most important factor. However, the effects of DOR and female age on the molecular karyotype of products of conception (POCs) remain unknown. We analyzed POCs using a single nucleotide polymorphism (SNP) microarray from women with DOR who experienced first-trimester miscarriage in IVF/ICSI cycles. The SNP microarray revealed chromosomal abnormalities in 74.6% (47/63) of POCs, including trisomy in 83.0% (39/47). Chromosomal aberrations were more frequent in women older than 32 years old with DOR than in young women aged 20-32 years old (86.7% vs. 44.4%, P = 0.001). Univariate and multivariable analyses identified advanced age as a risk factor for chromosomal aberration-related miscarriage in women with DOR, with odds ratios of 8.125 (95% CI: 2.291-28.820, P = 0.001) and 5.867 (95% CI: 1.395-24.673, P = 0.016), respectively. The results showed that older women (older than 32 years old) with DOR had a high risk of miscarrying a chromosomally aberrant embryo/fetus, regardless of basal follicle-stimulating hormone (FSH), anti-Mullerian hormone (AMH), antral follicle count (AFC) and previous reproductive history. This finding indicates a novel cut-off value of age for women with DOR related to chromosomal aberration-related miscarriage.

Anxiety and depression are risk factors for recurrent pregnancy loss: a nested case-control study

BACKGROUND

To evaluate the interaction of depression and anxiety with the development of recurrent pregnancy loss (RPL).

METHODS

A nested case-control study involving 2558 participants was conducted with data from the prospective Miscarriage Woman Cohort study between 2017 and 2019 in the province of Gansu, China. The questionnaire data, self-rating anxiety scale and self-rating depression scale were collected after each participant's first miscarriage. Information on RPL outcomes was obtained from the medical records within the subsequent 2 years. All patients diagosed RPL were recruited as cases whilst a randomly selected group of women with only one miscarriage in the past were recruited as controls. The logistic regression and the interaction effects between anxiety and depression and RPL were analysed.

RESULTS

The prevalence of anxiety (n = 325, 28.7% vs. n = 278, 19.5%) and depression symptoms (n = 550, 48.6% vs. n = 589, 41.3%) for the 1132 RPL cases were higher than 1426 non-RPL controls (P < 0.001). After adjusting for possible confounding variables, the odds ratio (OR) value, reflecting the multiplicative interaction, was 1.91 (95% CI 1.50-2.44, P < 0.001) for cases with both anxiety and depression symptoms compared with the non-RPL group. The relative excess risk of interaction value, reflecting the additive interaction between anxiety and depression to RPL was 1.15 (95% CI 0.32-4.21). Moreover, the adjusted OR for RPL cases with mild anxiety and severe depression was 2.77 (95% CI 1.07-44.14, P < 0.001), for RPL cases with severe anxiety and mild depression was 4.23 (95% CI 1.01-22.21, P < 0.001), for RPL cases with severe anxiety and moderate depression was 4.34 (95% CI 1.03-21.28, P < 0.001) and for RPL cases with severe anxiety and severe depression was 5.95 (95% CI 1.09-45.09, P < 0.05).

CONCLUSIONS

Either depression or anxiety alone could increase the risk of subsequent RPL. Anxiety and depression had a synergistic effect after the first miscarriage which increased the development of subsequent RPL disease.

Clinical practice guidelines for recurrent miscarriage in high-income countries: a systematic review

Recurrent miscarriage affects 1-2% of women of reproductive age, depending on the definition used. A systematic review was conducted to identify, appraise and describe clinical practice guidelines (CPG) published since 2000 for the investigation, management, and/or follow-up of recurrent miscarriage within high-income countries. Six major databases, eight guideline repositories and the websites of 11 professional organizations were searched to identify potentially eligible studies. The quality of eligible CPG was assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE II) Tool. A narrative synthesis was conducted to describe, compare and contrast the CPG and recommendations therein. Thirty-two CPG were included, from which 373 recommendations concerning first-trimester recurrent miscarriage were identified across four sub-categories: structure of care (42 recommendations, nine CPG), investigations (134 recommendations, 23 CPG), treatment (153 recommendations, 24 CPG), and counselling and supportive care (46 recommendations, nine CPG). Most CPG scored 'poor' on applicability (84%) and editorial independence (69%); and to a lesser extent stakeholder involvement (38%) and rigour of development (31%). Varying levels of consensus were found across CPG, with some conflicting recommendations. Greater efforts are required to improve the quality of evidence underpinning CPG, the rigour of their development and the inclusion of multi-disciplinary perspectives, including those with lived experience of recurrent miscarriage.

Immunological Risk Factors in Recurrent Pregnancy Loss: Guidelines Versus Current State of the Art

Around 1-5% of all couples experience recurrent pregnancy loss (RPL). Established risk factors include anatomical, genetic, endocrine, and hemostatic alterations. With around 50% of idiopathic cases, immunological risk factors are getting into the scientific focus, however international guidelines hardly take them into account. Within this review, the current state of immunological risk factors in RPL in international guidelines of the European Society of Reproduction and Embryology (ESHRE), American Society of Reproductive Medicine (ASRM), German/Austrian/Swiss Society of Obstetrics and Gynecology (DGGG/OEGGG/SGGG) and the Royal College of Obstetricians and Gynecologists (RCOG) are evaluated. Special attention was drawn to recommendations in the guidelines regarding diagnostic factors such as autoantibodies, natural killer cells, regulatory T cells, dendritic cells, plasma cells, and human leukocyte antigen system (HLA)-sharing as well as treatment options such as corticosteroids, intralipids, intravenous immunoglobulins, aspirin and heparin in RPL. Finally, the current state of the art focusing on both diagnostic and therapeutic options was summarized.

Definition and Multiple Factors of Recurrent Spontaneous Abortion

Recurrent spontaneous abortion (RSA) is usually defined as three or more spontaneous abortions prior to 20-28 weeks gestation. RSA affects approximately 2-5% of all women of childbearing age, and it brings tremendous psychological and psychiatric trauma to the women and also results in economic burden. The causes could be female age, anatomical and chromosomal abnormalities, genetic, endocrinological, placental anomalies, infection, smoking and alcohol consumption, psychological factor, exposure to environmental factors such as heavy metal, environment pollution, and radiation.

Is there a Role of Intravenous Immunoglobulin in Immunologic Recurrent Pregnancy Loss?

Recurrent pregnancy loss (RPL) commonly refers to three or more miscarriages that occur before 20 weeks of pregnancy. The immunological cause of RPL could be either an auto- or alloimmune-related event or both. Because of the discovery of immunological abnormalities in RPL patients in clinical practice, several immunomodulatory therapies were introduced to maintain the immune balance at the maternal-fetal interface. Intravenous immunoglobulin (IVIg) is one of the immunomodulators. In recent years, several studies have analyzed the therapeutic effect of IVIg on RPL patients with antiphospholipid syndrome (APS) or unexplained RPL. However, their results are controversial. IVIg can be used in RPL patients with APS who have previously failed in other treatments. It is recommended that IVIg infusion could be considered used before conception in RPL patients who have cellular immune abnormalities such as increased natural killer (NK) cell counts, NK cell cytotoxicity, or increased T helper (Th)1/Th2 ratio, depending on the cut-off values of each hospital. The aim of this review was to summarize the mechanisms, efficacy, pharmacokinetics, and side effects associated with passive immunization using IVIg in immunologic RPL, according to the literature published in recent years. We hope that more obstetricians will be able to understand the timing and indication of IVIg properly in immunologic RPL patients and effectively enhance pregnancy outcomes for mothers and neonates.

Quality assessment of evidence-based clinical practice guidelines for the management of pregnant women with sickle cell disease using the AGREE II instrument: a systematic review

BACKGROUND

The management of pregnant women with sickle cell disease (SCD) poses a major challenge for maternal healthcare services owing to the potential for complications associated with morbidity and mortality. Trustworthy evidence-based clinical practice guidelines (CPGs) have a major impact on the positive outcomes of appropriate healthcare. The objective of this study was to critically appraise the quality of recent CPGs for SCD in pregnant women.

METHODS

Clinical questions were identified and the relevant CPG and bibliographic databases were searched and screened for eligible CPGs. Each CPG was appraised by four independent appraisers using the AGREE II Instrument. Inter-rater analysis was conducted.

RESULTS

Four eligible CPGs were appraised: American College of Obstetricians and Gynecologists (ACOG), National Heart, Lung, and Blood Institute (NHLBI), National Institute of Health and Care Excellence (NICE), and Royal College of Obstetricians and Gynaecologists (RCOG). Among them, the overall assessments of three CPGs (NICE, RCOG, NHLBI) scored greater than 70%; these findings were consistent with the high scores in the six domains of AGREE II, including:[1] scope and purpose,[2] stakeholder involvement,[3] rigor of development,[4] clarity of presentation,[5] applicability, and [6] editorial independence domains. Domain [3] scored (90%, 73%, 71%), domain [5] (90%, 46%, 47%), and domain [6] (71%, 77%, 52%) for NICE, RCOG, and NHLBI, respectively. Overall, the clinical recommendations were not significantly different between the included CPGs.

CONCLUSIONS

Three evidence-based CPGs presented superior methodological quality. NICE demonstrated the highest quality followed by RCOG and NHLBI and all three CPGs were recommended for use in practice.

Serum ferritin level is inversely related to number of previous pregnancy losses in women with recurrent pregnancy loss

OBJECTIVE

To study whether low serum ferritin (s-ferritin) levels are associated with recurrent pregnancy loss (RPL), and whether low s-ferritin predicts the risk of another pregnancy loss or the ability to conceive.

DESIGN

Cohort study.

SETTING

Fertility clinic at a university hospital.

PATIENT(S)

Eighty-four women referred to the RPL Unit and 153 women of reproductive age with no known fertility problem. s-Ferritin levels were measured in serum samples taken before pregnancy attempt.

INTERVENTION

None.

MAIN OUTCOME MEASURE(S)

s-Ferritin levels were correlated to pregnancy history, ability to conceive, and time to conception during the first 2 years after sampling. Furthermore, s-ferritin levels were correlated to outcome of the first pregnancy after referral for RPL.

RESULT(S)

Women with RPL had lower s-ferritin than the comparison group, 39.9 μg/L versus 62.2 μg/L, and had a higher prevalence of low iron stores (s-ferritin <30 μg/L), 35.7% versus 13.7%. We found an inverse relationship between s-ferritin level and number of pregnancy losses before referral. We did not find s-ferritin level to be associated with ability to conceive or time to pregnancy in either group. Nor did s-ferritin level predict the risk of losing the first pregnancy after referral for RPL.

CONCLUSION(S)

The inverse relationship between s-ferritin levels and previous pregnancy losses suggests that low s-ferritin is associated with a more severe reproductive disturbance in women with RPL. Whether low s-ferritin is causally related to RPL and if such women could benefit from iron supplementation to achieve a live birth warrants further investigation.

Defining recurrent pregnancy loss: associated factors and prognosis in couples with two versus three or more pregnancy losses

RESEARCH QUESTION

The definition of recurrent pregnancy loss (RPL) differs internationally. The European Society of Human Reproduction and Embryology (ESHRE) defines RPL as two or more pregnancy losses. Different definitions lead, however, to different approaches to care for couples with RPL. This study aimed to determine whether the distribution of RPL-associated factors was different in couples with two versus three or more pregnancy losses. If a similar distribution were found, couples with two pregnancy losses should be eligible for the same care pathway as couples with three pregnancy losses.

DESIGN

This single-centre, retrospective cohort study investigated 383 couples included from 2012 to 2016 at the Leiden University Medical Center RPL clinic. Details on age, body mass index, smoking status, number of pregnancy losses, mean time to pregnancy loss and performed investigations were collected. The prevalence of uterine anomalies, antiphospholipid syndrome, hereditary thrombophilia, hyperhomocysteinaemia, chromosomal abnormalities and positive thyroid peroxidase antibodies were compared in couples with two versus three or more pregnancy losses.

RESULTS

No associated factor was found in 71.5% of couples with RPL. This did not differ statistically between couples with two versus three or more pregnancy losses (73.6% versus 70.6%; P = 0.569). The distribution of investigated causes did not differ between the two groups.

CONCLUSIONS

As the distribution of associated factors in couples with two versus three or more pregnancy losses is equal, couples with two pregnancy losses should be eligible for the same care pathway as couples with three. This study supports ESHRE's suggestion of including two pregnancy losses in the definition of RPL.

Antinuclear antibodies positivity is a risk factor of recurrent pregnancy loss: A meta-analysis

OBJECTIVE

Immunologic mechanisms have been proposed as part of the pathogenesis mechanisms involved in recurrent pregnancy loss (RPL). Presence of positive antinuclear antibodies (ANA) is regarded as a typical feature of autoimmunity. Many studies had tried to clarify the association of ANA with RPL, but the conclusions were controversial. The aim of this meta-analysis was to assess whether ANA was positively associated with increased RPL risk.

METHODS

We searched PubMed and Embase databases for relevant literatures on the association between ANA positivity and RPL. The odds ratios (OR) with 95% confidence intervals (95%CI) were pooled using meta-analysis, and either fixed-effect or random-effect model was used based on heterogeneity across the included studies.

RESULTS

Twenty-one studies with 5038 participants (including 2683 RPL patients and 2355 controls) met the inclusion criteria were included. The total positive rate of ANA was 22.0% (591/2683) in RPL group, and 8.3% (196/2355) in the control group. RPL patients had a significantly higher ANA positive rate than controls (OR = 2.97, 95%CI 1.91-4.64, P<0.00001; I² = 75%), and a significant association between positive ANA and unexplained RPL was also observed (OR = 3.27, 95%CI 2.01-5.31, P<0.00001; I² = 70%). ANA positivity was also significantly associated with increased risk of RPL in women without defined autoimmune diseases (OR = 2.23, 95%CI 1.40-3.55, P=0.0007). Subgroup analysis demonstrated low titers of ANA (1:40≤ANA≤1: 80) were not associated with RPL (OR = 2.44, 95%CI 0.42-14.06, P=0.32), while higher ANA titer (≥1:160) had a significant association with RPL (OR = 45.89, 95%CI 8.44-249.45, P<0.00001). A higher rate of homogenous pattern in RPL patients was observed (OR = 4.89, 95%CI 2.20-10.87, P<0.001), and no significant difference in speckled pattern or nucleolar pattern was found.

CONCLUSIONS

This study demonstrated that ANA positivity was positively associated with increased RPL risk. ANA positivity is an important risk factor for RPL which needed to be screened among women with RPL.

Clinical outcomes in chronic intervillositis of unknown etiology

INTRODUCTION

Chronic intervillositis of unknown etiology (CIUE) is a histopathological lesion of the placenta that is frequently accompanied by unfavourable pregnancy outcomes, e.g. miscarriage, fetal growth restriction (FGR) and intrauterine fetal death. Earlier described case series and cohorts have been based on diverse diagnostic criteria of CIUE. To improve our understanding of clinical outcomes associated with CIUE, we report the obstetric and perinatal outcomes in a cohort based on the recently described diagnostic criteria.

METHODS

CIUE is defined as an infiltrate occupying 5% or more of the intervillous space with approximately 80% of mononuclear cells positive for CD68 in the absence of an infection. Thirty-eight cases were included. Also previous and subsequent pregnancies were described.

RESULTS

Pregnancies accompanied by CIUE frequently resulted in FGR (51.6%) and pre-term birth (55.3%). Twenty-nine out of 38 pregnancies (76.3%) with CIUE resulted in a living baby. Women with CIUE frequently have had a miscarriage (16/38; 42%). Four-teen subsequent pregnancies in 8 women resulted in 2 miscarriages, 2 terminations of pregnancy for FGR, 1 early neonatal death and 9 living babies (9/14; 64.3%). Histopathologically confirmed CIUE recurred in 5 out of 10 subsequent pregnancies. Two pregnancies with recurrent CIUE were terminated, one pregnancy ended in a late miscarriage and another resulted in term birth complicated by FGR. Recurrent CIUE can also be accompanied by an uncomplicated pregnancy (1/5; 20%).

CONCLUSION

This study provides additional insight into the clinical phenotype of CIUE and emphasises the need for further research to understand the pathophysiology behind different pregnancy outcomes in CIUE.