Idiopathic Recurrent Pregnancy Loss Research Articles

Maternal HLA class II alleles and haplotypes associated with altered risk of recurrent pregnancy loss: A case‐control study

AbstractProblemThis study analyzed the contribution of DRB1, DQB1, and DPB1 HLA class II alleles and resulting 3‐locus haplotypes to the overall risk of idiopathic recurrent pregnancy loss (RPL).Method of studyThe study participants included 188 Tunisian participants comprising 84 women with established diagnoses of RPL, and 104 matched multiparous females as controls. Genotyping of HLA alleles was done by PCR‐SSP.ResultsThe allelic frequencies of DPB1, DRB1, and DQB1 were consistent with Hardy‐Weinberg equilibrium among control subjects. Among class II alleles, DRB1*04:01:01 (p = .03), DRB1*08:01:01 (p = .04), and DPB1*01:01:01 (p = .04) were positively associated, whereas DPB1*04:01:01 (p = .012) and DPB1*14:01:01 (p = .006) were negatively associated with risk of RPL. The association of DRB1 and DPB1 alleles with RPL was lost after correction for multiple comparisons. The prevalence of the seven determined DQB1 alleles was not significantly different among case and control groups. Higher prevalence of DRB1*07:01:01∼ DQB1*02:01:01∼DPB1*04:01:01 (0.0417 vs. 0.000; p = .049) coupled with lower prevalence of DRB1*13:01:01∼DQB1*06:01:01∼DPB1*02:01:01 (0.0167 vs. 0.1000; p = .014) haplotypes was noted in women with RPL, thus could be considered as an RPL at‐risk and RPL‐protective haplotype, respectively.ConclusionThe study establishes weak/no contribution of class II alleles and corresponding 3‐locus haplotypes to the altered risk of RPL among Tunisian women and does not confirm previous findings on other Arab‐speaking populations of an HLA association with RPL.

The effect of moderate aerobic exercise on the composition of endometrial NK cells in women with idiopathic Recurrent Pregnancy Loss

The effect of moderate aerobic exercise on the composition of endometrial NK cells in women with idiopathic Recurrent Pregnancy Loss

The role of the HLA-complex genes in genesis of human idiopathic recurrent pregnancy loss

Aim.To study the immunogenetic prerequisites of idiopathic recurrent spontaneous pregnancy losses in humans of allo- and autoimmune genesis. Methods. PCR-SSP (polymerase chain reaction with sequence-specific primers). Results. A comprehensive analysis of the distribution and frequency of allelic variants of the HLA-DRB1, HLA-DQA1, HLA-DQB1 genes testifies to an increased risk of recurrent pregnancy losses with a total homology of 50 % or more in couples and presence of the DQ2.5 genotype in a woman. The OR indicates that the risk of idiopathic recurrent spontaneous pregnancy loss increases 2.68 times when the homology of the couples is 50 % or more for two loci (HLA-DRB1, HLA-DQA1) and 12.8 times when the homology is 50 % or more for by three loci (HLA-DRB1, HLA-DQA1, HLA-DQB1), and if the DQ2.5 genotype is present in women, this risk increases 4 times. Conclusions. HLA genotyping of married couples with a history of spontaneous pregnancy loss is important for preconceptional prevention of recurrent pregnancy losses.

Effects of NGS-based PGT-a for idiopathic recurrent pregnancy loss and implantation failure: a retrospective cohort study

To clarify the effect of next-generation sequencing (NGS)–based preimplantation genetic testing for aneuploidy (PGT-A) combined with trophectoderm (TE) biopsy on the pregnancy outcomes of idiopathic recurrent pregnancy loss (iRPL) and idiopathic recurrent implantation failure (iRIF), we conducted a retrospective cohort study of 212 iRPL couples and 66 iRIF couples who underwent PGT-A or conventional in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment. The implantation rate (IR) per transfer (64.2%), clinical pregnancy rate (CPR) per transfer (57.5%), and live birth rate (LBR) per transfer (45%) of iRPL couples of the PGT-A treatment group were significantly higher (p < 0.05) than those of the conventional IVF/ICSI group (IR per transfer,38.2%; CPR per transfer,33.3%; LBR per transfer, 28.4%), whereas the pregnancy loss rate (PLR) per transfer was similar between the two groups. These effects were also significant (p < 0.05) in iRPL couples with advanced maternal age (AMA, ≥35 years), whereas no significant differences were found in clinical outcomes between the PGT-A and conventional IVF/ICSI groups in younger iRPL couples (<35 years). The cumulative clinical outcomes of iRPL couples were comparable between the PGT-A and conventional IVF/ICSI groups. No significant differences were found in any clinical outcomes between the PGT-A and conventional IVF/ICSI groups for young or AMA couples with iRIF. In conclusion, NGS-based PGT-A involving TE biopsy may be useful for iRPL women to shorten the time to pregnancy and reduce their physical and psychological burden, especially for iRPL women with AMA; however, couples with iRIF may not benefit from PGT-A treatment. Considering the small sample size of the iRIF group, further investigations with a larger sample size are needed to verify our findings.

The number of prior pregnancy losses does not impact euploidy rates in young patients with idiopathic recurrent pregnancy loss.

Our study aimed to determine the possible factors that might impact the probability of obtaining a euploid blastocyst following intracytoplasmic sperm injection (ICSI) and preimplantation genetic testing for aneuploidy (PGT-A) procedures in idiopathic recurrent pregnancy loss (RPL) patients. This single-center retrospective cohort analysis included 180 oocyte retrieval cycles of 166 women under 35years old and those diagnosed with idiopathic RPL according to American Society of Reproductive Medicine (ASRM) guidelines. Trophectoderm biopsy and next-generation sequencing (NGS) were the techniques used. Patients were stratified by the number of previous losses (Group A: 2, Group B: 3, and Group C: > 3). Baseline and embryological characteristics showed no statistically significant differences. The euploidy rate per analyzed blastocyst was comparable within the groups (63.3%, 58.2%, and 58.5%; p = 0.477). Logistic regression analyses confirmed that only the trophectoderm scores of A and B increased the probability of obtaining a euploid embryo [OR: 1.82, 95% CI (1.120-2.956), p: 0.016]. It is concluded that there was no correlation between the number of previous losses and the chance of finding at least one euploid embryo in ICSI cycles of women younger than 35years.

Differential Sperm Proteomics Reveals the Significance of Fatty Acid Synthase and Clusterin in Idiopathic Recurrent Pregnancy Loss.

Recurrent pregnancy loss (RPL) is a pervasive health issue affecting a large number of couples globally, which leads to increased emotional and financial strain on the affected families. While female factors have been extensively studied and are well known, the contribution of male factors to RPL remains largely unknown. As high as 40% of RPL cases are unexplained, which are termed as idiopathic RPL (iRPL), necessitating the investigation of male factors. The role of spermatozoa in early embryonic development is now well established, and recent research studies have shown that oxidative stress and DNA fragmentation in sperm cells are linked to RPL. The aim of this study was to identify proteomic markers of iRPL in human spermatozoa using tandem mass spectrometry. A label-free method quantified a total of 1820 proteins, and statistical analysis identified 359 differentially expressed proteins, the majority of which were downregulated in iRPL samples (344). Bioinformatics analysis revealed that proteomic alterations were mainly associated with biological processes such as response to stress, protein folding, chromatin organization, DNA conformation change, oxidative phosphorylation, and electron transport chain. In coherence with past studies, we determined fatty acid synthase (FASN) and clusterin (CLU) to be the most potential sperm markers for iRPL and confirmed their expression changes in iRPL by western blotting. Conclusively, we believe that FASN and CLU might serve as potential markers of iRPL and suggest exploratory functional studies to identify their specific role in pregnancy loss.

P-509 Genomic characterization of couples and their embryos/fetuses with idiopathic recurrent pregnancy loss

Abstract Study question To what extent do genomic variants contribute to idiopathic recurrent pregnancy loss (RPL)? Summary answer Pathogenic uniparental disomy, copy number variations, and single nucleotide variants were identified in 18 of 83 couples and their embryos/fetuses with idiopathic RPL. What is known already RPL is defined as the loss of two or more pregnancies before 24 weeks gestation. The etiologies of RPL include antiphospholipid antibody syndrome, and anatomic, endocrinological and chromosomal abnormalities. About 50% of RPL is unexplained and is termed as idiopathic RPL. Chromosomal aberrations and genetic variants have been identified to be associated with idiopathic RPL, demonstrating that genomic factors underlie idiopathic RPL. Study design, size, duration We applied genome sequencing to study genomic variations that causing idiopathic RPL. Couples and their embryos/fetuses were collected and sequenced. Genomic variations from women and men experiencing RPL and their embryos/fetuses were analyzed to fully characterize the genomic contribution to idiopathic RPL. Participants/materials, setting, methods We recruited 83 Chinese couples with idiopathic RPL and collected 249 samples from their embryos/fetuses and peripheral blood. Genomic DNA of those samples were sequenced, and pathogenic chromosomal abnormalities and genetic variants were identified. Main results and the role of chance Generally, pathogenic variants were identified in RPL females, males and embryos/fetuses. One uniparental disomy, 9 copy number variations, and 1 homozygous and 1 de novo single nucleotide variants (SNVs) were identified pathogenic in 12 RPL embryos/fetuses. Five and three pathogenic SNVs were identified in 4 RPL females and 2 RPL males respectively. Many SNVs affect the genes involved in sexual development. In total, 18 of 83 (21.69%) couples with idiopathic RPL could be explained by genomic variation, providing information for clinical treatments. Limitations, reasons for caution The sample size is relatively small, and they are from one medical center. Wider implications of the findings Genomic variations in females, males and their embryos/fetuses can cause RPL, and identification of genetic causes will facilitate further precision intervention. Trial registration number not applicable

P-540 Improper placentation due to skewed Oct4-Cdx2 expression may be a leading factor in idiopathic recurrent pregnancy loss (RPL) cases from Assam, India.

Abstract Study question Does the differential expression of key embryonic stem cell (ESC) markers due to upstream signaling cascade(s) deregulation influence RPL pathogenesis in the studied population? Summary answer Imbalanced Oct4-Cdx2 expression linked differential ESCs polarization due to β-catenin signaling deregulation during the peri-implantation period impacts RPL pathogenesis in the studied population. What is known already RPL affects approximately 2-5% of women globally and around 7% Indian women in reproductive age group; with 50% of case etiology being unclear. Proper placentation is indispensable for establishment, continuation, and success of a pregnancy; and it depends largely on a healthy balance between apoptosis and stem cell differentiation that aids proper trophoblast invasion. These differentiation events are tightly controlled by the interplay of oxygen tension, hormones, growth factors, other signaling molecules and most importantly by transcription factors including those deciding the stem cell lineage like Oct4, NANOG, and Cdx2, wherein, β-catenin is known to enhance Oct-4 activity in ESCs. Study design, size, duration The sample size was predicted using Raosoft software utilizing the prevalence rate of RPL. Overall 87 women with 2 or more pregnancy losses before completion of 20 weeks of gestation were enrolled as RPL cases with informed consent, whereas, for the control group, 107 women volunteers undergoing medical termination of pregnancy (MTP) were enrolled as gestation-week-matched comparative study group for experimental data analysis. Participants/materials, setting, methods Products of conception (POC) was collected from the MTP and RPL cases. POCs were collected in 2vials for every subject: (i) 4% buffered formalin for fixation and preparation of microscopic slides for immunofluorescence (IF) based protein expression of Oct4 and Cdx2; (ii) RNA later solution for site specific transcriptional analysis of Oct4, NANOG, Cdx2, and β-catenin utilizing Realtime PCR. The difference in expression was analyzed using SPSS statistical software. Main results and the role of chance IF based site specific protein expression data confirmed higher expression of OCT4 in RPL cases compared to MTP controls, whereas CDX2 expression was found to be low in RPL compared to MTP subjects. The Realtime PCR amplification of cDNA using β-actin as internal normalization control for Oct4 (25.76 ± 10.17 folds) and NANOG (18.32 ± 6.67folds) showed increased expression whereas the Cdx2 expression was downregulated (0.487 ± 0.186 folds) in RPL cases compared to MTP controls, indicating a shift towards pluripotency which is a non-favorable environment for the ongoing pregnancy since cell polarization for initiation of differentiation to different cell lineages is required at that time of gestation. The cdx2 and oct4 expression correlated inversely and significantly {Pearson’s correlation= −0.838, p = 0.009; Spearman’s rho= −0.786; p = 0.016}. The realtime PCR amplification of β-catenin, the key molecule involved in direct enhancing of Oct4 expression during gestation was found to be increased in RPL cases compared to MTP controls. Statistically, the β-catenin-Oct4 expression correlated positively significantly. Limitations, reasons for caution Being a patient based study, the present study is limited to being an associative study only; and therefore secondary validation of the data for causal association using cell lines or suitable model system futuristically may add valuable scientific inputs and aid clinical intervention modalities for controlling RPL. Wider implications of the findings As the majority of RPL pathogenesis etiology is undefined limiting the possibilities of clinical interventions therefore we presume the present data can layout possible therapeutic interventions by regulating key regulators influencing skewed ESC profile aiding proper placentation leading to successful pregnancy in a subpopulation of cases with RPL history. Trial registration number Not applicable

O-146 Oocyte donation does not increase live birth rates in young women suffering from recurrent pregnancy loss

Abstract Study question Does oocyte donation improve reproductive outcomes in recurrent pregnancy loss (RPL) patients? Summary answer Oocyte donation increases live birth and reduces miscarriage rates in RPL women older than 35, but it does not improve reproductive outcomes in younger patients. What is known already Recurrent pregnancy loss (RPL) is defined as 2 or more pregnancy losses prior to 20-24 weeks of gestation and has an incidence of approximately 1 to 2% in couples trying to conceive. Known risk factors for RPL are embryo aneuploidy, advanced maternal age (AMA), previous miscarriages, uterine abnormalities, parental chromosomal abnormalities, antiphospholipid syndrome, endocrine factors, such as thyroid function or obesity, and thrombophilia. However, 50-70% of patients suffering from RPL do not present any known risk factor, making the management of idiopathic RPL patients particularly challenging for ART clinicians. Study design, size, duration This is a cohort retrospective study involving 2 centers. Charts from 18,273 women undergoing IVF treatment between 2011 and 2020 were reviewed. A total of 912 patients (5%) met the definition of RPL and were classified into study groups based on their age and oocyte origin: ≤35 years old receiving oocyte donation (n = 39) or using their own oocytes (n = 35), and AMA women using donor eggs (n = 716) or their own (n = 122). Participants/materials, setting, methods Demographic variables analysed included known risk factors, number of transferred embryos, day of embryo transfer (3 vs 5) and sperm origin (partner/donor). Differences in biochemical, clinical, ongoing pregnancy, miscarriage and live birth rates were assessed by Pearson’s Chi-squared or Fisher’s exact test. P-values &amp;lt;0.05 were considered significant. Main results and the role of chance RPL patients had 2.77±1.27 pregnancy losses overall (2.76±1.37 in women ≤35 and 2.77±1.26 in patients &amp;gt;35). Most RPL patients (91.9%) were of AMA. Other RPL-associated risk factors, including uterine malformations, previous pregnancy losses, chromosomal abnormalities and thrombophilia were identified in 207/912 patients (22.7%). Interestingly, these were more frequent in patients &amp;lt;35 (37.8% vs 21%, p = 0.001). Young RPL women presented higher rates of karyotype abnormalities than older patients (17.6% vs 3.8%, p &amp;lt; 1x10-04), while showing a similar incidence of uterine abnormalities (14.9% vs 12.9%, p &amp;gt; 0.63) and thrombophilia (4.1% vs 4.7%, p &amp;gt; 0.81). RPL patients &amp;gt;35 preferentially underwent oocyte donation (85.4% vs 52.7%, p &amp;lt; 1x10-04), which led to significantly higher biochemical (52.5% vs 17.1%, p &amp;lt; 1x10-04), clinical (42.4% vs. 8.5% p &amp;lt; 1x10-04), ongoing pregnancy (37.9% vs 5.1%, p &amp;lt; 1x10-04), live birth (32% vs 4%, p &amp;lt; 1x10-04) and lower miscarriage rates (10.5% vs 40%, p = 0.0186) than in autologous cycles. In contrast, RPL patients &amp;lt;35 had similar reproductive outcomes: biochemical (41% vs. 52.9), clinical (28.2% vs. 37.1%), ongoing pregnancy (25.6% vs 29.4%), live birth (25.6% vs 26.4%) and miscarriage rates (9% vs 23%), regardless of oocyte origin (donated vs own, p &amp;gt; 0.05 for all cases). Importantly, this was also true for a small subgroup of idiopathic young RPL patients (n = 13). Limitations, reasons for caution The main limitation of this study is its retrospective nature, which does not allow for full elucidation of all potential confounders. The number of young RPL patients undergoing oocyte donation may be too low to draw significant conclusions. Wider implications of the findings RPL can be resolved in AMA patients by using donor oocytes, which points to key roles of oocyte quality and aneuploidy underlying RPL aetiology. However, RPL is not ameliorated by oocyte donation in young women, suggesting an endometrial/systemic origin and highlighting the need to further study mechanisms driving this disorder. Trial registration number Not applicable

The effect of MicroRNAs variants on idiopathic recurrent pregnancy loss.

Although the importance of miRNA variants in female reproductive disorders has been frequently reported, the association between miRNA polymorphisms and recurrent pregnancy loss (RPL) has been poorly studied. In this study, we aimed to assess the correlation of four different miRNA variants to unexplained RPL. The prevalence of four SNPs including miR-21 rs1292037, miR-155-5p rs767649, miR-218-2 rs11134527, and miR-605 rs2043556 in 280 cases with iRPL and 280 controls was performed. The DNA was extracted from all subjects and the SNPs were genotyped using RFLP-PCR methods. The data revealed that rs1292037 and rs767649 were significantly associated with higher rates of iRPL in patients compared with controls while rs11134527 and rs2043556 showed no association with increased rates of iRPL among patients. The haplotypes T-A-G-G and T-A-G-A were the most frequent in both cases and controls. Three haplotypes including T-T-G-A, C-T-G-G, and T-A-A-A showed significantly different frequencies in patients in comparison to healthy females. This study suggests that rs1292037 and rs767649 could be risk factors for increased rates of iRPL.

Idiopathic Recurrent Pregnancy Loss related toGPIagenein Iraqi patient women

Background: Recurrent pregnancy loss (RPL) is a major concern in the field of reproductive medicine. In particular, idiopathic recurrent pregnancy loss (iRPL) is a condition in which recurrent pregnancy loss occurs without a known cause. Recent studies have shown that genetic factors may contribute to iRPL, and the presence of the 807C/T silent polymorphisms in the GPIa gene has been associated with a higher risk of thrombosis and recurrent abortion.Aim: to determine the allelic frequency of GPIa 807C/T in patients with iRPL and healthy controls in Iraq.Material and Method: A T-ARMS PCR-based method was used to analyze the allelic frequency of GPIa 807C/T in 25 patients with iRPL and 25 healthy controls. The genotypic and allelic frequencies were calculated, and a statistical analysis was performed.Result: The results of this study showed that the allelic frequency for 807C was 48% and 46% in the patient and control groups, respectively. The allelic frequency of 807T was recorded as 52% in the patient group, whereas the control group showed 54%. The patient group's genotypic frequencies were distributed as 16% for 807TT, 12% for 807CC, and 72% for 807CT. On the other hand, the control group reported genotypic frequencies of 32% for 807TT, 24% for 807CC, and 44% for 807CT. Interestingly, the TC heterozygous genotype of the GPIa gene's 807C\T showed a significant increase (P ≤ 0.05) with a risk (OR=3.27) in the patient group against the control.Conclusion: the results of this study suggest that the presence of the GPIa 807C/T polymorphism is associated with a higher risk of iRPL in Iraqi patient women. The findings of this study could be used to develop new diagnostic and therapeutic strategies for iRPL.

KISS1 Gene Variations and Susceptibility to Idiopathic Recurrent Pregnancy Loss.

It is widely accepted that kisspeptin plays an integral role in the regulation of reproduction. Genetic variations in the KISS1 gene have been frequently reported to be linked to reproductive diseases, but there is still a lack of data on the association between KISS1 variations and female reproductive disorders. The present study aimed to examine the association of three missense SNPs in the KISS1 gene including rs12998, rs35431622, and rs4889 in association with idiopathic recurrent pregnancy loss (iRPL). A total of 720 individuals were recruited in this study. The DNA from the blood sample was extracted and genotyped using the PCR method. Haplotype and linkage disequilibrium (LD) have also been analyzed. The results of this study suggested that rs12998 G > A and rs4889 C > G had a significant association with iRPL (p < 0.05); while rs35431622 A > G didn't indicate any association with iRPL. A significant association was also found for three haplotypes including C-A-A, G-G-G, and G-G-A in this population. The analysis also showed a significant LD between rs12998 and rs35431622 (P < 0.0005). The rs12998 G > A and rs4889 C > G variants of KISS1 are linked to unexplained recurrent pregnancy loss and may be risk factors for this disease.

Male Contributory Factors in Recurrent Pregnancy Loss.

With 40% of idiopathic cases, recurrent pregnancy loss (RPL) is a problem of great concern for patients and clinicians. In addition to financial burden, it causes a lot of frustration and anxiety in affected couples. The primary objective of this review was to gain knowledge of recent advances in the field of recurrent pregnancy losses and to understand the role of male contributory factors in idiopathic cases. For a long time, researchers and clinicians were seeking an explanation for idiopathic RPL (iRPL) in females only; however, with recent advances in reproductive biology, the role of spermatozoa in early embryonic development has caught the attention of researchers. Clinically, only routine semen parameters and karyotyping are investigated in iRPL male partners, which seem to be insufficient in the present scenario, and thus, more information at the molecular level is required for a comprehensive understanding of iRPL. In concluding remarks, we suggest targeted multi-omics investigations in a large cohort to improve our understanding of the role of male contributory factors in iRPL.

Celiac Disease Predisposition and Genital Tract Microbiota in Women Affected by Recurrent Pregnancy Loss

The incidence of Idiopathic Recurrent Pregnancy Loss (RPL) is doubled in patients suffering from Celiac Disease (CD) compared to healthy populations. CD genetic components are HLA class II genes known as HLA-DQ2 and DQ8. Genetically susceptible women can remain asymptomatic even though they are exposed to a doubled risk of RPL compared to the general population. Furthermore, CD has been associated with microbiota alterations. The aim of this study is to evaluate endometrial and vaginal microbiota in HLA-DQ2/DQ8 positive and negative RPL patients compared to healthy pregnant women. Endometrial and vaginal microbiota of 3 subgroups were evaluated: 15 HLA-DQ2/DQ8 positive RPL women, 25 HLA DQ2/DQ8 negative RPL women (for a total of 40 RPL women) and 7 healthy fertile controls with previous uncomplicated pregnancies (all HLA-DQ2/DQ8 negative). The 2 RPL subgroups (HLA-DQ2/DQ8 positive and negative) showed a different endometrial and vaginal composition in the Lactobacillacae family compared to controls: Lactobacillus acidophilus was absent both in the vaginal and endometrial samples of RPL women, while Lactobaciluus iners, which can favor a less stable vaginal microbiota, was found only in RPL women (26.4% in HLA DQ2/DQ8 positive and 22.1% HLA DQ2/DQ8 negative) in both the vaginal and endometrial districts. In conclusion, both HLA DQ2/DQ8 positive-RPL and HLA DQ2/DQ8 negative-RPL women showed different endometrial and vaginal microbiota composition compared to healthy controls.

Whole genome bisulfite sequencing of sperm reveals differentially methylated regions in male partners of idiopathic recurrent pregnancy loss cases

To study the genome wide alterations in sperm DNA methylation in male partners of idiopathic recurrent pregnancy loss cases and note regions as potential diagnostic markers DESIGN: Case-Control study and methylome analysis of human sperm SUBJECTS: Control group consists of apparently healthy fertile men having fathered a child within the last 2 years (n = 39); and Case group consists of male partners of idiopathic recurrent pregnancy loss cases having two or more consecutive 1st trimester pregnancy losses (n = 47). None MAIN OUTCOME MEASURES: Sperm DNA samples of controls and cases were selected for Whole Genome Bisulfite Sequencing analysis based on the previously set thresholds of global methylation levels and methylation levels of imprinted genes (KvDMR and ZAC). Whole Genome Bisulfite Sequencing of selected sperm genomic DNA was performed to identify differentially methylated CpG sites of idiopathic recurrent pregnancy loss cases compared to fertile controls. Pathway analysis of all the differentially methylated genes was done by DAVID functional annotation tool and Kyoto Encyclopedia of Genes and Genomes tool. Differentially methylated CpGs within genes relevant to embryo and placenta development were selected to further validate their methylation levels in study population by pyrosequencing. A total of 9497 differentially methylated CpGs with highest enrichment in intronic regions were obtained. 5352 differentially methylated regions and 2087 differentially methylated genes were noted. Signaling pathways involved in development were enriched upon pathway analysis. Select CpGs within genes PPARG, KCNQ1, SETD2 and MAP3K4 showed distinct hypomethylated sub-populations within idiopathic recurrent pregnancy loss study population. Our study highlights the altered methylation landscape of idiopathic recurrent pregnancy loss sperm and their possible implications in pathways of embryo and placental development. The CpG sites that are hypomethylated specifically in sperm of idiopathic recurrent pregnancy loss sub-population can be further assessed as predictive biomarkers.

Sperm human papillomavirus infection and risk of idiopathic recurrent pregnancy loss: insights from a multicenter case–control study

To test the hypothesis claiming an association between human papilloma virus (HPV) sperm infection and idiopathic recurrent pregnancy loss (RPL). Multicenter retrospective case-control study. Three university hospitals. Cases included men belonging to couples affected by first trimester idiopathic RPL. Controls included men belonging to couples with proven fertility and no history of pregnancy loss; RPL was defined as the previous loss of 2 or more pregnancies. Couples were defined as "fertile" if they achieved a full-term pregnancy within the year before enrollment in the study. All participants conceived without assistance. The association between HPV DNA sperm infection, as identified using polymerase chain reaction, and RPL. The HPV DNA sperm infection was detected in 23 of 117 cases (20%; 95% confidence interval [CI]: 13%, 28%) and in 3 of 84 controls (4%; 95% CI; 1%, 10%) (P<.001). A comparison across baseline characteristics and multiple regression analysis did not identify any potentially confounding factors. Multivariate regression models showed a significant association between HPV DNA sperm infection and RPL (adjusted odds ratio, 7.44; 95% CI: 2.08, 26.58; P=.002 [Model 1]; adjusted odds ratio, 8.96; 95% CI: 2.41, 33.44; P=.001 [Model 2]). The prevalence of HPV sperm infection was significantly higher in couples affected by RPL than in their fertile counterparts. Notably, the semen sample was infected by HPV in approximately 1 out of 5 patients.

Association of B Cells with Idiopathic Recurrent Pregnancy Loss: A Systematic Review and Meta-Analysis.

Recurrent pregnancy loss (RPL) affects 1-2% of women and is defined as having experienced two or more failed pregnancies. In almost 50% of cases, the causes are idiopathic (IRPL), but increasing evidence has suggested an immunological cause. B cells are known to provide crucial support for a successful pregnancy outcome. However, their involvement in the mechanisms underlying IRPL is still unclear. This systematic review and meta-analysis aimed to comprehensively summarise the existing evidence regarding the levels and profiles of B cells in IRPL. An extensive computerized search in PubMed/Medline, Embase, Scopus, and Web of Science databases was performed with no imposed limits. Two reviewers independently screened all retrieved studies, extracted all the data, and assessed the methodological quality. Disagreements were resolved by a third reviewer. From a total of 1125 retrieved studies, 19 studies were included in the systematic review, and 8 studies were quantitatively analysed. We highlight a potential association between women with IRPL and increased levels of endometrial B cells. In addition, the flow cytometry technique seems to be preferred over immunohistochemistry for identifying those differences, while further studies are necessary to clarify the role of B cells as an immunological risk factor for RPL.

Association of Polymorphisms in the Long Non-Coding RNA HOTAIR with Recurrent Pregnancy Loss in a Korean Population.

Recurrent pregnancy loss (RPL) affects 1% to 5% of women, with devastating effects on both reproductive health and psychological well-being. Homeobox (HOX) transcript antisense RNA (HOTAIR) is a long non-coding RNA (lncRNA) produced by HOXC; it plays a major role in invasion and development of ovarian and other cancers. The aim of the present study was to analyze effects of HOTAIR polymorphisms (rs4759314 A>G, rs920778 T>C, rs1899663 G>T, and rs7958904 G>C) on RPL in Korean women. A total of 403 women with RPL and 383 healthy women were selected for this study. Genotyping analysis was performed with the polymerase chain reaction, restriction fragment length polymorphism, and the TaqMan genotyping assay. Clinical characteristics were compared using Student's unpaired t-test and the chi-square test for categorical variables. Logistic regression was performed to evaluate associations between single nucleotide polymorphisms and RPL incidence. In all assays, p < 0.05 was considered significant. HOTAIR polymorphisms rs4759314A>G and rs920778T>C were highly associated with increased risk of RPL, specifically the haplotypes rs4759314A>G/rs1899663G>T (G-T) and rs4759314A>G/rs920778 T>C (G-C). These associations were maintained in haplotypes that contained three polymorphisms (rs4759314 A>G, rs920778 T>C, and rs1899663 G>T) A-C-G, G-T-G, and G-T-T, further indicating that the HOTAIR rs4759314 and rs920778 polymorphisms play significant roles in idiopathic RPL in Korean women.

Investigation of the role of X chromosome inactivation and androgen receptor CAG repeat polymorphisms in patients with recurrent pregnancy loss: a prospective case–control study

BackgroundPrevious research has revealed that skewed X chromosome inactivation (SXCI) and androgen receptor (AR) CAG polymorphisms are associated with increased risk of recurrent pregnancy loss (RPL); however, the results are conflicting, and the underlying mechanisms remain unclear. This study investigated the role of SXCI and AR CAG polymorphisms in patients with RPL and explored whether the underlying mechanisms were related to the ovarian reserve and preimplantation embryo aneuploidy.MethodsThis was a prospective case-control study carried out in a tertiary hospital-based reproductive medicine center. An external validation RPL cohort was recruited during the study period. Data on baseline and cycle characteristics were collected. X-chromosome inactivation (XCI) was measured using a human AR assay. AR polymorphisms were assessed using quantitative fluorescent polymerase chain reactions and direct sequencing. Blastocysts of the patients with RPL were tested by single nucleotide polymorphism microarray based preimplantation genetic testing for aneuploidy.ResultsIn total, 131 patients with idiopathic RPL and 126 controls were included for the case-control study. Patients with RPL exhibited a significantly more skewed XCI distribution pattern (67.71 ± 10.50 vs. 64.22 ± 10.62, p = 0.011), as well as significantly shorter bi-allelic mean (18.56 ± 1.97 vs. 19.34 ± 2.38, p = 0.005) and X-weighted bi-allelic mean (18.46 ± 2.02 vs. 19.38 ± 2.53, p = 0.001) of AR CAG repeats. Multivariate logistic regression models indicated that CAG repeat < 20, SXCI, and duration of stimulation were independently associated with the risk of RPL. However, SXCI and AR CAG polymorphisms were not associated with ovarian reserve or preimplantation embryo aneuploidy in the RPL group, and the same results were attained in a separate validation cohort of 363 patients with RPL.ConclusionSXCI and AR CAG polymorphisms are related to RPL; however, these two factors do not lead to RPL by affecting the ovarian reserve or increasing embryo aneuploidy. The roles of SXCI and AR CAG in RPL may involve other mechanisms that require further investigation.Trial registration:NCT02504281, https://www.clinicaltrials.gov (Date of registration, 21/07/2015; date of enrolment of the first subject, 30/07/2015).

ALTERATIONS OF X-CHROMOSOME INACTIVATION (XCI) IN PREDISPOSITION TO RECURRENT PREGNANCY LOSS (RPL): A TRANSCRIPT LEVEL STUDY IN THE NORTHEAST INDIAN POPULATION

Recurrent pregnancy loss (RPL) affects 1-5% of reproductive age women, with a prevalence of 7.46% in the Indian population. Although the role of genetic modifications of the X-chromosome has been associated with idiopathic RPL in some populations, no such study is available in the Indian context. This study, therefore, aims to elucidate the role of alterations in the transcript levels of genes associated with X-chromosome inactivation (XCI) as a cause for predisposition to RPL.