Systemic Inflammation Response Index and Systemic Immune-inflammation Index for Prediction of Pregnancy Loss: a Case-control Study

The systemic inflammation response index (SIRI) and systemic immune inflammation index (SII) have recently been investigated as new prognostic markers for obstetric morbidities. However, there are few studies on their predictive role in patients with pregnancy loss. Predicting miscarriages may be useful to support and prevent selected cases.The aim of this study was to investigate the role of SIRI and SII in the prediction of pregnancy loss. A total of 800 patients were included in the retrospective case-control study at a tertiary hospital.Group 1 consisted of 200 patients who had a pregnancy loss for the first time; group 2 consisted of 200 patients with recurrent pregnancy loss; the control group consisted of 400 patients who had a healthy pregnancy. The groups were compared in terms of maternal characteristics, SIRI and SII. Receiver operating characteristic analysis was performed to determine optimal cut-off values for SIRI and SII in predicting pregnancy loss. SIRI and SII were higher in the group with recurrent pregnancy loss than in the control group (p < 0.001).SIRI was higher in the first pregnancy loss group than in the control group (p < 0.001).To predict recurrent pregnancy loss, optimal cut-off values were 1.57 (80% sensitivity, 70% specificity) and 924.12 (74% sensitivity, 57% specificity) for SIRI and SII, respectively. For first pregnancy loss prediction, the optimal cut-off value was 1.38 for SIRI, with 75% sensitivity and 60% specificity. SIRI and SII may be used as inflammatory markers to predict recurrent pregnancy loss. High SIRI values can also help to predict first pregnancy loss.

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

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

The Ratio of Peripheral Blood Natural Killer Cells is not a Solid Surrogate Immune Index in Unexplained Recurrent Miscarriage

Background

Immunotherapies targeting peripheral natural killer (pbNK) cells in unexplained recurrent miscarriage (uRM) remain controversial. We hypothesized that the change in pbNK cell count might be a result of innate immune responses rather than a cause.

Objective

To explore whether the pbNK count is significantly different in women testing positive than those testing negative for commonly studied autoimmune markers.

Methods

Peripheral blood samples were collected from 302 eligible patients with uRM for the antinuclear antibody (ANA) testing determined by the enzyme-linked immunosorbent assay (ELISA), anti-thyroid peroxidase antibody (TPO-Ab) testing and anti-thyroglobulin antibody (Tg-Ab) testing determined by the chemiluminescent immunoassay, and pbNK cell testing determined by flow cytometry. The patients were divided into two groups according to the pbNK normal range, and the comparative analysis entailed an examination of the prevalence rates of autoantibodies within the high pbNK group and the normal pbNK group, followed by a comprehensive investigation into the potential correlations between autoantibodies and pbNK cells.

Results

There was a positive association between TPO-Ab positivity and high pbNK cells (p=0.016, OR=5.097, 95% CI 1.356-19.159), while there was a negative association between ANA positivity and high pbNK cells (p=0.013, OR=0.293, 95% CI 0.111-0.773). TPO-Ab-positive patients had a higher pbNK cell count compared with TPO-Ab-negative patients, while ANA-positive patients had a lower pbNK cell count compared with ANA-negative patients.

Conclusion

The change in pbNK cell count may be a consequence of immune responses, and there should be careful consideration in applying it as an immunotherapeutic index.

Relationship Between Steroid Hormone Profile and Premenstrual Syndrome in Women Consulting for Infertility or Recurrent Miscarriage

To determine the relationships between luteal-phase steroidal hormonal profile and PMS for a large number of women attending a dedicated fertility clinic. This was a retrospective cross-sectional study on women attending a hospital-based clinic for fertility concerns and/or recurrent miscarriage. All participants were assessed with a women's health questionnaire which also included evaluation of premenstrual symptoms. Day of ovulation was identified based on the peak mucus symptom assessed by the woman after instruction in a fertility awareness-based method (FABM). This enabled reliable timing of luteal-phase serum hormone levels to be taken and analysed. Between 2011 and 2021, 894 of the 2666 women undertaking the women's health assessment had at least one evaluable serum luteal hormone test. Serum progesterone levels were up to 10 nmol/L lower for symptomatic women compared with asymptomatic women. This difference was statistically significant (p < 0.05) for the majority of PMS symptoms at ≥ 9 days after the peak mucus symptom. A similar trend was observed for oestradiol but differences were generally not statistically significant. ROC curves demonstrated that steroid levels during the luteal phase were not discriminating in identifying the presence of PMS symptoms. Blood levels for progesterone were lower throughout the luteal phase in women with PMS, with the greatest effect seen late in the luteal phase.

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

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the diagnostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in women with a history of abortion (missed and threatened) and recurrent pregnancy loss (RPL) in comparison with healthy pregnancies.

METHODS

Electronic databases including MEDLINE, Scopus, Web of Science, Embase, and Cochrane Library were searched for NLR and PLR in women who experienced early pregnancy loss up to January 1, 2023 with a combination of proper keywords. Meta-analysis was done for comparison with three or more studies and summary estimates were measured.

RESULTS

A total of 390 citations were retrieved initially, and after screening, 16 articles were deemed eligible for the final review. Among these, 14 studies underwent meta-analysis. The meta-analysis revealed that the standard mean of the NLR was significantly higher in abortion cases compared to the control group. However, there was no significant difference in the PLR between the pregnancy loss group and the control group.

CONCLUSION

NLR was significantly higher among RPL patients compared to the control group, according to these data, NLR may be capable of being used in the diagnosis of RPL as an easy, cheap, and accessible modality. Further studies, which take these variables into account, will need to be undertaken to determine the diagnostic value of NLR and PLR in early pregnancy loss.

Decreased Expression of Placental Proteins in Recurrent Pregnancy Loss: Functional Relevance and Diagnostic Value

Miscarriages affect 50-70% of all conceptions and 15-20% of clinically recognized pregnancies. Recurrent pregnancy loss (RPL, ≥2 miscarriages) affects 1-5% of recognized pregnancies. Nevertheless, our knowledge about the etiologies and pathophysiology of RPL is incomplete, and thus, reliable diagnostic/preventive tools are not yet available. Here, we aimed to define the diagnostic value of three placental proteins for RPL: human chorionic gonadotropin free beta-subunit (free-β-hCG), pregnancy-associated plasma protein-A (PAPP-A), and placental growth factor (PlGF). Blood samples were collected from women with RPL (n = 14) and controls undergoing elective termination of pregnancy (n = 30) at the time of surgery. Maternal serum protein concentrations were measured by BRAHMS KRYPTOR Analyzer. Daily multiple of median (dMoM) values were calculated for gestational age-specific normalization. To obtain classifiers, logistic regression analysis was performed, and ROC curves were calculated. There were differences in changes of maternal serum protein concentrations with advancing healthy gestation. Between 6 and 13 weeks, women with RPL had lower concentrations and dMoMs of free β-hCG, PAPP-A, and PlGF than controls. PAPP-A dMoM had the best discriminative properties (AUC = 0.880). Between 9 and 13 weeks, discriminative properties of all protein dMoMs were excellent (free β-hCG: AUC = 0.975; PAPP-A: AUC = 0.998; PlGF: AUC = 0.924). In conclusion, free-β-hCG and PAPP-A are valuable biomarkers for RPL, especially between 9 and 13 weeks. Their decreased concentrations indicate the deterioration of placental functions, while lower PlGF levels indicate problems with placental angiogenesis after 9 weeks.

Expanding the role of chromosomal microarray analysis in the evaluation of recurrent pregnancy loss

Multiple factors contribute to recurrent pregnancy loss (RPL). This review highlights the latest international guidelines for RPL workup, including immunological testing, by the American Society for Reproductive Medicine (ASRM), the European Society of Human Reproduction and Embryology (ESHRE), and the Royal College of Obstetricians and Gynaecologists (RCOG). These three societies recommend testing for antiphospholipid syndrome. ESHRE and RCOG also recommend thyroid peroxidase antibody testing, whereas ASRM does not. All guidelines advise against testing of natural killer cells, cytokines, antinuclear antibodies, human leukocyte antigen (HLA) compatibility, anti-HLA antibodies, and anti-sperm antibodies. However, when following ASRM, ESHRE or RCOG diagnostic guidelines, over 50% of cases have no identifiable cause. Genetic testing of products of conception (POC) can improve our understanding of unexplained RPL as aneuploidy is a common cause of RPL. Based on studies reporting results from chromosomal microarray analysis (CMA) of POC, we propose a novel algorithm for RPL evaluation. The algorithm involves following evidence-based societal guidelines (published by ASRM, ESHRE, or RCOG), excluding parental karyotyping, in combination with CMA testing of miscarriage tissue. When utilizing this new evaluation algorithm, the number of unexplained cases of RPL decreases from over 50% to less than 10%. As a result, most patients are provided an explanation for their loss and healthcare costs are potentially reduced. Patients with an otherwise negative workup with euploid POC, are classified as "truly unexplained RPL". These patients are excellent candidates for enrollment in randomized, controlled trials examining novel immunological testing and treatment protocols.

Massive perivillous fibrin deposition: Diagnosis, obstetrical features, and treatment

MPVFD (Massive perivillous fibrin deposition) is placental lesion characterized by extensive massive deposits of fibrin in the intervillous space, extending over at least 25 % of the placental volume. Currently, this pathology can only be detected through histopathological examination of the placenta after a pregnancy has ended. The underlying mechanisms are poorly studied, there is no biomarker available for the diagnosis of MPVFD and treatment protocols are experimental and still lacking. The objective of this study is to systematically review the literature on the associated clinicopathologic features, treatment, and prognosis of MPVFD. We ended up with 17 studies, of these 12 studies were considered relevant for this article and included in the final analysis. All studies reporting MPVFD are retrospective. MPVFD is associated with recurrent miscarriage, intra uterine fetal death (IUFD), intra uterine growth restriction (IUGR) and preterm delivery. The prevalence in pregnancies with a delivery after 22 weeks of gestation was at 1.1 % and even higher to 2.7 % in recurrent early miscarriages. The reported risk of fetal death in MPVFD ranges mainly from 15 to 80 %. Preterm delivery is spontaneous in 50 to 70 % of cases and induced by of a severe intrauterine growth restriction (IUGR) in 30 to 50 % of cases depending on the study. Its causes and treatment are still poorly understood, although several avenues have been explored. This review summarizes current understanding of the prevalence, diagnostic features, clinical consequences, immune pathology, and potential prophylaxis against recurrence in this chronic inflammatory placental syndrome.

Soluble Forms of Immune Checkpoints and Their Ligands as Potential Biomarkers in the Diagnosis of Recurrent Pregnancy Loss-A Preliminary Study

Immune checkpoints (ICPs) serve as regulatory switches on immune-competent cells. Soluble ICPs consist of fragments derived from ICP molecules typically located on cell membranes. Research has demonstrated that they perform similar functions to their membrane-bound counterparts but are directly present in the bloodstream. Effective control of the maternal immune system is vital for a successful pregnancy due to genetic differences between the mother and fetus. Abnormalities in the immune response are widely acknowledged as the primary cause of spontaneous abortions. In our research, we introduce a novel approach to understanding the immune-mediated mechanisms underlying recurrent miscarriages and explore new possibilities for diagnosing and preventing pregnancy loss. The female participants in the study were divided into three groups: RSA (recurrent spontaneous abortion), pregnant, and non-pregnant women. The analysis of soluble forms of immune checkpoints and their ligands in the serum of the study groups was conducted using the Luminex method Statistically significant differences in the concentrations of (ICPs) were observed between physiological pregnancies and the RSA group. Among patients with RSA, we noted reduced concentrations of sGalectin-9, sTIM-3, and sCD155, along with elevated concentrations of LAG-3, sCD80, and sCD86 ICPs, in comparison to physiological pregnancies. Our study indicates that sGalectin-9, TIM-3, sLAG-3, sCD80, sCD86, sVISTA, sNectin-2, and sCD155 could potentially serve as biological markers of a healthy, physiological pregnancy. These findings suggest that changes in the concentrations of soluble immune checkpoints may have the potential to act as markers for early pregnancy loss.

The metabolomic profile of endometrial receptivity in recurrent miscarriage

BACKGROUND

Endometrial receptivity has been the focus of continuous research for over eight decades; however, current clinical practice lacks an accurate test of endometrial receptivity to allow the prediction of successful pregnancy. We aimed to characterize the endometrial metabolomic profiles of women who suffered recurrent miscarriage using discovery metabolomics and to set the foundation for the development of an endometrial receptivity test.

METHODS

This was a prospective multicenter cohort study led by the Tommy's National Centre for Miscarriage Research in Birmingham. Endometrial biopsies were obtained during the window of implantation from 24 women aged 18-35 years, who were not pregnant and regularly menstruating, diagnosed with unexplained recurrent miscarriage. The metabolite composition and relative concentrations of samples were analyzed applying ultra-high performance liquid chromatography-mass spectrometry to investigate water-soluble and lipid metabolites.

RESULTS

Various metabolic perturbations are associated with observation of increased numbers of miscarriages. They relate to fatty acid metabolism including increased lipolysis and decreased medium chain fatty acid beta-oxidation, poorer mitochondrial health, and redox-active co-factors which are present at higher oxidative levels. Other metabolic perturbations are associated with observation of live birth following miscarriages. They relate to perturbed cholesterol-cholesterol sulphate metabolism, fatty acid metabolism including increased diacylglyceride lipolysis and decreased medium chain fatty acid beta-oxidation, and improved mitochondrial health.

CONCLUSIONS

The present endometrial metabolomics discovery studies have implicated a small number of metabolic pathways and biological functions which are biologically important in miscarriage mechanisms.

Future risk of metabolic syndrome after recurrent pregnancy loss: a cohort study using UK Biobank

OBJECTIVE

To evaluate the risk of metabolic syndrome (MS) after recurrent pregnancy loss (RPL) using UK Biobank data. A history of pregnancy loss is associated with the development of cardiovascular diseases in the future. However, the association between RPL and subsequent MS is poorly understood. Therefore, we aimed to check the risk of MS after RPL.

DESIGN

The study population was divided into 2 groups according to reproductive history: women with a history of RPL and women without a history of RPL. Recurrent pregnancy loss was defined as 2 or more spontaneous miscarriages, and MS was defined as at least 3 of the following: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol levels, high-blood pressure, and hyperglycemia.

SETTING

UK Biobank resource.

PATIENTS

The UK Biobank is a prospective cohort study that enrolled individuals aged between 40 and 69 years whose medical and reproductive histories were retrieved at enrollment. In this cohort, only women with a history of at least one pregnancy were selected.

INTERVENTIONS

Recurrent pregnancy loss.

MAIN OUTCOME MEASURES

The primary outcome was the prevalence of MS. The secondary outcomes were 5 diagnostic components of MS.

RESULTS

We analyzed 228,674 women, including 15,702 with a history of RPL and 212,972 without a history of RPL. Women with a history of RPL have a higher prevalence of MS between the ages of 40 and 60 years (33.0% vs. 31.5%). After adjusting for covariates (age, race, number of live births, early menopause, smoking, alcohol consumption, and physical activity), the increased risk of MS after RPL remained significant (adjusted odds ratio, 1.10; 95% confidence interval, 1.06-1.15). Furthermore, in the analysis of the 5 diagnostic components of MS, a history of RPL significantly increased the risk of abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol levels, and hyperglycemia.

CONCLUSION

Middle-aged women with a history of RPL have an increased risk of MS.

Recognition of the Subtypes Classification and Diagnostic Signature Based on RNA N6-Methyladenosine Regulators in Recurrent Spontaneous Abortion

Recurrent spontaneous abortion (RSA) is a common reproductive disease in female patients that seriously affects the quality of life of patients. N6-methyladenosine (m6A), as the most common modification, plays an important role in various biological behaviors; however, the relationship between m6A and RSA is still unknown. In the present study, we utilized RNA sequencing data and clinical information of RSA patients and normal women in the GEO database to identify the expression profiles of m6A regulators in RSA. Based on the m6A regulators' expression profiles, we constructed a random forest model consisting of 4 genes to predict the prevalence of RSA patients, including FMR1, METTL14, LRPPRC, and RBMX. The predictive performance of the nomogram was constructed and validated. Not only that, consensus clustering was performed to divide RSA patients into 3 clusters based on the expression of m6A regulators and calculated the m6A scores and immune infiltration of patients in different clusters. It was found that the TH1-type immune response was dominant in the A cluster, the B-type immune activity was poor, and the C cluster was the strongest. In addition, on the basis of m6A typing, we further used the differentially expressed genes between clusters to perform consensus clustering verification, and the results were consistent with the previous findings. In conclusion, the m6A regulators played an indispensable role in the occurrence of RSA, and the m6A-based typing could effectively identify the immune characteristics of different RSA patients to a certain extent, providing a new direction and strategy for the diagnosis and treatment of RSA patients.

Genetic causes of sporadic and recurrent miscarriage

Approximately 80% of miscarriages happen within the first 12 weeks of gestation. More than half of early losses result from genetic defects, usually presenting as abnormal chromosome numbers or gene rearrangements in the embryo. However, the impact of genetics on pregnancy loss goes well beyond embryonic aneuploidy. For example, the use of big data has recently led to the discovery of specific gene mutations that may be implicated in sporadic and recurrent miscarriages. Further, emerging data suggest that genetic factors play a role in conditions for which there is a causative association with recurrent pregnancy loss. Here, we summarize the evidence on the genetics of miscarriage and provide an overview of the diagnosis and prevention of genetic causes associated with sporadic and recurrent pregnancy loss.

We know all too well the significant psychological impact of miscarriage and recurrent miscarriage: so where is the support?

Miscarriage and recurrent miscarriage affect a significant proportion of every population with research consistently showing it results in profound and often prolonged psychological impacts. Despite the serious psychological impacts, support for miscarriage remains grossly inadequate. There are many ways to ameliorate the impact of these losses, which are not difficult, expensive, or time consuming. At a basic level, people want and need acknowledgment and validation of their grief and loss and greater information provision at the time of loss. A clear discrepancy also exists between the bereavement care offered by health care providers and the care wanted and needed by those affected, that must be addressed as a matter of urgency. At a health care system level, the collection of national miscarriage data must begin, to allow for a true understanding of the socioeconomic cost of miscarriage and the burden of early pregnancy loss on individuals, families, and our social systems. Furthermore, to direct research funding appropriately, establishing national research funding priorities for miscarriage support, as they have in the United Kingdom, is vital in assisting researchers and other key stakeholders to effectively target research in areas that are likely to have the greatest public health benefit. Consumers, health practitioners, and policymakers could achieve a lot for many with just a little commitment to change.

The prevalence of sporadic and recurrent pregnancy loss

This manuscript reports on the prevalence of early pregnancy loss. The impact of improved pregnancy diagnosis and influence of increased age and body mass index at first birth are discussed.

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

PROBLEM

Recurrent pregnancy loss (RPL) and recurrent implantation failure (RIF) represent distinct clinical conditions with established definitions, both of which have been linked to an underlying pro-inflammatory state. This study aimed to explore the levels of monocytic-myeloid-derived suppressor cells (M-MDSCs) and regulatory T cells (TReg ) in a cohort of RPL and RIF women and their potential contribution to RPL and RIF.

METHOD OF STUDY

One hundred and eight non-pregnant women were evaluated: 40 RPL, 41 RIF, and 27 fertile healthy controls (HC). A multiparametric flow cytometry approach was utilized to measure and quantify the frequency of M-MDSCs and TReg cells. Cytokine levels in plasma samples were evaluated through a multiplex assay. M-MDSCs levels were significantly higher in RPL and RIF patients compared to HC.

RESULTS

M-MDSCs levels were significantly higher in RPL (9.4% [7-11.6]) and RIF (8.1% [5.9-11.6]) patients compared to HC (6% [4.2-7.6]). An optimal cut-off of 6.1% for M-MDSCs disclosed a sensitivity of 75.6% and 89.7% and a specificity of 57.7% and 57.7% in RIF and RPL groups, respectively. A significant negative correlation was observed between M-MDSCs and TReg (p = .002, r = -.51).

CONCLUSIONS

Our preliminary data allowed us to build a predictive model that may aid as a potential diagnostic tool in the clinic. These findings could provide a better understanding of these pathologies and a better definition of patients that could benefit from personalized treatments to promote pregnancy. Additional exploration and confirmation in distinct study groups are needed to fully assess the diagnostic capabilities of this biomarker.

Series of overviews on miscarriage and recurrent miscarriage

Miscarriage is a relatively common occurrence with many knowns and unknowns and a profound psychological impact on individuals and couples. The editors felt it was time to publish a series of overviews for Views and Reviews on both sporadic miscarriage and recurrent miscarriage. The series starts with the prevalence of miscarriage and recurrent miscarriage and subsequently describes the psychological impact, what we know of the genetics, whether uterine natural killer cells may play a role, the association with infections, and potential interventions.

[Hematological workup in cases of recurrent early miscarriages: what evidences?]

Recurrent miscarriages have a major psychological and somatic impact, as well as a significant economic burden. An etiological work-up should be offered after two or three miscarriages, the threshold varying from one scientific society to another. However, the proposed biological work-up must be justified by scientific evidence. A simple blood count, basic coagulation tests including fibrinogen assay and anti-phospholipid antibodies testing should be performed initially. Hereditary thrombophilia testing should only be carried out if there is a history of maternal thrombosis. In the event of an abnormality, management should be multidisciplinary, and the prescription of medication should follow recommended guidelines. Prophylactic treatment is not justified in the absence of a known etiology.

The Clinical Significance of Embryonic Chromosomal Errors in Recurrent Pregnancy Loss: an Analysis of 1107 Miscarriages

The objective of this study was to characterize the relationship between embryonic chromosomal errors in the products of conception (POC) and maternal age, gestational age (GA) of pregnancy loss, and findings on routine recurrent pregnancy loss (RPL) workup. This is a retrospective cohort study of women with a history of ≥ 2 pregnancy losses and who underwent cytogenetic testing on the POC of a subsequent pregnancy loss at an academic tertiary RPL referral center. The association between the odds of embryonic chromosomal errors in POC and maternal age, GA of pregnancy loss, as well as RPL work up findings was investigated. A total of 1107 miscarriages were analyzed from 741 women. There was an overall linear relationship between embryonic chromosomal errors and maternal age, with a nearly twofold increase in the odds of chromosomal error with every 5-year increase in maternal age (P < 0.0001). The association between chromosomal errors and GA was also linear (P = 0.0001), with most losses having no chromosomal errors after 13 weeks' gestation. Women with ≥ 1 positive findings on routine RPL diagnostic workup had lower odds of embryonic chromosomal errors compared to those with a normal workup [OR 0.57 (95% CI = 0.41-0.80)]. Notably, the estimated prevalence of chromosomal error remained high (> 60%) in women ≥ 35 years old irrespective of findings on routine evaluation. While embryonic chromosomal errors were associated with advanced maternal age, early GA of loss, and a negative routine RPL evaluation, the prevalence of chromosomal errors remained high in all subpopulations. These findings suggest that primary cytogenetic testing on POCs should be offered at the time of second and subsequent pregnancy losses in all RPL patients.

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

Objective

To evaluate the prevalence of abnormal endocrine dysfunction for recurrent pregnancy loss (RPL) amongst patients with two versus three or more pregnancy losses.

Methods

This cross-sectional study retrospectively collected pre-pregnancy data of 537 women diagnosed with RPL in Shengjing Hospital of China Medical University from 2017 to 2022, including the baseline data of patients and the test results of endocrine factors. Several endocrine dysfunction included in this study were: thyroid dysfunction, obesity, hyperprolactinemia, polycystic ovary syndrome and blood glucose abnormality. Furthermore, vitamin D level were collected to study its relationship with endocrine dysfunction. Finally, we subdivided the patients according to the number of previous pregnancy loss and compared the prevalence of endocrine dysfunction between subgroups.

Results

Among 537 RPL patients, 278 (51.8%) patients had abnormal endocrine test results. The highest incidence of endocrine dysfunction was thyroid dysfunction (24.39%, 131/537), followed by hyperprolactinemia (17.34%, 85/490), obesity (10.8%, 58/537), polycystic ovary syndrome (10.50%, 56/533), and abnormal blood glucose (5.29%, 27/510). Only 2.47%(13/527) of patients have vitamin D level that reach the standard. After subdividing the population according to the number of pregnancy loss, we did not find that the incidence of endocrine dysfunction (P=0.813), thyroid dysfunction (P=0.905), hyperprolactinemia (P=0.265), polycystic ovary syndrome (P=0.638), blood glucose abnormality (P=0.616) and vitamin D deficiency (P=0.908) were different among patients with two versus three or more pregnancy losses. However, obesity (P=0.003) was found more frequently observed in patients with more times of pregnancy loss.

Conclusion

The prevalence of endocrine dysfunction in RPL population is high. There is no difference in the prevalence of endocrine dysfunction, except for obesity, among patients with two or more pregnancy losses, which may suggest investigations of endocrine dysfunction when patients have two pregnancy losses.

Adverse obstetric and perinatal outcomes of patients with history of recurrent miscarriage: a retrospective cohort study

OBJECTIVE

To examine the associations between a history of recurrent miscarriage (RM) and adverse obstetric and perinatal outcomes in the subsequent pregnancy that progressed beyond 24 weeks.

DESIGN

Retrospective cohort study.

SETTING

A large tertiary maternity hospital.

PATIENT(S)

All women who booked for antenatal care and delivery between January 2014 and August 2021 were recorded. The study was limited to women with a singleton pregnancy, and to avoid intraperson correlation, we selected the first record of delivery from each mother in the study, leaving 108,792 deliveries for analysis. Obstetric and perinatal outcomes were compared among 1994 women (1.83%) with a history of ≥2 miscarriages (RM), 11,477 women (10.55%) with a history of 1 miscarriage, and 95,321 women (87.62%) with no history of miscarriage, respectively.

INTERVENTION(S)

Women with a history of ≥2 miscarriages or RM.

MAIN OUTCOME MEASURE(S)

Obstetric complications included gestational diabetes mellitus, preeclampsia (subclassified as preterm and term preeclampsia), placenta previa, placenta accreta, and fetal distress. Perinatal outcomes included emergency cesarean section, elective cesarean section, induction, postpartum hemorrhage, preterm birth, stillbirth, Apgar score <7 at 5 minutes, neonatal asphyxia, neonatal sex, congenital; malformation, low birth weight, and neonatal death.

RESULT(S)

After adjusting for relevant confounders, there was an increased risk of adverse obstetric and perinatal outcomes in a subsequent pregnancy for women with a history of RM, specifically for placental dysfunction disorders: preterm preeclampsia (risk ratio [RR] = 1.58; 95% confidence interval [CI], 1.03-2.32), preterm birth (RR = 1.34; 95% CI, 1.15-1.54)], and abnormal placentation, that is placenta previa (RR = 1.78; 95% CI, 1.36-2.28), and placenta accreta (RR = 4.19; 95% CI, 2.75-6.13).

CONCLUSION(S)

Significant associations existed between a history of RM and the occurrence of adverse obstetric and perinatal outcomes including placental dysfunction disorders and abnormal placentation. These findings may contribute to the early detection and appropriate intervention for placenta-associated diseases in women with a history of RM, with the goal of avoiding or reducing the associated detrimental effects.

Identification and verification of diagnostic biomarkers in recurrent pregnancy loss via machine learning algorithm and WGCNA

Background

Recurrent pregnancy loss defined as the occurrence of two or more pregnancy losses before 20-24 weeks of gestation, is a prevalent and significant pathological condition that impacts human reproductive health. However, the underlying mechanism of RPL remains unclear. This study aimed to investigate the biomarkers and molecular mechanisms associated with RPL and explore novel treatment strategies for clinical applications.

Methods

The GEO database was utilized to retrieve the RPL gene expression profile GSE165004. This profile underwent differential expression analysis, WGCNA, functional enrichment, and subsequent analysis of RPL gene expression using LASSO regression, SVM-RFE, and RandomForest algorithms for hub gene screening. ANN model were constructed to assess the performance of hub genes in the dataset. The expression of hub genes in both the RPL and control group samples was validated using RT-qPCR. The immune cell infiltration level of RPL was assessed using CIBERSORT. Additionally, pan-cancer analysis was conducted using Sangerbox, and small-molecule drug screening was performed using CMap.

Results

A total of 352 DEGs were identified, including 198 up-regulated genes and 154 down-regulated genes. Enrichment analysis indicated that the DEGs were primarily associated with Fc gamma R-mediated phagocytosis, the Fc epsilon RI signaling pathway, and various metabolism-related pathways. The turquoise module, which showed the highest relevance to clinical symptoms based on WGCNA results, contained 104 DEGs. Three hub genes, WBP11, ACTR2, and NCSTN, were identified using machine learning algorithms. ROC curves demonstrated a strong diagnostic value when the three hub genes were combined. RT-qPCR confirmed the low expression of WBP11 and ACTR2 in RPL, whereas NCSTN exhibited high expression. The immune cell infiltration analysis results indicated an imbalance of macrophages in RPL. Meanwhile, these three hub genes exhibited aberrant expression in multiple malignancies and were associated with a poor prognosis. Furthermore, we identified several small-molecule drugs.

Conclusion

This study identifies and validates hub genes in RPL, which may lead to significant advancements in understanding the molecular mechanisms and treatment strategies for this condition.

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

OBJECTIVE

To test the hypothesis claiming an association between human papilloma virus (HPV) sperm infection and idiopathic recurrent pregnancy loss (RPL).

DESIGN

Multicenter retrospective case-control study.

SETTING

Three university hospitals.

PATIENT(S)

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.

MAIN OUTCOME MEASURE(S)

The association between HPV DNA sperm infection, as identified using polymerase chain reaction, and RPL.

RESULTS

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]).

CONCLUSIONS

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.

Identification of Single Nucleotide Polymorphisms as Biomarkers for Recurrent Pregnancy Loss in Korean Women

BACKGROUND

Single nucleotide polymorphisms (SNPs) are reportedly associated with repeated abortion. Thus, genetic analysis based on race is the key to developing accurate diagnostic tests. This study analyzed the genetic polymorphisms of recurrent pregnancy loss (RPL) patients among Korean women compared to the controls.

METHODS

In 53 women of RPL group and 50 controls, the genetic analysis was performed. The genotype distribution and allele frequency were analyzed statistically for the difference between the two groups. The association between each SNP marker and RPL risk was analyzed.

RESULTS

The genotypes of LEPR, endothelial nitric oxide synthase (eNOS), KDR, miR-27a, miR-449b, and tumor necrosis factor-alpha (TNF-α) were analyzed using odds ratio (OR) with 95% confidence intervals (CIs). Only the AG genotype of miR-449b (A>G) polymorphism showed significant association with the risk of RPL when compared to the AA genotype (OR, 2.39). The combination of GG/AG+GG/CA+AA genotypes for eNOS/miR-449b/TNF-α was associated with 7.36-fold higher risk of RPL (OR, 7.36). The GG/AG+GG combination for eNOS/miR-449b showed 2.43-fold higher risk for RPL (OR, 2.43). The combination of AG+GG/CA+AA genotypes for miR-449b/TNF-α showed a significant association with the risk of RPL (OR, 7.60). From the haplotype-based analysis, the G-G-A haplotype of eNOS/miR-449b/TNF-α and the G-A haplotype of miR-449b/TNF-α were associated with increased risk of RPL (OR, 19.31; OR, 22.08, respectively).

CONCLUSION

There is a significant association between the risk of RPL and miR-449b/TNF-α combination, and therefore, genetic analysis for specific combined genotypes can be an important screening method for RPL in Korean women.

Identification and validation of a signature based on macrophage cell marker genes to predict recurrent miscarriage by integrated analysis of single-cell and bulk RNA-sequencing

Recurrent miscarriage (RM) is a chronic, heterogeneous autoimmune disease that has serious social and personal consequences. No valid and reliable diagnostic markers or therapeutic targets for RM have been identified. Macrophages impact the innate immune system and can be used as diagnostic and prognostic markers for many diseases. We first collected 16 decidua and villi tissue samples from 5 normal patients and 3 RM patients for single-cell RNA sequencing data analysis and identified 1293 macrophage marker genes. We then screened a recurrent miscarriage cohort (GSE165004) for 186 macrophage-associated marker genes that were significantly differentially expressed between RM patients and the normal pregnancy endometrial tissues, and performed a functional enrichment analysis of differentially expressed genes. We then identified seven core genes (ACTR2, CD2AP, MBNL2, NCSTN, PUM1, RPN2, and TBC1D12) from the above differentially expressed gene group that are closely related to RM using the LASSO, Random Forest and SVM-RFE algorithms. We also used GSE26787 and our own collection of clinical specimens to further evaluate the diagnostic value of the target genes. A nomogram was constructed of the expression levels of these seven target genes to predict RM, and the ROC and calibration curves showed that our nomogram had a high diagnostic value for RM. These results suggest that ACTR2 and NCSTN may be potential targets for preventative RM treatments.

Subclinical hypothyroidism and antithyroid autoantibodies in women with subfertility or recurrent pregnancy loss: Scientific Impact Paper No. 70 June 2022: Scientific Impact Paper No. 70 June 2022

The thyroid is a gland located in the neck and is important for many processes in the body. Problems with the thyroid gland are common in women of reproductive age. It is essential to have a normal working thyroid gland in order to achieve a successful pregnancy. One of the most common problems with the thyroid is underactivity (known as hypothyroidism). An early, mild form of an underactive thyroid is called subclinical hypothyroidism. Often people with this condition do not have any symptoms. Another common problem is thyroid autoimmunity. Here, the immune system attacks the thyroid gland, sometimes leading to the development of abnormal thyroid function. This can be diagnosed by the presence of proteins in the bloodstream called antibodies. Mild thyroid problems and the presence of high levels of thyroid antibodies have been linked to miscarriage and premature birth. There is debate in medicine about whether there should be routine testing of thyroid function both in the general population and in individuals who are trying for a baby. In addition, the strategies used to manage certain thyroid problems are questioned. Discussions around testing and subsequent management particularly relate to women with a history of subfertility or repeated miscarriages. This Scientific Impact Paper provides information on thyroid testing and the management of mild thyroid problems and thyroid antibodies in women with a history of subfertility or recurrent miscarriages, using the latest evidence and guidelines. It concludes that there may be a role for treating these women with thyroxine tablets (the hormone produced by the thyroid gland) when subclinical hypothyroidism is present, and gives guidance on the cut-off levels for treatment.

Thrombophilia screening in women with recurrent first trimester miscarriage: is it time to stop testing? - a cohort study and systematic review of the literature

OBJECTIVE

There are numerous studies reporting a disproportionally high prevalence of thrombophilia in women with a history of recurrent miscarriage (RM), which has led to overdiagnosis and treatment without an improvement in clinical outcomes. The objective of our study was to assess the prevalence of inherited and acquired thrombophilia in a large cohort of women with a history of early RM using internationally agreed diagnostic criteria and inclusion parameters and compare it to the meta-analysis results of existing literature.

METHODS

DESIGN: Retrospective cohort study and systematic review of literature.

SETTING

This is a retrospective cohort study set-up in two dedicated tertiary centres for women with RM in Southwest London and Surrey. We reviewed all the available literature related to causes of RMs. We ascertained the prevalence of thrombophilia in the study population and compared it with historical and published prevalence in the general population.

PARTICIPANTS

1155 women between 2012 and 2017. All patients had three or more first trimester miscarriages and a full thrombophilia screen.

RESULTS

The overall prevalence of thrombophilia in our study population is 9.2% (106/1155) with 8.1% (94/1155) of cases positive for inherited thrombophilia, which is similar to the general population; Factor V Leiden (4.9%; 57/1155) and prothrombin gene mutation (2.9%; 34/1155) were the most common inherited thrombophilias, while only 1% (12/1155) tested positive for acquired thrombophilia. Persistent positive lupus anticoagulant (LA) was found in 0.5% (6/1155) and persistent positive anticardiolipin (ACL) antibodies with a value ≥40 U/mL was found in 0.5% (6/1155) of patients. Tests for LA/ACL were performed a minimum of 12 weeks apart thus meeting the revised Sapporo criteria for a diagnosis of antiphospholipid syndrome.

CONCLUSION

The findings of our study demonstrate that the prevalence of inherited thrombophilia is similar in women with RM to that in the general population. Similarly, the prevalence of acquired thrombophilia, using the revised Sapporo criteria, in the cohort of RMs is similar to that in the general population. Therefore, we do not recommend investigation or treatment of inherited or acquired thrombophilia in women with RM.

PROSPERO REGISTRATION NUMBER

CRD42020223554.

Noninvasive Chromosome Screening for Evaluating the Clinical Outcomes of Patients With Recurrent Pregnancy Loss or Repeated Implantation Failure

This retrospective cohort study explores whether noninvasive chromosome screening (NICS) for aneuploidy can improve the clinical outcomes of patients with recurrent pregnancy loss (RPL) or repeated implantation failure (RIF) in assisted reproductive technology. A total of 273 women with a history of RPL or RIF between 2018 and 2021 were included in this study. We collected data of all oocyte retrieval cycles and single blastocyst resuscitation transfer cycles. For the patients experiencing RPL, NICS reduced the miscarriages rate per frozen embryo transfer (FET), improved the ongoing pregnancies rate and live birth rate: 17.9% vs 42.6%, adjusted OR 0.39, 95% CI 0.16-0.95; 40.7% vs 25.0%, adjusted OR 2.00, 95% CI 1.04-3.82; 38.9% vs 20.6%, adjusted OR 2.53, 95% CI 1.28-5.02, respectively. For the patients experiencing RIF, the pregnancy rates per FET in the NICS group were significantly higher than those in the non-NICS group (46.9% vs. 28.7%, adjusted OR 2.82, 95% CI 1.20-6.66). This study demonstrated that the selection of euploid embryos through NICS can reduce the miscarriage rate of patients experiencing RPL and improve the clinical pregnancy rate of patients experiencing RIF. Our data suggested NICS could be considered as a possibly useful screening test in clinical practice.

A combination of immune cell types identified through ensemble machine learning strategy detects altered profile in recurrent pregnancy loss: a pilot study

OBJECTIVE

To compare the immunologic profiles of peripheral and menstrual blood (MB) of women who experience recurrent pregnancy loss and women without pregnancy complications.

DESIGN

Explorative case-control study. Cross-sectional assessment of flow cytometry-derived immunologic profiles.

SETTING

Academic medical center.

PATIENT(S)

Women who experienced more than 2 consecutive miscarriages.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Flow cytometry-based immune profiles of uterine and systemic immunity (recurrent pregnancy loss, n = 18; control, n = 14) assessed by machine learning classifiers in an ensemble strategy, followed by recursive feature selection.

RESULT(S)

In peripheral blood, the combination of 4 cell types (nonswitched memory B cells, CD8+ T cells, CD56bright CD16- natural killer [NKbright] cells, and CD4+ effector T cells) classified samples correctly to their respective cohort. The identified classifying cell types in peripheral blood differed from the results observed in MB, where a combination of 6 cell types (Ki67+CD8+ T cells, (Human leukocyte antigen-DR+) regulatory T cells, CD27+ B cells, NKbright cells, regulatory T cells, and CD24HiCD38Hi B cells) plus age allowed for assigning samples correctly to their respective cohort. Based on the combination of these features, the average area under the curve of a receiver operating characteristic curve and the associated accuracy were >0.8 for both sample sources.

CONCLUSION(S)

A combination of immune subsets for cohort classification allows for robust identification of immune parameters with possible diagnostic value. The noninvasive source of MB holds several opportunities to assess and monitor reproductive health.

Identification of distinct seminal plasma cytokine profiles associated with male age and lifestyle characteristics in unexplained recurrent pregnancy loss

BACKGROUND

Seminal plasma contains a wide range of cytokines, chemokines and growth factors. Part of these signalling molecules assist in inducing a state of active maternal immune tolerance towards the fetus. Disbalances in seminal plasma content may contribute to pregnancy loss. This study investigated cytokine expression profiles in seminal plasma of male partners of couples with unexplained recurrent pregnancy loss (RPL) and the association with clinical and lifestyle characteristics, including smoking, alcohol consumption and body mass index (BMI).

METHODS

In the seminal plasma of 52 men who visited a specialised RPL clinic the levels of 25 pre-selected cytokines, chemokines and growth factors were measured by Bio-Plex assay or ELISA. Two-way hierarchical cluster analysis was performed. Identified patient clusters were compared on clinical and lifestyle characteristics.

RESULTS

Two distinct cytokine expression profiles in the seminal plasma were revealed by cluster analysis. Patient cluster I showed relatively higher levels of pro-inflammatory cytokines, including IL-1α, IL-1β, IL-6, IL-8, IL-12, IL-18 and TNF-α, compared to Patient cluster II. Men belonging to Patient cluster I were significantly older and had significantly more lifestyle risk factors compared to men in Patient cluster II.

CONCLUSION

Cluster analysis suggested the existence of a less favourable pro-inflammatory cytokine expression profile, being present in part of men affected by RPL and associated with advanced male age and lifestyle risk factors. These findings may serve as a starting point for further research into underlying mechanisms and ultimately lead to novel diagnostic and therapeutic approaches for couples with RPL.

Recurrent miscarriage: evidence to accelerate action

Women who have had repeated miscarriages often have uncertainties about the cause, the likelihood of recurrence, the investigations they need, and the treatments that might help. Health-care policy makers and providers have uncertainties about the optimal ways to organise and provide care. For this Series paper, we have developed recommendations for practice from literature reviews, appraisal of guidelines, and a UK-wide consensus conference that was held in December, 2019. Caregivers should individualise care according to the clinical needs and preferences of women and their partners. We define a minimum set of investigations and treatments to be offered to couples who have had recurrent miscarriages, and urge health-care policy makers and providers to make them universally available. The essential investigations include measurements of lupus anticoagulant, anticardiolipin antibodies, thyroid function, and a transvaginal pelvic ultrasound scan. The key treatments to consider are first trimester progesterone administration, levothyroxine in women with subclinical hypothyroidism, and the combination of aspirin and heparin in women with antiphospholipid antibodies. Appropriate screening and care for mental health issues and future obstetric risks, particularly preterm birth, fetal growth restriction, and stillbirth, will need to be incorporated into the care pathway for couples with a history of recurrent miscarriage. We suggest health-care services structure care using a graded model in which women are offered online health-care advice and support, care in a nurse or midwifery-led clinic, and care in a medical consultant-led clinic, according to clinical needs.

Expression and significance of PD-1 and PD-L1 in patients with recurrent spontaneous abortion: A protocol for systematic review and meta-analysis

BACKGROUND

Recurrent spontaneous abortion (RSA) accounts for the most common complication of early pregnancy in humans. As an immune checkpoint pathway, programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) can be exploited by tumor cells to evade immuno-surveillance. Many studies have shown that the expression of PD-1/PD-L1 is involved in RSA. However, the correlation between the expression of PD-1/PD-L1 and RSA is still controversial. We conducted meta-analysis to further explore the correlation between the expression of PD-1/PD-L1 and RSA, to provide a basis for clinical prevention and treatment.

METHODS

We will search PubMed, Embase, Web of Science, Google Scholar, Chinese National Knowledge Infrastructure, Chinese VIP Information, Wanfang Database, and Chinese Biomedical Literature Database for related published studies before February 2021. Two review authors will search and assess relevant studies independently. Case control studies and cohort studies will be included. The Revman 5.3 software was applied to carry out the meta-analysis for the included literature.

RESULTS

The findings of this systematic review will be disseminated in a peer-reviewed publication and/or presented at relevant conferences.

CONCLUSION

This study will provide a new theoretical basis for the prevention and treatment of RSA.

TRIAL REGISTRATION NUMBER

DOI 10.17605/OSF.IO/CZD23.Ethics and dissemination: Formal ethical approval is not required, as the data are not individualized.

Sperm genetic abnormalities and their contribution to embryo aneuploidy & miscarriage

Sperm genetic testing has been proposed for clinical diagnosis of possible causes of male infertility. We reviewed the most remarkable publications of sperm DNA integrity and sperm aneuploidy as they relate to clinical outcomes, and the relationship between both genetic defects, and its association to embryo aneuploidy and recurrent pregnancy loss.

Squaring the circle of recurrent pregnancy loss (RPL)

The recent publication of a study into the contribution of embryo chromosomal abnormalities in recurrent pregnancy loss (RPL) affords the opportunity to revisit the hypothesis that women with an aneuploid pregnancy loss have a better chance of a successful pregnancy next time than women with a chromosomally normal loss. A previous miscarriage with an abnormal karyotype (unrelated to a parental chromosome rearrangement) should not be viewed as a marker of an increased likelihood of aneuploidy in a subsequent pregnancy; it is (counterintuitively) likely to be indicative of a reduced risk of clinical miscarriage (with a higher proportion of aneuploid products) and an excellent chance for the live birth of the next pregnancy. Each couple should be treated on their own merits and with appropriate investigations performed where indicated; caution should be advised regarding offering preimplantation genetic testing for aneuploidy (PGT-A).

Machine Learning (ML) based-method applied in recurrent pregnancy loss (RPL) patients diagnostic work-up: a potential innovation in common clinical practice

RPL is a very debated condition, in which many issues concerning definition, etiological factors to investigate or therapies to apply are still controversial. ML could help clinicians to reach an objectiveness in RPL classification and access to care. Our aim was to stratify RPL patients in different risk classes by applying an ML algorithm, through a diagnostic work-up to validate it for the appropriate prognosis and potential therapeutic approach. 734 patients were enrolled and divided into 4 risk classes, according to the numbers of miscarriages. ML method, called Support Vector Machine (SVM), was used to analyze data. Using the whole set of 43 features and the set of the most informative 18 features we obtained comparable results: respectively 81.86 ± 0.35% and 81.71 ± 0.37% Unbalanced Accuracy. Applying the same method, introducing the only features recommended by ESHRE, a correct classification was obtained only in 58.52 ± 0.58%. ML approach could provide a Support Decision System tool to stratify RPL patients and address them objectively to the proper clinical management.

Phenome-Wide Analysis of Short- and Long-Run Disease Incidence Following Recurrent Pregnancy Loss Using Data From a 39-Year Period

Background It is unclear how recurrent pregnancy loss (RPL) impacts disease risk and whether there is a difference in risk between women with or without a live birth before RPL (primary versus secondary RPL). We investigated the disease risk following RPL, and whether there was a difference between primary and secondary RPL. Methods and Results Using population-wide healthcare registries from Denmark, we identified a cohort of 1 370 896 ever-pregnant women aged 12 to 40 years between 1977 and 2016. Of this cohort, 10 691 (0.77%) fulfilled the criteria for RPL (50.0% primary RPL). Average follow-up was 15.8 years. Incidence rate ratios were calculated in a phenome-wide manner. Diagnoses related to assessment and diagnosis of RPL and those appearing later in life were separated using a mixture model. Primary RPL increased the risk of subsequent cardiovascular disorders, including atherosclerosis, cerebral infarction, heart failure, and pulmonary embolism, as well as systemic lupus erythematosus, chronic obstructive pulmonary disease, anxiety, and obsessive-compulsive disorder. Women with secondary RPL had no increased risk of cardiovascular disorders. However, we observed an increased risk of gastrointestinal disorders such as irritable bowel syndrome and intestinal malabsorption, as well as mental disorders and obstetric complications. Conclusions RPL is a risk factor for a spectrum of disorders, which is different for primary and secondary RPL. Screening following RPL explains some associations, but the remaining findings suggest that RPL influences or shares cause with cardiovascular disorders, autoimmune disorders, and mental disorders. Research into the pathophysiology of RPL and later diseases merits further investigation.

Premature expression of the decidualization marker prolactin is associated with repeated implantation failure

Repeated implantation failure (RIF) is a poorly understood reproductive pathology defined by the inability to achieve a clinical pregnancy in at least three consecutive IVF cycles. In this study, we investigated whether the onset of decidualization, marked by prolactin (PRL) expression, is associated with RIF. We performed a retrospective cohort study using endometrial biopsies from women with idiopathic subfertility, that conceived naturally during the same cycle in which the biopsy was taken (group 1; n = 15) conceived naturally within three months after the biopsy was taken (group 2; n = 20), or unsuccessfully underwent six IUI cycles and three IVF cycles with transfer of at least one high-quality embryo (group 3, RIF; n = 20). Our results demonstrated that immunohistochemical PRL-staining was present in 8/15 women from group 1 (53.3%), in 1/20 women from group 2 (5.0%), and in 11/20 women from group 3 (55.0%). Increased proliferation, analyzed by Ki67 expression, was seen in women that were pregnant during the biopsy, compared to all women combined that were not pregnant (p≤.01). In conclusion, our study demonstrates that premature expression of the decidualization marker PRL during the luteal phase is associated with RIF.

Genome Sequencing Explores Complexity of Chromosomal Abnormalities in Recurrent Miscarriage

Recurrent miscarriage (RM) affects millions of couples globally, and half of them have no demonstrated etiology. Genome sequencing (GS) is an enhanced and novel cytogenetic tool to define the contribution of chromosomal abnormalities in human diseases. In this study we evaluated its utility in RM-affected couples. We performed low-pass GS retrospectively for 1,090 RM-affected couples, all of whom had routine chromosome analysis. A customized sequencing and interpretation pipeline was developed to identify chromosomal rearrangements and deletions/duplications with confirmation by fluorescence in situ hybridization, chromosomal microarray analysis, and PCR studies. Low-pass GS yielded results in 1,077 of 1,090 couples (98.8%) and detected 127 chromosomal abnormalities in 11.7% (126/1,077) of couples; both members of one couple were identified with inversions. Of the 126 couples, 39.7% (50/126) had received former diagnostic results by karyotyping characteristic of normal human male or female karyotypes. Low-pass GS revealed additional chromosomal abnormalities in 50 (4.0%) couples, including eight with balanced translocations and 42 inversions. Follow-up studies of these couples showed a higher miscarriage/fetal-anomaly rate of 5/10 (50%) compared to 21/93 (22.6%) in couples with normal GS, resulting in a relative risk of 2.2 (95% confidence interval, 1.1 to 4.6). In these couples, this protocol significantly increased the diagnostic yield of chromosomal abnormalities per couple (11.7%) in comparison to chromosome analysis (8.0%, chi-square test p = 0.000751). In summary, low-pass GS identified underlying chromosomal aberrations in 1 in 9 RM-affected couples, enabling identification of a subgroup of couples with increased risk of subsequent miscarriage who would benefit from a personalized intervention.

Evaluating the role of paternal factors in aetiology and prognosis of recurrent pregnancy loss: study protocol for a hospital-based multicentre case-control study and cohort study (REMI III project)

INTRODUCTION

Recurrent pregnancy loss (RPL) is defined as the spontaneous demise of two or more pregnancies before the fetus reaches viability. Despite investigation of multiple known maternal risk factors, in more than 50% of couples, this condition remains unexplained. Studies focusing on paternal factors in RPL are scarce, and therefore, paternal evaluation in RPL is currently very limited. However, regarding single miscarriage, there are multiple publications suggesting a contributive role of paternal factors. In this project, we aim to identify paternal factors associated with RPL and to improve couple-specific prediction of future pregnancy outcomes by developing a prediction model containing both maternal and paternal factors.

METHODS AND ANALYSIS

In a case-control design, the relation between unexplained RPL and paternal age, lifestyle factors, sperm DNA damage and immunomodulatory factors in peripheral blood and semen will be studied. Prospectively, 135 couples with naturally conceived unexplained RPL (cases) and 135 fertile couples without a history of pregnancy loss (controls) will be included, with collection of paternal blood and semen samples and documentation of clinical and lifestyle characteristics. In addition, 600 couples from both groups will be included retrospectively. To adjust for confounders, multivariate logistic regression will be used. The predictive value of paternal and maternal factors will be studied in the total RPL cohort consisting of approximately 735 couples. The primary outcome of the cohort study is live birth within 5 years after initial visit of the clinic. Secondary outcomes are ongoing pregnancy, time interval until next pregnancy and pregnancy complications.

ETHICS AND DISSEMINATION

This project is approved by the Medical Research Ethics Committee of the Leiden University Medical Center. No risks or burden are expected from the study. The findings of this study will be disseminated via peer-reviewed publications and presentations at international conferences.

TRIAL REGISTRATION NUMBER

NL7762.

Low endometrial beta-catenin and cadherins expression patterns are predictive for primary infertility and recurrent pregnancy loss

Inadequate uterine receptivity is responsible for two-third of implanting failures. Aim of the study was to investigate the role of epithelial adherence and tight-junction molecules expressed by human endometrium in predicting womens' fertility outcome. A total of 76 consecutive women, including 24 fertile (G1), 40 primary infertile (G2), and 12 recurrent pregnancy loss (RPL, G3) women, who underwent diagnostic hysteroscopy plus endometrial biopsy between 2005 and 2016 at the Gynecology Division of Sant'Andrea Hospital, Sapienza University of Rome, in Italy, were retrospectively identified and included into the study. Endometrial biopsies were assessed for the immunohistochemical expression of beta-catenin (β-catenin), E-cadherin and K-cadherin biomarkers. Expression profiles were compared between the three groups of patients and were correlated with patients' fertility outcome. In infertile patients there was a significant lower endometrial expression of β-catenin (p = .001), E-cadherin (p = .001) and K-cadherin (p = .002), compared to the fertile ones. Furthermore, β-catenin and E-cadherin intensity gradients of expression at glandular level were found totally reversed in infertile patients. Significant lower expression levels of K-catenin (p = .016) and E-cadherin (p < .0001) at glandular level were found in RPL patients. Results showed that the low endometrial expression of β-catenin, E-cadherin and K-cadherin were associated to fertility-related problems, such as primary intertility and RPL.

Sperm DNA fragmentation and recurrent pregnancy loss: a systematic review and meta-analysis

OBJECTIVE

To investigate the rate of sperm DNA fragmentation in male partners of women with recurrent pregnancy loss and fertile control women.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

A total of 579 male partners of women with recurrent pregnancy loss and 434 male partners fertile control women.

INTERVENTION(S)

Prospective studies were identified through a Pubmed search. Recurrent pregnancy loss was defined as two or more previous pregnancy losses. Fertile control women had a history of a live birth or ongoing pregnancy.

MAIN OUTCOME MEASURE(S)

The primary outcome was the rate of sperm DNA fragmentation. The summary measures were reported as mean difference with 95% confidence interval (CI).

RESULT(S)

Fifteen prospective studies were included in a qualitative review. Pooled data from 13 studies with sufficient data for meta-analysis suggest that male partners of women with a history of recurrent pregnancy loss have a significantly higher rate of sperm DNA fragmentation compared to the partners of fertile control women: mean difference 11.91, 95% CI 4.97-18.86.

CONCLUSION(S)

These findings support an association between sperm DNA fragmentation and recurrent pregnancy loss. However, given the significant heterogeneity between studies and lack of prospective pregnancy outcome data, further large prospective studies are needed.

Second Tunisian case of Anti -Tja mediated recurrent abortions

The diagnosis and the treatment of rare phenotypes remain a problematic situation in many countries especially in Tunisia. Individuals with rare phenotype may develop clinically significant red cell antibodies directed against the high incidence Antigens they lack. A 35 years old patient was referred to our laboratory to explain a high incidence (twelve) of recurrent miscarriage during the first and second terms of pregnancy. This patient was grouped as O Rhesus: 1, -2, -3, 4, 5 K:-1. In her plasma we identified a pan-reactive anti-PP1PK antibody (anti-Tja) recognized to be responsible of spontaneous recurrent abortions. The red cell phenotype was P1 and Tja negative. More investigations concluded to the absence of auto and other allo-antibodies association. Therapeutic plasmapheresis from early stages was suggested for the future pregnancy to remove anti-public antibodies in order to maintain normal placenta functions. The Anti-Tja antibody, naturally occurring in patients with rare p phenotype, has the ability to induce recurrent spontaneous miscarriages and to cause immediate hemolytic transfusion reactions. Despite the absence of compatible donors in her family, this patient is not in an impasse situation because two donors with the same phenotype were identified when investigating a first case in 2013.

Ultrastructural markers of tissue endometrial receptivity in patients with recurrent implantation failure

The scanning electron microscopy of the endometrial surface epithelium during the 'implantation window' was performed in 119 patients with uterine factor of infertility or recurrent miscarriage due to endometrial hypoplasia. Ultramorphological picture of the surface endometrial epithelium was characterized by aplasia and hypoplasia of pinopodes (67.39%), dense cell - cell contacts (69.53%), heteromorphy of secretory cells (15.22%) in combination with atypia of microenvironment cells (50%) in patients with infertility. The asynchronous development of pinopodes (46.67%) and the absence of intercellular contacts separation during the 'implantation window' (84.44%) was observed in patients with recurrent miscarriage. The revealed disturbance determines the mechanisms of the blastocyst adhesion violation and trophoblast invasion in the different stages of implantation in patients with uterine factor of infertility and recurrent miscarriage.

Single and double endometrial scratching (ES) in infertile women with strict criteria of recurrent implantation failure (RIF)

Controversies surrounding the effect of ES on pregnancy outcome in women with RIF are mostly due to the poorly defined target population. We evaluated the effect of ES on clinical outcomes in women with strict criteria of RIF before IVF/ICSI. We also examined the effect of ES on the expression of markers of endometrial receptivity. Women with failed implantation after transfer of seven or more top quality day 3 embryos or three blastocysts underwent the scratch procedure on exact days of the cycle prior to IVF/ICSI. Results were compared to no scratch control group. Using histopathology, immunohistochemistry, and scanning electron microscopy, we also examined the effect of injury on the endometrial receptivity in a separate series of observations with double ES. Cumulative pregnancy rate was significantly higher in the study group as compared to control (54.8% vs. 29.0%; p < .05). The effect of ES on the clinical outcome was seen during fresh ET, but not on the next FET cycles. ES improves impaired endometrial receptivity by partially normalizing the expression of estrogen and progesterone receptors (ERs, PRs) and pinopodes. We concluded that in a well-defined subpopulation of infertile women with RIF, ES significantly enhances pregnancy rates. ES has a specific impact on endometrial receptivity normalizing the expression of some markers.

Decreased MUC1 in endometrium is an independent receptivity marker in recurrent implantation failure during implantation window

BACKGROUND

It is postulated that women suffered from recurrent implantation failure (RIF) have different endometrial receptivity compared to those who experienced with idiopathic recurrent miscarriage (RM). In this study, expression of common endometrial markers Leukemia inhibitor factor (LIF), mucin 1 (MUC1) and integrin β3 were studied and compared.

METHODS

Fourteen women with RIF, 25 with RM and 20 fertile controls were recruited for endometrial biopsy during implantation window on day LH +  7. Spatial and temporal expression of MUC1, LIF and Integrin β3 were compared using semi-quantitative immunohistochemistry. Association of MUC1, LIF and integrin β3 expression levels with demographic and clinical characteristics were determined.

RESULTS

MUC1 expression in both luminal and glandular epithelium in women with RIF were significantly lower than that in women with RM and fertile controls. There were no differences in LIF and Integrin β3 expression in endometrial epithelium among three groups. Decreased MUC1 expression were not significantly associated with age, BMI, gravidity, parity, cycle length, progesterone level and previous miscarriage.

CONCLUSIONS

Deceased expression of MUC1 is an independent marker for endometrial receptivity in RIF women, suggesting MUC1 may contribute to the reproductive failure in RIF women.

Declined Natural Killer Cells Emerging in Women with Unexplained Recurrent Spontaneous Abortion and Further Reducing after Medical Therapy

BACKGROUND

As focus grows on reproduction, the issue of Recurrent Spontaneous Abortion (RSA), especially for unexplained reasons (URSA), is grabbing more and more attention in gynecological immunology. We investigated the changes of peripheral lymphocyte subsets focusing on whether they had some relationship with development of URSA.

METHODS

The percentage and absolute count of lymphocyte subsets (T cells, Th cells, Ts cells, B cells, NK cells) were simultaneously evaluated by flow cytometry in URSA patients (n = 48) and healthy controls (HC, n = 22).

RESULTS

Significantly lower percentage and absolute counts of NKT cells and NK cells were observed in URSA compared to the HC. After medical therapy, an obviously increase was shown in the percentage of both T cells and B cells, whereas it presented a reduction in the percentage of NK cells.

CONCLUSIONS

The flow cytometry test in T, B, NK cells is a method available to identify URSA patients from healthy women and to provide reference guides for clinical therapy.

Methylenetetrahydrofolate Reductase Polymorphisms and Risk of Recurrent Pregnancy Loss: a Case-Control Study

The balance between coagulation and fibrinolysis is an essential part in early pregnancy. Mutations in methylenetetrahydrofolate reductase (MTHFR) gene lead to decreased activity of the enzyme and hyperhomocysteinemia, which then induces platelet aggregation by promoting endothelial oxidative damage, possibly resulting in adverse effect on maintenance of pregnancy. We investigated the role of MTHFR single nucleotide polymorphisms (SNPs), C677T and A1298C, in Korean patients with recurrent pregnancy loss (RPL). We conducted a prospective case-control study in the Korean population. Subjects included 302 women with 2 or more consecutive, unexplained, spontaneous miscarriages before 20 weeks of gestation and 315 control women without a history of recurrent miscarriages. The genotyping for C677T and A1298C polymorphisms was performed using the TaqMan assay. Continuous variables were compared using Student's t-test, and χ² test was used to evaluate differences in the genotype distributions between the RPL and the controls. The genotype distribution of both polymorphisms in the RPL group did not differ from those of the controls. For further analysis, if RPL patients were divided according to the numbers of pregnancy losses (≥ 2 and ≥ 3) neither group was significantly different compared with controls. MTHFR gene C677T and A1298C polymorphisms are not associated with idiopathic RPL in Korean women, suggesting that those may not be susceptible allelic variants or be deficient to cause RPL.