Calcineurin inhibitors in the management of recurrent miscarriage and recurrent implantation failure: Systematic review and meta-analysis.

Recurrent miscarriage (RM) affects up to 2.5% of couples of reproductive age. Up to 10% of couples using assisted reproductive technology experience recurrent implantation failure (RIF). Immunosuppressive drugs, such as calcineurin inhibitors (CNIs), has been proposed for RM and RIF management. This systematic review and meta-analysis (SRMA) aimed to evaluate the efficacy and safety of CNIs in RM and RIF treatment. We searched in the three databases. Review Manager 5.4.1 was used for statistical analysis. This review included 8 studies involving 1042 women (485 women in the CNIs group and 557 women in the control group). CNI treatment (cyclosporine [CsA] and tacrolimus [TAC]) increases live birth rate (LBR, odds ratio [OR]: 2.52; 95% confidence interval [CI]: 1.93-3.28, p < 0.00001) and clinical pregnancy rate (OR: 2.25; 95% CI: 1.54-4.40, p < 0.0001) and decreases miscarriage rate (OR: 0.45 95% CI: 0.32-0.63, p < 0.00001) when compared to the control. Side effects and obstetric and neonatal complications was similar in both groups. In conclusion, CNIs increased LBR in women with RM and RIF but there is a moderate risk of bias. Subgroup analysis revealed that CNIs improved LBR in women with RM with a low risk of bias. However, in women with RIF, with moderate to high risk of bias. The use of CsA and TAC, in low doses and for a short period, for managing reproductive failures in women seems to be safe, not causing serious side effects nor increasing the risk of obstetric and neonatal complications.

The use of immunotherapies for recurrent miscarriage: An overview of systematic reviews and meta-analysis.

Immunotherapies have been a treatment proposed for recurrent miscarriages (RMs). The use of immunotherapies remains not recommended in the management of couples with RM. This overview of systematic reviews and meta-analysis (SRs-MAs) aims to identify and evaluate the quality of SRs-MAs that studied the effectiveness of immunotherapies in the treatment of RM patients. SRs-MAs were searched in PubMed/Medline, Embase, and Web of Science. SRs-MAs were analyzed using AMSTAR-2, PRISMA 2020, Risk of Bias in Systematic (ROBIS), and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tools to evaluate the methodological quality, reporting quality, risk of bias, and evidence quality of included SRs-MAs, respectively. This review included 20 SRs-MAs that evaluated the following immunotherapies: intravenous immunoglobulin (13 publications), lymphocyte immunotherapy (6 publications), corticosteroids (3 publications), and lipid emulsion (1 publication). SRs-MAs were rated as high methodological, moderate, and critically low quality in 14 (70 %), 1 (5 %), and 5 (25 %) SRs-MAs and high reporting, moderate, and low quality in 13 (65 %), 4 (20 %), and 3 (5 %) SRs-MAs, respectively. The overall risk of bias revealed a low risk of bias for three-quarters of the SRs-MAs. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) analysis resulted in 23 outcomes, of which 4, 3, 5, and 11 results were of high, moderate, low, and very low quality, respectively. An improvement has been observed over the past few years in the quality of systematic reviews (SR)-MAs that have investigated the efficacy of intravenous immunoglobulin, lymphocyte immunotherapy, lipid emulsion therapy, and corticosteroids as a therapy for RM.

Peripheral blood natural killer cell cytotoxicity in recurrent miscarriage: a systematic review and meta-analysis.

Dysregulated natural killer (NK) cells have been associated with recurrent miscarriages (RM). Studies have suggested that high peripheral blood NK cell cytotoxicities (pNKCs) are associated with an increased risk of RM. The aim of this systematic review (SR) and meta-analysis (MAs) is to investigate the difference in pNKC between nonpregnant and pregnant women with RM and controls and determine whether pNKC is reduced by immunotherapy. We searched the PubMed/Medline, Embase, and Web of Science databases. The MAs were conducted to compare pNKCs between women with and without RM before and during pregnancy as well as pre- and post-immunotherapy. Risk of bias in nonrandomized studies was assessed by the Newcastle-Ottawa Scale. Statistical analysis was performed using the Review Manager software. A total of 19 studies were included in the SR and 14 studies in the MAs. The MAs revealed higher pNKCs among nonpregnant women with RM compared to controls (MD, 7.99 95 %CI 6.40-9.58; p < 0.00001). pNKCs were also higher in pregnant women with RM than in pregnant controls (MD, 8.21 95 %CI 6.08-10.34; p < 0.00001). Women with RM showed significantly decreased pNKCs after the immunotherapy compared to before (MD, -8.20 95 %CI -10.20 - -6.19; p < 0, 00001). Additionally, there is an association between high pNKCs and the risk of pregnancy loss in women with RM. However, included studies showed substantial heterogeneities regarding the inclusion criteria of patients, techniques measuring pNKC, and types of immunotherapies. More studies are needed to evaluate the clinical efficiency of pNKCs in managing RM.

Altered profile of plasma phospholipids in woman with recurrent pregnancy loss and recurrent implantation failure treated with lipid emulsion therapy.

BACKGROUND: Recurrent Pregnancy Loss (RPL) and Recurrent Implantation Failure (RIF) are highly heterogeneous condition and many of the mechanisms involved still require elucidation. The aim was to analyze the lipidomic profile in plasma of women with RPL and RIF before and after receiving the Lipid Emulsion Therapy (LET) containing 10% fish oil (SMOFlipid® 20%). METHODS: This study included twenty-six women with RPL or RIF from immunological or inflammatory causes, with elevated natural killer cell levels and divided into a Pregnancy Loss or a Live Birth group according to the outcome. The women received intravenous LET and sample collecting was done before the first, third and fifth dose of LET in the pregnant women. Ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-QTOF MS) and multivariate statistical methods were performed to evaluate the profile of phospholipids present in the women's plasma. RESULTS: An increase of phosphatidylcholines (PC) 40:8 and 36:5 levels with predominance of n6 polyunsaturated fatty acids (PUFA) was observed in plasma lipids of the Pregnancy Loss Group compared to Live Birth Group. We also observed an increase in the relative abundance of n3 PUFA-PC species (42:10 and 36:6) and LysoPC 15:0 with the long term use of LET. CONCLUSION: The greater availability of n3 PUFA in plasma of the pregnant women stemming from LET use can be considered advantageous regarding the alteration of the phospholipid profile and its postulated anti-inflammatory and immunomodulatory role.

COVID-19 and miscarriage: From immunopathological mechanisms to actual clinical evidence.

The association between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the first half of pregnancy and pregnancy loss is still unknown. Infections by other coronaviruses, such as severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), appear to increase the risk of miscarriage. The purpose of this study is to assess whether SARS-CoV-2 infection increases the risk of miscarriage. Firstly, a narrative review of the literature on animal and human studies was performed to analyze the immunopathological mechanisms of SARS-CoV-2 infection during preconception and early pregnancy, by which it may increase the risk of miscarriage. Secondly, a systematic review/meta-analysis of studies was conducted to assess the prevalence of miscarriage in COVID-19 patients diagnosed during pregnancy. Meta-analysis of proportions was used to combine data, and pooled proportions were reported. Seventeen case series and observational studies and 10 prevalence meta-analyses were selected for the review. The estimate of the overall miscarriage rate in pregnant women with COVID-19 was 15.3 % (95 % CI 10.94-20.59) and 23.1 (95 % CI 13.17-34.95) using fixed and random effect models, respectively. Based on the data in the current literature, the miscarriage rate (<22 weeks gestation) in women with SARS-CoV-2 infection is in the range of normal population. Well-designed studies are urgently needed to determine whether SARS-CoV-2 infection increases the risk of miscarriage during periconception and early pregnancy.

Lymphocyte immunotherapy in recurrent miscarriage and recurrent implantation failure.

PROBLEM: Lymphocyte immunotherapy (LIT) emerged in the early 1980s as a new therapeutic proposal for couples with a history of recurrent miscarriages (RM). However, in the early 2000s, the effectiveness of LIT was questioned. Recently, meta-analyses have observed the effectiveness and safety of LIT in treating couples with RM. Some studies evaluated the use of LIT in recurrent implantation failure (RIF) in in vitro fertilization cycles. METHODS: This systematic and narrative review evaluated the data available in the literature regarding the efficacy and safety of the use of LIT. Searches in PubMed/Medline, Embase, and Cochrane Library databases were conducted, using the following keywords: "recurrent miscarriage," "lymphocyte immunotherapy," and "recurrent implantation failure". RESULTS: This review describes the historical aspects of LIT and discusses its protocols, mechanisms of action, side effects, complications, and current evidence of the effectiveness in cases of reproductive failure. It also discusses the use of LIT during the COVID-19 pandemic and new immunological therapies. CONCLUSION: In the vast majority of studies, the use of LIT for RM couples has shown an improvement in pregnancy outcomes. The most of the current studies that support the evidence are quasi-experimental, with few randomized, double-blind studies (Level of evidence III). However, the current evidence are not convincing for the use of LIT in RIF patients.

Lipid emulsion therapy in women with recurrent pregnancy loss and repeated implantation failure: The role of abnormal natural killer cell activity.

Altered immune and/or inflammatory response plays an important role in cases of recurrent pregnancy loss (RPL) and repeated implantation failure (RIF). Exacerbation of the maternal immune response through increased NK cell activity and inflammatory cytokines can cause embryo rejection leading to abortion or embryo implantation failure. Immunosuppressors or immunomodulators can help or prevent this condition. Currently, lipid emulsion therapy (LET) has emerged as a treatment for RPL and RIF in women with abnormal NK cell activity, by decreasing the exacerbated immune response of the maternal uterus and providing a more receptive environment for the embryo. However, the mechanisms by which the intralipid acts to reduce NK cell activity are still unclear. In this review, we focus on the studies that conducted LET to treat patients with RPL and RIF with abnormal NK cell activity. We find that although some authors recommend LET as an effective intervention, more studies are necessary to confirm its effectiveness in restoring NK cell activity to normal levels and to comprehend the underlying mechanisms of the lipids action in ameliorating the maternal environment and improving the pregnancy rate.

Maternal immune responses and obstetrical outcomes of pregnant women with COVID-19 and possible health risks of offspring.

Coronavirus disease 2019 (COVID-19) pandemic has spread rapidly across the world. The vast majority of patients with COVID-19 manifest mild to moderate symptoms but may progress to severe cases or even mortalities. Young adults of reproductive age are the most affected population by SARS-CoV-2 infection. However, there is no consensus yet if pregnancy contributes to the severity of COVID-19. Initial studies of pregnant women have found that COVID-19 significantly increases the risk of preterm birth, intrauterine growth restriction, and low birth weight, which have been associated with non-communicable diseases in offspring. Besides, maternal viral infections with or without vertical transmission have been allied with neurological and behavioral disorders of the offspring. In this review, obstetrical outcomes of women with COVID-19 and possible risks for their offspring are discussed by reviewing maternal immune responses to COVID-19 based on the current evidence. Structural and systemic follow-up of offspring who are exposed to SARS-CoV-2 in-utero is suggested.

COVID-19 and immunomodulation treatment for women with reproductive failures.

COVID-19 pandemic is affecting various areas of health care, including human reproduction. Many women with reproductive failures, during the peri-implantation period and pregnancy, are on the immunotherapy using immune modulators and immunosuppressant due to underlying autoimmune diseases, cellular immune dysfunction, and rheumatic conditions. Many questions have been raised for women with immunotherapy during the COVID-19 pandemic, including infection susceptibility, how to manage women with an increased risk of and active COVID-19 infection. SARS-CoV-2 is a novel virus, and not enough information exists. Yet, we aim to review the data from previous coronavirus outbreaks and current COVID-19 and provide interim guidelines for immunotherapy in women with reproductive failures.

Intrauterine perfusion immunotherapies in recurrent implantation failures: Systematic review.

Studies have investigated the gestational outcomes of new immunological therapies in the treatment of patients with recurrent implantation failure (RIF) in assisted reproductive technology (ART). The objective of this article is to assess the current state of evidence available in the literature on intrauterine perfusion immunotherapies in women undergoing ART treatments. By considering the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA), the authors performed systematic review by searching the databases of PubMed/MEDLINE and Scopus using the following key words: "recurrent implantation failure," "intrauterine infusion," "Platelet-Rich Plasma (PRP)," "Peripheral Blood Mononuclear Cells (PBMC)," "Granulocyte Colony-Stimulating Factor (G-CSF)," and "Human Chorionic Gonadotropin (hCG)." The authors analyzed the indications and the impact of new immunological therapies with intrauterine infusions on the pregnancy outcomes of patients undergoing ART. PRP, PBMC, G-CSF, and hCG were the four most used immunological therapies with intrauterine infusion. These new therapies appear to improve the results of ART treatments in cases of RIF. However, the small number of studies does not allow definitive conclusions about the effectiveness of these therapies.