Intravenous immunoglobulin treatment for secondary recurrent miscarriage: a randomised, double-blind, placebo-controlled trial

Angiogenic factors and the lectin pathway of complement in women with secondary recurrent pregnancy loss

The poor remodeling of placental spiral arteries seen in preeclampsia is also discussed to contribute to recurrent pregnancy loss (RPL) preceded by abnormal angiogenesis and excessive complement activation. Low levels of Mannose-binding-lectin (MBL), a pattern recognition molecule (PRM) of the lectin pathway, have been found in women with RPL. We propose that pregnancy loss is connected to defective angiogenesis with reperfusion damage in the placenta and decreased levels of PRM in the lectin pathway in women with RPL. In this cohort study, we investigate the angiogenic factors and the lectin complement pathway in early pregnancy and their time-dependent relationship with pregnancy outcomes in 76 women with secondary RPL (sRPL) who have at least four prior pregnancy losses and a live birth. We evaluated levels of Angiopoietin-1 (Ang-1), Angiopoietin-2 (Ang-2), Vascular Endothelial Growth Factor (VEGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and the PRMs, MBL, ficolin-1, -2, -3 and an additional soluble PRM, Pentraxin-3, during the 5th, 6th, and 7th gestational weeks. Our results showed that, compared to live births, pregnancies that ended in loss were associated with elevated VEGF levels and decreased levels of the Ang-2/Ang-1 ratio. Also, increasing levels of ficolin-2 were significantly associated with pregnancy loss, with MBL showing no association. Our research suggests that women with sRPL may have inadequate placentation with impaired angiogenesis in pregnancies ending in a loss.

Intravenous immunoglobulin treatment for obstetric antiphospholipid syndrome refractory to conventional therapy: A single-arm, open-labelled multicentre clinical trial

OBJECTIVES

The objective of the study was to compare the efficacy of intravenous immunoglobulin (IVIG) therapy for obstetric antiphospholipid syndrome (APS) refractory to conventional treatment.

METHODS

We conducted a single-arm, open-label multicentre clinical intervention trial. The enrolled criteria were patients with refractory APS who had a history of still or premature birth before 30 weeks of gestational age, even though they had been treated with conventional treatment, i.e. heparin and low-dose aspirin. After confirming the foetal heartbeats, a single course of IVIG (0.4 g/kg body weight daily for 5 days) was added to conventional treatment. The primary outcome was a live birth ratio of >30 weeks of gestational period, and the secondary outcome included improving pregnancy outcomes compared to previous pregnancy.

RESULTS

Twenty-five per cent of patients (2 of 8 cases) achieved a live birth after the 30th week of pregnancy by IVIG-only add-on treatment, which is the same prevalence as the historical control. However, by adding other second-line therapy to IVIG and conventional treatment, further three patients (37.5%) achieved improvements in pregnancy outcome compared to previous treatments. In total, five patients (62.5%) were able to achieve preferable pregnancy outcomes through combination treatment including IVIG.

CONCLUSIONS

This clinical trial could not demonstrate the efficacy of IVIG-only add-on therapy at improving the pregnancy outcomes of patients with obstetric APS refractory to conventional treatment. However, the combination of IVIG with rituximab or statins adding to conventional treatment improved pregnancy outcomes and resulted in more live births. Further studies are needed to investigate the efficacy of multi-targeted therapy to treat obstetric refractory APS.

Reproductive factors and subsequent pregnancy outcomes in patients with prior pregnancy loss

BACKGROUND

At present, individualized interventions can be given to patients with a clear etiology of pregnancy loss to improve the subsequent pregnancy outcomes, but the current reproductive status of the patient cannot be changed. The aim of this study was to investigate the association between female reproductive status and subsequence pregnancy outcome in patients with prior pregnancy loss (PL).

METHODS

A prospective, dynamic population cohort study was carried out at the Second Hospital of Lanzhou University. From September 2019 to February 2022, a total of 1955 women with at least one previous PL were enrolled. Maternal reproductive status and subsequent reproductive outcomes were recorded through an electronic medical record system and follow-up. Logistic regression was used to evaluate the association between reproductive status and the risk of subsequent reproductive outcomes.

RESULTS

Among all patients, the rates of subsequent infertility, early PL, late PL, and live birth were 20.82%, 24.33%, 1.69% and 50.77% respectively. In logistic regression, we found that age (OR 1.08, 95% CI 1.04-1.13) and previous cesarean delivery history (OR 2.46, 95% CI 1.27-4.76) were risk factors for subsequent infertility in patients with PL. Age (OR 1.06, 95% CI 1.03-1.10), age at first pregnancy (OR 1.06, 95% CI 1.03-1.10), BMI (OR 1.06, 95% CI 1.02-1.11), previous PL numbers (OR 1.18, 95% CI 1.04-1.57) and without pre-pregnancy intervention (OR 1.77, 95% CI 1.35-2.24) were risk factors for non-live birth. Age (OR 1.06, 95% CI 1.03-1.09), age at first pregnancy (OR 1.06, 95% CI 1.02-1.09), BMI (OR 1.07, 95% CI 1.02-1.11), previous PL numbers (OR 1.15, 95% CI 1.02-1.31) and without pre-pregnancy intervention (OR 2.16, 95% CI 1.65-2.84) were risk factors for PL.

CONCLUSIONS

The reproductive status of people with PL is strongly correlated with the outcome of subsequent pregnancies. Active pre-pregnancy intervention can improve the subsequent pregnancy outcome.

TRIAL REGISTRATION

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

High doses of intravenous immunoglobulin stimulate regulatory T cell and suppress natural killer cell in women with recurrent pregnancy loss

The aim was to evaluate whether natural killer (NK) cells and regulatory T (Treg) cells were involved in mechanisms underlying beneficial effects of a high dose of intravenous immunoglobulin (IVIG) on recurrent pregnancy losses (RPL) of unexplained etiology. In a double-blind, randomized, placebo-controlled trial of IVIG (400 mg/kg, for 5 days in 4-6 weeks of gestation) in women with RPL, blood samples were collected pre-infusion, one week after infusion (1 w), and eight weeks of gestation/when miscarried (8 w). Levels of NK and Treg cells in peripheral blood were compared between women with IVIG (n = 50) and placebo (n = 49), and between women with IVIG who gave live birth (n = 29) and those who had miscarriage with normal chromosome (n = 12). Effector Treg cell percentages in IVIG group at 1 w (mean 1.43 % vs. 1.03 %) and at 8 w (1.91 % vs. 1.18 %) were higher than those in placebo group (p < 0.01). Total Treg cell percentages in IVIG group at 1 w (4.75 % vs. 4.08 %) and at 8 w (5.55 % vs. 4.47 %) were higher than those in placebo group (p < 0.05). In women with live birth, total Treg cell percentages increased at 8 w (5.52 %, p < 0.001) compared with pre-infusion (4.54 %) and 1 w (4.47 %), while NK cell activity decreased at 1 w (20.18 %, p < 0.001) compared with pre-infusion (26.59 %). IVIG increased Treg cell percentages and suppressed NK cell activity very early in pregnancy, and these were associated with subsequent live birth. Stimulation of Treg cells and suppression of NK cell activity very early in pregnancy may be a mechanism of pharmacological effects of high dose IVIG.

Intravenous immunoglobulin use in patients with unexplained recurrent pregnancy loss

PROBLEM

Recurrent pregnancy loss (RPL) affects up to 4% of couples attempting to conceive. RPL is unexplained in over 50% of cases and no effective treatments exist. Due to the immune system's pivotal role during implantation and pregnancy, immune-mediated RPL may be suspected and immunomodulatory treatments like intravenous immunoglobulin (IVIg) have been administered but remain controversial. The goal of our study was to evaluate our center's 6 year-outcomes and to develop a framework for IVIg use in RPL.

METHOD OF THE STUDY

Retrospective, single-center cohort study. All patients having received IVIg for unexplained RPL at the McGill Reproductive Immunology Clinic (MRIC) from January 2014 to December 2020 were included if maternal age was <42 years, body mass index (BMI) < 35 kg/m² , non-smoker and having had ≥3 consecutive RPL despite previous treatment with aspirin and progesterone. IVIg 0.6-0.8 g/kg was given prior to conception and monthly during pregnancy until 16-20 weeks' gestation. We compared IVIg treated patient's outcomes to a separate "natural history cohort". This cohort was composed of patients consulting at the McGill recurrent pregnancy loss clinic and the MRIC over a 2-year period (January 2020 to December 2021) with similar inclusion criteria as the treatment cohort but did not receive IVIg or other immunomodulatory treatments. The association of IVIg with outcomes (compared to no IVIg) was evaluated among the groups of patients with primary RPL and secondary RPL. The primary outcome was live birth rate (LBR), secondary outcomes included IVIg safety, obstetrical, and neonatal complications.

RESULTS

Among 169 patients with unexplained RPL that were included in the study, 111 had primary RPL (38 exposed to IVIg and 83 controls) and 58 had secondary RPL (nine exposed to IVIG and 49 controls). Among patients with primary RPL (n = 111), the LBR was 64.3% (18/28) among patient exposed to IVIg compared to 43.4% (36/83) in controls (p = 0.079); regression analysis adjusting for BMI and number of previous miscarriages showed benefit favoring the use of IVIg (OR = 3.27, CI 95% (1.15-10.2), p = 0.03) when evaluating for live birth. In the subgroup of patients with ≥5 previous RPL and primary RPL (n = 31), IVIg was associated with higher LBR compared to control (10/15 (66.7%) vs. 3/16 (18.8%); p = 0.0113) but not the in the sub-group of patients with <5 miscarriages and primary RPL (8/13 (61.5%) vs. 33/67 (49.3%); p = 0.548). IVIG treatment did not improve LBR in patients with secondary RPL in our study (3/9 (33.3%) vs. 23/49 (47%); p = 0.495). There were no serious adverse events in the IVIg treatment group, obstetrical/neonatal complications were similar between groups.

CONCLUSION

IVIg may be an effective treatment for patients with RPL if appropriately used in specific groups of patients. IVIg is a blood product and subject to shortages especially with unrestricted off-label use. We propose considering IVIg in well-selected patients with high order RPL who have failed standard medical therapy. Further mechanistic studies are needed to understand immune-mediated RPL and IVIg's mode of action. This will enable further refinement of treatment criteria and the development of standardized protocol for its use in RPL.

Successful Pregnancy and Delivery at Term Following Intravenous Immunoglobulin Therapy with Heparin for Unexplained Recurrent Pregnancy Loss Suspected of Immunological Abnormalities: A Case Report and Brief Literature Review

About 60% of cases of recurrent pregnancy loss have unexplained etiology. Immunotherapy for unexplained recurrent pregnancy loss is still unestablished. A 36-year-old woman, not obese, had a stillbirth at 22 gestational weeks and a spontaneous abortion at 8 weeks. She had been examined for recurrent pregnancy loss at previous clinics with no significant findings. When she visited our clinic, a hematologic test showed a Th1/Th2 ratio imbalance. Ultrasonography, hysteroscopy, and semen analysis showed no abnormalities. She successfully conceived by embryo transfer in hormone replacement therapy cycle. However, she had a miscarriage at 19 weeks. The baby had no deformities, but a chromosomal test was not performed, according to the parents' will. The placenta pathologically suggested hemoperfusion problems. Her and her husband's chromosomal tests showed normal karyotypes. Other examinations revealed a repeated Th1/Th2 ratio imbalance and a high resistance index of uterine radial artery blood flow. She was administered low-dose aspirin, intravenous immunoglobulin, and unfractionated heparin after the second embryo was transferred. Her baby was healthily born by cesarean section at 40 weeks. Intravenous immunoglobulin therapy can be a choice for recurrent miscarriage without risk factors because it has clinically beneficial influences on the patient's immunological aberration.

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

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

Intravenous immunoglobulin treatment in women with four or more recurrent pregnancy losses: A double-blind, randomised, placebo-controlled trial

BACKGROUND

There is no effective treatment for women with unexplained recurrent pregnancy loss (RPL). We aimed to investigate whether treatment with a high dose of intravenous immunoglobulin (IVIG) in early pregnancy can improve pregnancy outcomes in women with unexplained RPL.

METHODS

In a double-blind, randomised, placebo-controlled trial, women with primary RPL of unexplained aetiology received 400 mg/kg of IVIG daily or placebo for five consecutive days starting at 4-6 weeks of gestation. They had experienced four or more miscarriages except biochemical pregnancy loss and at least one miscarriage of normal chromosome karyotype. The primary outcome was ongoing pregnancy rate at 22 weeks of gestation, and the live birth rate was the secondary outcome. We analysed all women receiving the study drug (intention-to-treat, ITT) and women except those who miscarried due to fetal chromosome abnormality (modified-ITT). This study is registered with ClinicalTrials.gov number, NCT02184741.

FINDINGS

From June 3, 2014 to Jan 29, 2020, 102 women were randomly assigned to receive IVIG (n = 53) or placebo (n = 49). Three women were excluded; therefore 50 women received IVIG and 49 women received placebo in the ITT population. The ongoing pregnancy rate at 22 weeks of gestation (31/50 [62·0%] vs. 17/49 [34·7%]; odds ratio [OR] 3·07, 95% CI 1·35-6·97; p = 0·009) and the live birth rate (29/50 [58·0%] vs. 17/49 [34·7%]; OR 2·60, 95% CI 1·15-5·86; p = 0·03) in the IVIG group were higher than those in the placebo group in the ITT population. The ongoing pregnancy rate at 22 weeks of gestation (OR 6·27, 95% CI 2·21-17·78; p < 0·001) and the live birth rate (OR 4·85, 95% CI 1·74-13·49; p = 0·003) significantly increased in women who received IVIG at 4-5 weeks of gestation as compared with placebo, but these increases were not evident in women who received IVIG at 6 weeks of gestation. Four newborns in the IVIG group and none in the placebo group had congenital anomalies (p = 0·28).

INTERPRETATION

A high dose of IVIG in very early pregnancy improved pregnancy outcome in women with four or more RPLs of unexplained aetiology.

FUNDING

The Japan Blood Products Organization.

Outcomes of Empirical Treatment With Intravenous Immunoglobulin G Combined With Low-Dose Aspirin in Women With Unexplained Recurrent Pregnancy Loss

BACKGROUND

To assess the clinical efficacy of intravenous immunoglobulin G (IVIG) administration combined with low-dose aspirin in women with unexplained recurrent pregnancy loss (RPL).

METHODS

We retrospectively analyzed the medical records of patients who had been diagnosed with unexplained RPL and treated with IVIG and low-dose aspirin between January 2000 and March 2020 at Asan Medical Center. We analyzed pregnancy outcomes and their association with the percentage of natural killer (NK) cells.

RESULTS

The study analyzed a total of 93 patients and 113 natural and assisted reproductive technology pregnancy cycles. The live birth rate per cycle was 73.5% (83/113), and the term delivery rate was 86.7% (72/83). The live birth rate was high regardless of the type of RPL, method of pregnancy, timing of IVIG treatment, and presence or absence of autoantibodies. In addition, the live birth rate was significantly higher in patients who received IVIG more than once, compared with patients who received IVIG only once (77.8% vs. 42.9%, P = 0.006). There was no significant association between the NK cell counts and live birth rate (65.5% in the group with NK cell < 12%, and 69.7% in that with NK cell ≥ 12%, P = 0.725). Among all patients, 87.6% had no complications, and there were no congenital malformation among newborn babies.

CONCLUSION

IVIG combined with low-dose aspirin treatment showed favorable pregnancy outcomes regardless of the patient's NK cell counts (%).

Pathogenesis, Diagnosis and Management of Obstetric Antiphospholipid Syndrome: A Comprehensive Review

Antiphospholipid syndrome is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity associated with persistent antiphospholipid antibody positivity. Cases fulfilling the Sydney criteria for obstetric morbidity with no previous thrombosis are known as obstetric antiphospholipid syndrome (OAPS). OAPS is the most identified cause of recurrent pregnancy loss and late-pregnancy morbidity related to placental injury. Cases with incomplete clinical or laboratory data are classified as obstetric morbidity APS (OMAPS) and non-criteria OAPS (NC-OAPS), respectively. Inflammatory and thrombotic mechanisms are involved in the pathophysiology of OAPS. Trophoblasts, endothelium, platelets and innate immune cells are key cellular players. Complement activation plays a crucial pathogenic role. Secondary placental thrombosis appears by clot formation in response to tissue factor activation. New risk assessment tools could improve the prediction of obstetric complication recurrences or thromboses. The standard-of-care treatment consists of low-dose aspirin and prophylactic low molecular weight heparin. In refractory cases, the addition of hydroxychloroquine, low-dose prednisone or IVIG improve pregnancy outcomes. Statins and eculizumab are currently being tested for treating selected OAPS women. Finally, we revisited recent insights and concerns about the pathophysiology, diagnosis and management of OAPS.

In vitro fertilization-embryo transfer in patients with unexplained recurrent pregnancy loss

Background:

Empiric therapy for patients with unexplained recurrent pregnancy loss (URPL) is not precise. Some patients will ask for assisted reproductive technology due to secondary infertility or advanced maternal age. The clinical outcomes of URPL patients who have undergone in vitro fertilization-embryo transfer (IVF-ET) require elucidation. The IVF outcome and influencing factors of URPL patients need further study.

Methods:

A retrospective cohort study was designed, and 312 infertile patients with URPL who had been treated during January 2012 to December 2015 in the Reproduction Center of Peking University Third Hospital were included. By comparing clinical outcomes between these patients and those with tubal factor infertility (TFI), the factors affecting the clinical outcomes of URPL patients were analyzed.

Results:

The clinical pregnancy rate (35.18% vs. 34.52% in fresh ET cycles, P = 0.877; 34.48% vs. 40.27% in frozen-thawed ET cycles, P = 0.283) and live birth rate (LBR) in fresh ET cycles (27.67% vs. 26.59%, P = 0.785) were not significantly different between URPL group and TFI group. URPL group had lower LBR in frozen-thawed ET cycles than that of TFI group (23.56% vs. 33.56%, P = 0.047), but the cumulative LBRs (34.69% vs. 38.26%, P = 0.368) were not significantly different between the two groups. The increased endometrial thickness (EMT) on the human chorionic gonadotropin day (odds ratio [OR]: 0.848, 95% confidence interval [CI]: 0.748–0.962, P = 0.010) and the increased number of eggs retrieved (OR: 0.928, 95% CI: 0.887–0.970, P = 0.001) were protective factors for clinical pregnancy in stimulated cycles. The increased number of eggs retrieved (OR: 0.875, 95% CI: 0.846–0.906, P < 0.001), the increased two-pronucleus rate (OR: 0.151, 95% CI: 0.052–0.437, P < 0.001), and increased EMT (OR: 0.876, 95% CI: 0.770–0.997, P = 0.045) in ET day were protective factors for the cumulative live birth outcome.

Conclusion:

After matching ages, no significant differences in clinical outcomes were found between the patients with URPL and the patients with TFI. A thicker endometrium and more retrieved oocytes increase the probability of pregnancy in fresh transfer cycles, but a better normal fertilization potential will increase the possibility of a live birth.

Alteration of vaginal microbiota in patients with recurrent miscarriage

The aim of this study was to characterise the structure of vaginal microbiota in unexplained recurrent miscarriage (RM). The vaginal bacterial communities of 16 patients with RM and 20 healthy volunteers were sampled. Then, the microbiomes of bacterial profiles of RM patients and healthy volunteers were compared by sequencing the V3-V4 regions of the bacterial 16S ribosomal RNA gene using the Illumina MiSeq platform (Illumina, San Diego, CA). Taxonomic analysis demonstrated that abundance of Lactobacillus and Gardnerella were significantly different between the RM and control groups. Furthermore, at the genus level, Lactobacillus was the most dominant genus in the two groups. Statistically significant differences were observed in three genera between RM and control groups. In the control group, two bacterial taxa were significantly more abundant (Lactobacillus and Gardnerella), while only one taxon was overrepresented in the RM group (Atopobium). These present findings provide experimental evidence supporting vaginal microbiota dysbiosis in women with RM.Impact statementWhat is already known on this subject? Currently, bacterial vaginosis is thought to be mainly due to the vaginal dysbacteriosis, which can induce unexplained recurrent miscarriage, premature rupture of membranes, low birth weight premature birth, premature birth, chorioamnionitis and series of diseases.What do the results of this study add? The current study demonstrated that Lactobacillus and Gardnerella were significantly decreased in RM patients compared to healthy control, while Atopobium was overrepresented in the RM group.What are the implications of these findings for clinical practice and/or further research? Clinically, women with RM might benefit from vaginal microbiota treatment, adjuvant therapy with Lactobacillus-based live biotherapeutics.

Crosstalk Between Trophoblasts and Decidual Immune Cells: The Cornerstone of Maternal-Fetal Immunotolerance

The success of pregnancy relies on the fine adjustment of the maternal immune system to tolerate the allogeneic fetus. Trophoblasts carrying paternal antigens are the only fetal-derived cells that come into direct contact with the maternal immune cells at the maternal–fetal interface. The crosstalk between trophoblasts and decidual immune cells (DICs) via cell–cell direct interaction and soluble factors such as chemokines and cytokines is a core event contributing to the unique immunotolerant microenvironment. Abnormal trophoblasts–DICs crosstalk can lead to dysregulated immune situations, which is well known to be a potential cause of a series of pregnancy complications including recurrent spontaneous abortion (RSA), which is the most common one. Immunotherapy has been applied to RSA. However, its development has been far less rapid or mature than that of cancer immunotherapy. Elucidating the mechanism of maternal–fetal immune tolerance, the theoretical basis for RSA immunotherapy, not only helps to understand the establishment and maintenance of normal pregnancy but also provides new therapeutic strategies and promotes the progress of immunotherapy against pregnancy-related diseases caused by disrupted immunotolerance. In this review, we focus on recent progress in the maternal–fetal immune tolerance mediated by trophoblasts–DICs crosstalk and clinical application of immunotherapy in RSA. Advancement in this area will further accelerate the basic research and clinical transformation of reproductive immunity and tumor immunity.

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

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

A systemic review of intravenous immunoglobulin G treatment in women with recurrent implantation failures and recurrent pregnancy losses

Over the last few decades, the advancement in reproductive technologies and protocols to improve embryo quality through culture techniques and genetic testing to eliminate chromosomally abnormal embryos resulted in better pregnancy rates and outcomes after fertility treatments. Unfortunately, some patients still struggle with recurrent implantation failures (RIFs) and recurrent pregnancy losses (RPLs). Immune etiologies have been attributed to play an important role in some of those patients. Maintaining a pre-conceptional anti-inflammatory environment for implantation and pregnancy continuation yields superior results. Intravenous immunoglobulin G (IVIG) treatment has been reported to enhance reproductive outcome in patients with RIF and RPL with immune dysregulations. In this systemic review, we analyzed outcomes of IVIG trials for RIF and RPL, its mechanism of action, dosing, administration, side-effects, and evidence for its use in women with RIF and RPL.

Update on the Use of Intravenous Immunoglobulin in Pregnancy

Intravenous immunoglobulin (IVIG) was first administered to humans in the 1980s. The mechanism of action of IVIG is still a subject of debate but the pharmacokinetics have been well characterized, albeit outside of pregnancy. IVIG has been used in pregnancy to treat several nonobstetrical and obstetrical-related conditions. However, current evidence suggests that IVIG use during pregnancy can be recommended for 1) in utero diagnosis of neonatal alloimmune thrombocytopenia; 2) gestational alloimmune liver disease; 3) hemolytic disease of the fetus and newborn for early-onset severe intrauterine disease; 4) antiphospholipid syndrome (APS) when refractory to or contraindicated to standard treatment, or in catastrophic antiphospholipid syndrome; and 5) immune thrombocytopenia when standard treatment is ineffective or rapid increase of platelet counts is needed. All recommendations are based on case series and cohort studies without randomized trials usually because of the rare prevalence of the conditions, the high incidence of adverse outcomes if left untreated, and ethical concerns. In contrast, IVIG therapy cannot be recommended for recurrent pregnancy loss, and the use of IVIG in subgroups of those with recurrent pregnancy loss requires further investigations. For non-obstetrical-related conditions, we recommend using IVIG as indicated for nonpregnant patients. In conclusion, the use of IVIG during pregnancy is an effective treatment in some obstetrical-related conditions with rare serious maternal side effects. However, the precise mechanisms of action and the long-term immunologic effects on the fetus and neonate are poorly understood and merit further investigations.

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

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

Recurrent pregnancy loss

Recurrent pregnancy loss is a distressing pregnancy disorder experienced by ~2.5% of women trying to conceive. Recurrent pregnancy loss is defined as the failure of two or more clinically recognized pregnancies before 20-24 weeks of gestation and includes embryonic and fetal losses. The diagnosis of an early pregnancy loss is relatively straightforward, although progress in predicting and preventing recurrent pregnancy loss has been hampered by a lack of standardized definitions, the uncertainties surrounding the pathogenesis and the highly variable clinical presentation. The prognosis for couples with recurrent pregnancy loss is generally good, although the likelihood of a successful pregnancy depends on maternal age and the number of previous losses. Recurrent pregnancy loss can be caused by chromosomal errors, anatomical uterine defects, autoimmune disorders and endometrial dysfunction. Available treatments target the putative risk factors of pregnancy loss, although the effectiveness of many medical interventions is controversial. Regardless of the underlying aetiology, couples require accurate information on their chances of having a baby and appropriate support should be offered to reduce the psychological burden associated with multiple miscarriages. Future research must investigate the pathogenesis of recurrent pregnancy loss and evaluate novel diagnostic tests and treatments in adequately powered clinical trials.

NLRP3 inflammasome: a new therapeutic target for high-risk reproductive disorders?

ABSTRACT

The NOD-like receptor protein 3 (NLRP3) inflammasome is a key regulator of the host's immune response, and many immune and metabolic disorders are linked to its activation. This review aimed to investigate and clarify the relationship between this inflammasome and high-risk reproductive disorders. Papers cited here were retrieved from PubMed up to August 2020 using the keywords "NLRP3" or "NALP3", "caspase-1", "endometriosis", "gestational diabetes", "interleukin (IL)-18", "IL-1β", "pre-eclampsia (PE)", "preterm birth", "polycystic ovarian syndrome (PCOS)", "recurrent spontaneous abortion (RSA)", and combinations of these terms. The results show that NLRP3 inflammasome is associated with various high-risk reproductive disorders and many inflammatory factors are secreted during its activation, such as IL-1β induced during the development of endometriosis. PCOS is also associated with activation of the NLRP3 inflammasome, especially in overweight patients. It also participates in the pathogenesis of RSA and is activated in fetal membranes before preterm birth. The placentas of pregnant women with PE show higher expression of the NLRP3 inflammasome, and gestational diabetes mellitus occurs simultaneously with its activation. Current evidence suggest that the NLRP3 inflammasome plays an important role in female reproductive disorders. New treatment and management methods targeting it might help reduce the incidence of such disorders and improve neonatal outcomes.

Immunotherapy to improve pregnancy outcome in women with abnormal natural killer cell levels/activity and recurrent miscarriage or implantation failure: A systematic review and meta-analysis

There is a trend towards offering immunotherapy to women with unexplained reproductive failure based on abnormal Natural Killer (NK) cell levels. Previous systematic reviews evaluating immunotherapy usage have not focused on women with abnormal level of NK cells. To address the gap in literature, this systematic review aims to evaluate the efficacy of immunotherapy to improve pregnancy outcome in women with recurrent miscarriage (RM) or implantation failure (RIF) specifically selected based on abnormal levels and/or activity of NK cells. Six databases were searched for peer-reviewed studies following PRISMA guidelines. Risk of bias assessment was conducted using RoB2 for randomized controlled trials (RCT) and ROBINS-I for non-RCT. Of 1025 studies identified, seven studies on intravenous immunoglobulin (IVIG) (four), prednisolone (one), etanercept (one) and intralipid (one) were included. Meta-analysis of the non-RCT IVIG studies (557 participants; 312 intervention, 245 controls) showed livebirth in favour of intervention (RR 2.57; 95 % CI = 1.79-3.69; p < 0.05), however there were significant heterogeneity (I² = 62 %) and moderate to severe risk of bias in these studies. Individual RCTs reported improved livebirth outcome in etanercept, intralipid and prednisolone and this was significant in the former two (p < 0.05). In conclusion, there may be some benefit of immunotherapy, but paucity of high quality evidence means that it is not possible to support the use of immunotherapy even when selected based on abnormal NK cell level/activity. Further research with application of scientifically validated immunological biomarkers in well-planned large scale RCTs will determine whether immunotherapy is beneficial in this subpopulation of women.

Tregitopes regulate the tolerogenic immune response and decrease the foetal death rate in abortion-prone mouse matings

The imbalance in immune tolerance may cause the variety of reproductive failures. An intravenous immunoglobulin infusion (IVIg) therapy is used to improve the live birth rate in women suffering from recurrent pregnancy loss, recurrent spontaneous abortions and recurrent implantation failures. However, the results of IVIg studies are still inconclusive as IVIg infusion in women suffering from pregnancy loss is sometimes ineffective. One of the mechanisms of action of this treatment is inhibition of B cells differentiation and expansion of Tregs and secretion of interleukin 10. It was proposed that immunomodulatory effects of IVIg may be attributed to tregitopes - self-IgG-derived epitopes present in the structure of immunoglobulins. Similarly to IVIg, tregitopes cause the expansion of Tregs and secretion of antigen-specific effector cytokine response. Here, we studied whether the administration of mouse tregitope 167 and/or 289 can prevent abortions in mouse abortion-prone mouse matings. We revealed that tregitopes reduce the foetal death rate. This may be driven by observed higher pool of peripheral Tregs, increased production of IL-10 by Tregs and Bregs and/or maintaining the tolerogenic phenotype of antigen-presenting cells. We believe that our findings may indicate a potential alternative to IVIg for therapeutic intervention in case of pregnancy failures.

Evaluation of T cell cytokines and their role in recurrent miscarriage

Recurrent miscarriage (RM) is defined as two or more consecutive pregnancy losses that affect approximately 5% of conceived women worldwide. RM is a multi-factorial reproductive problem and has been associated with parental chromosomal abnormalities, embryonic chromosomal rearrangements, uterine anomalies, autoimmune disorders, endocrine dysfunction, thrombophilia, life style factors, and maternal infections. However, the exact cause is still undecided in remaining 50% of cases. Immunological rejection of the embryo due to exacerbated maternal immune reaction against paternal embryonic antigens has been set forth as one of the significant reason for RM. The accurate means that shield the embryo during normal pregnancy from the attack of maternal immune network and dismissal are inadequately implicit. However, it is suggested that the genetically irreconcilable embryo escapes maternal immune rejection due to communication among many vital cytokines exuded at maternal-embryonic interface both by maternal and embryonic cells. Previous investigations suggested the Th1/Th2 dominance in altered immunity of RM patients, according to which the allogenic embryo flees maternal T cell reaction by inclining the Th0 differentiation toward Th2 pathway resulting into diminished pro-inflammatory Th1 immunity. However, recently pro-inflammatory Th17 cells and immunoregulatory Treg cells have been discovered as essential immune players in RM besides Th1/Th2 components. Cytokines are believed to develop a complicated regulatory network so as to establish a state of homeostasis between the semi-allogenic embryo and the maternal immune system. However, an adverse imbalance among cytokines at maternal-embryonic interface perhaps due to their gene polymorphisms may render immunoregulatory means not enough to re-establish homeostasis and thus may collapse pregnancy.

The optimal timing of immunotherapy may improve pregnancy outcome in women with unexplained recurrent pregnancy loss: A perspective follow-up study in northeastern China

PROBLEM

To determine whether patients with unexplained recurrent pregnancy loss (URPL) can benefit from pre-conception immunotherapy or on the early phase of the first trimester.

METHOD OF STUDY

The prospective follow-up study which involved pre-conception patients diagnosed with URPL following rigorous etiology screening in the medical center of recurrent pregnancy loss. In this study, pre-conception immunotherapy included lymphocyte immunotherapy (pre-LIT). Post-conception immunotherapy (post-IM) included LIT or intravenous immunoglobulin (IVIG). Patients were recommended to undergo post-IM immediately from human chorionic gonadotrophin (hCG) elevation. Autoimmune antibodies (AIA) and anti-paternal lymphocytotoxic antibodies (APLA) were tested before and after pre-LIT. Favorable outcome was defined as pregnancy over 14 weeks. Unfavorable outcomes included biochemical pregnancy loss (BPL) and pregnancy loss with clear implantation location (PLCIL).

RESULTS

In this study, URPL accounted for 12.9% of recurrent pregnancy loss (217/1682). Frequency of BPL was significantly lower in patients with post-IM than that without post-IM [2.8% vs 28.2%; adjusted relative risk (aRR), 0.06; 95% confidence interval (CI), 0.01-0.24]. There was a significant positive conversion in the AIA induced by pre-LIT (0.0% vs 31.0%). Frequency of PLCIL in patients with positive iatrogenic AIA conversion induced by pre-LIT was higher than that in patients without AIA conversion [30.4% vs 5.8%; aRR, 7.53; 95% CI, 1.31-43.34].

CONCLUSION

Pre-LIT of patients with URPL contributed to a positive iatrogenic AIA conversion, which was associated with an increased risk of PLCIL. Post-IM immediately initiated from the time of hCG elevation can reduce the incidence of BPL.

Treatment with intravenous immunoglobulin in patients with recurrent pregnancy loss: An update

Intravenous immunoglobulin (IVIg) has a documented clinical effect in many autoimmune diseases and has so far been tested in >10 randomised controlled trials (RCTs) in women with recurrent pregnancy loss (RPL). The results of the RCTs have, however, been very divergent. In meta-analyses of all trials, no significant impact on live birth rate has been reported. In contrast, in sensitivity analyses, IVIg significantly increased live birth rates when initiated prior to conception and it had a borderline significant therapeutic effect in women with secondary RPL. Higher dosages of IVIg and serological signs of autoimmunity in the treated patients tended to increase the success rate after treatment. A follow-up study of patients from our recent RCT also supports a significant therapeutic effect in patients who had received IVIg before conception. The lessons learned from the published trials and meta-analyses should be incorporated in the design of future RCTs of IVIg in the treatment of RPL.

The role of immunotherapy in in vitro fertilization and recurrent pregnancy loss: a systematic review and meta-analysis

OBJECTIVE

To study the current evidence on the role of immunotherapy in IVF and in the management of recurrent pregnancy loss (RPL).

DESIGN

Systematic review and meta-analysis.

SETTING

A literature search was performed using MEDLINE, PUBMED, CINAHL, and EMBASE until May 2017. Only randomized controlled trials were included, and a meta-analysis was carried out where appropriate.

PATIENT(S)

Women undergoing IVF treatment with or without a history of recurrent implantation failure and women with idiopathic RPL.

INTERVENTION(S)

Assessment of the efficacy of commonly used immunomodulators such as IV use of [1] immunoglobulin, [2] lymphocyte immunotherapy and [3] intralipid; intrauterine infusion of [4] granulocyte colony-stimulating factor and [5] peripheral blood mononuclear cells; subcutaneous administration of [6] TNF-alpha inhibitors, [7] leukaemia inhibitory factor; and oral administration of [8] glucocorticoids.

MAIN OUTCOME MEASURE(S)

The primary outcomes were live birth rate and miscarriage rate; secondary outcome was clinical pregnancy rate.

RESULT(S)

Of the 7,226 publications identified, 53 were selected during the initial screening; 30 satisfied the selection criteria and were included in this review.

CONCLUSION(S)

The available medical literature shows controversial results about the role of immunotherapy when used for improving reproductive outcomes. This study did not show a role for immunotherapy in improving the live birth rate in women undergoing IVF treatment or in the prevention of idiopathic RPL. Currently, immunotherapy should be used in the context of research and should not be used in routine clinical practice to improve reproductive outcomes.

Outcomes in prevention and management of miscarriage trials: a systematic review

BACKGROUND

There is a substantial body of research evaluating ways to prevent and manage miscarriage, but all studies do not report on the same outcomes.

OBJECTIVE

To review systematically, outcomes reported in existing miscarriage trials.

SEARCH STRATEGY

MEDLINE, Embase, CINAHL, and Cochrane were searched from inception until January 2017.

SELECTION CRITERIA

Randomised controlled trials (RCTs) reporting prevention or management of miscarriage. Miscarriage was defined as a pregnancy loss in the first trimester.

DATA COLLECTION AND ANALYSIS

Data about the study characteristics, primary, and secondary outcomes were extracted.

MAIN RESULTS

We retrieved 1553 titles and abstracts, from which 208 RCTs were included. For prevention of miscarriage, the most commonly reported primary outcome was live birth and the top four reported outcomes were pregnancy loss/stillbirth (n = 112), gestation of birth (n = 68), birth dimensions (n = 65), and live birth (n = 49). For these four outcomes, 58 specific measures were used for evaluation. For management of miscarriage, the most commonly reported primary outcome was efficacy of treatment. The top four reported outcomes were bleeding (n = 186), efficacy of miscarriage treatment (n = 105), infection (n = 97), and quality of life (n = 90). For these outcomes, 130 specific measures were used for evaluation.

CONCLUSIONS

Our review found considerable variation in the reporting of primary and secondary outcomes along with the measures used to assess them. There is a need for standardised patient-centred clinical outcomes through the development of a core outcome set; the work from this systematic review will form the foundation of the core outcome set for miscarriage.

TWEETABLE ABSTRACT

There is disparity in the reporting of outcomes and the measures used to assess them in miscarriage trials.

Alteration of vaginal microbiota in patients with unexplained recurrent miscarriage

The way in which a balanced vaginal microbiome helps prevent gynecological diseases in women and maintain health remains to be fully elucidated. In the present study, the potential effect of aberrations in the vaginal flora on unexplained recurrent miscarriage (RM) was investigated. The vaginal bacterial communities of 10 patients with unexplained RM and 10 healthy volunteers were sampled and subjected to sequencing analysis of the V3-V4 regions of the bacterial 16S ribosomal RNA gene using the Illumina MiSeq platform. Beta diversity analysis/principal component analysis indicated that bacterial community structures were different between the RM and control groups. A lower microbiota diversity in samples from RM patients was revealed by alpha diversity estimation. Taxonomic analysis demonstrated that abundance of three types of phyla (Firmicutes, Actinobacteria and Bacteroidetes) was significantly different between the RM and the normal control group. Furthermore, at the genus level, Lactobacillus was the most dominant genus in the two groups. Statistically significant differences were observed in 5 genera between the two groups. In the RM group, 3 bacterial taxa (Atopobium, Prevotella and Streptococcus) were significantly more abundant, while only 2 taxa were overrepresented in the control group (Lactobacillus and Gardnerella). In conclusion, the present results provide experimental evidence supporting dysbiosis of the vaginal flora in women with RM.

Care prior to and during subsequent pregnancies following stillbirth for improving outcomes

BACKGROUND

Stillbirth affects at least 2.6 million families worldwide every year and has enduring consequences for parents and health services. Parents entering a subsequent pregnancy following stillbirth face a risk of stillbirth recurrence, alongside increased risks of other adverse pregnancy outcomes and psychosocial challenges. These parents may benefit from a range of interventions to optimise their short- and longer-term medical health and psychosocial well-being.

OBJECTIVES

To assess the effects of different interventions or models of care prior to and during subsequent pregnancies following stillbirth on maternal, fetal, neonatal and family health outcomes, and health service utilisation.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (6 June 2018), along with ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) (18 June 2018).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-randomised controlled trials (qRCTs). Trials using a cluster-randomised design were eligible for inclusion, but we found no such reports. We included trials published as abstract only, provided sufficient information was available to allow assessment of trial eligibility and risk of bias. We excluded cross-over trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for eligibility and undertook data extraction and 'Risk of bias' assessments. We extracted data from published reports, or sourced data directly from trialists. We checked the data for accuracy and resolved discrepancies by discussion or correspondence with trialists, or both. We conducted an assessment of the quality of the evidence using the GRADE approach.

MAIN RESULTS

We included nine RCTs and one qRCT, and judged them to be at low to moderate risk of bias. Trials were carried out between the years 1964 and 2015 and took place predominantly in high-income countries in Europe. All trials assessed medical interventions; no trials assessed psychosocial interventions or incorporated psychosocial aspects of care. Trials evaluated the use of antiplatelet agents (low-dose aspirin (LDA) or low-molecular-weight heparin (LMWH), or both), third-party leukocyte immunisation, intravenous immunoglobulin, and progestogen. Trial participants were women who were either pregnant or attempting to conceive following a pregnancy loss, fetal death, or adverse outcome in a previous pregnancy.We extracted data for 222 women who had experienced a previous stillbirth of 20 weeks' gestation or more from the broader trial data sets, and included them in this review. Our GRADE assessments of the quality of evidence ranged from very low to low, due largely to serious imprecision in effect estimates as a result of small sample sizes, low numbers of events, and wide confidence intervals (CIs) crossing the line of no effect. Most of the analyses in this review were not sufficiently powered to detect differences in the outcomes assessed. The results presented are therefore largely uncertain.Main comparisonsLMWH versus no treatment/standard care (three RCTs, 123 women, depending on the outcome)It was uncertain whether LMWH reduced the risk of stillbirth (risk ratio (RR) 2.58, 95% CI 0.40 to 16.62; 3 trials; 122 participants; low-quality evidence), adverse perinatal outcome (RR 0.81, 95% CI 0.20 to 3.32; 2 trials; 77 participants; low-quality evidence), adverse maternal psychological effects (RR 1.00, 95% CI 0.07 to 14.90; 1 trial; 40 participants; very low-quality evidence), perinatal mortality (RR 2.58, 95% CI 0.40 to 16.62; 3 trials; 122 participants; low-quality evidence), or any preterm birth (< 37 weeks) (RR 1.01, 0.58 to 1.74; 3 trials; 114 participants; low-quality evidence). No neonatal deaths were reported in the trials assessed and no data were available for maternal-infant attachment. There was no clear evidence of a difference between the groups among the remaining secondary outcomes.LDA versus placebo (one RCT, 24 women)It was uncertain whether LDA reduced the risk of stillbirth (RR 0.85, 95% CI 0.06 to 12.01), neonatal death (RR 0.29, 95% CI 0.01 to 6.38), adverse perinatal outcome (RR 0.28, 95% CI 0.03 to 2.34), perinatal mortality, or any preterm birth (< 37 weeks) (both of the latter RR 0.42, 95% CI 0.04 to 4.06; all very low-quality evidence). No data were available for adverse maternal psychological effects or maternal-infant attachment. LDA appeared to be associated with an increase in birthweight (mean difference (MD) 790.00 g, 95% CI 295.03 to 1284.97 g) when compared to placebo, but this result was very unstable due to the extremely small sample size. Whether LDA has any effect on the remaining secondary outcomes was also uncertain.Other comparisonsLDA appeared to be associated with an increase in birthweight when compared to LDA + LMWH (MD -650.00 g, 95% CI -1210.33 to -89.67 g; 1 trial; 29 infants), as did third-party leukocyte immunisation when compared to placebo (MD 1195.00 g, 95% CI 273.35 to 2116.65 g; 1 trial, 4 infants), but these results were again very unstable due to extremely small sample sizes. The effects of the interventions on the remaining outcomes were also uncertain.

AUTHORS' CONCLUSIONS

There is insufficient evidence in this review to inform clinical practice about the effectiveness of interventions to improve care prior to and during subsequent pregnancies following a stillbirth. There is a clear and urgent need for well-designed trials addressing this research question. The evaluation of medical interventions such as LDA, in the specific context of stillbirth prevention (and recurrent stillbirth prevention), is warranted. However, appropriate methodologies to evaluate such therapies need to be determined, particularly where clinical equipoise may be lacking. Careful trial design and multicentre collaboration is necessary to carry out trials that would be sufficiently large to detect differences in statistically rare outcomes such as stillbirth and neonatal death. The evaluation of psychosocial interventions addressing maternal-fetal attachment and parental anxiety and depression is also an urgent priority. In a randomised-trial context, such trials may allocate parents to different forms of support, to determine which have the greatest benefit with the least financial cost. Importantly, consistency in nomenclature and in data collection across all future trials (randomised and non-randomised) may be facilitated by a core outcomes data set for stillbirth research. All future trials should assess short- and longer-term psychosocial outcomes for parents and families, alongside economic costs of interventions.

Modulatory effect of intravenous immunoglobulin on Th17/Treg cell balance in women with unexplained recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) is a growing problem worldwide. In a majority of cases, the cause remains unknown but there is increasing evidence that immunologic factors play an important role. Intravenous immunoglobulin (IVIg) therapy has been proposed to have immune modulatory effects and therefore been applicable for the treatment of patients with RSA. Although its efficacy is still controversial, several recent studies suggest that IVIg treatment may improve pregnancy outcomes. CD4⁺ T cells and their related cytokines play an important role in maternal-fetal immune regulation, and an imbalance of Th17/Treg cell ratio has been proposed as a cause for RSA. We review the scientific evidence supporting a modulatory effect of IVIg on Th17/Treg cell balance and discuss the potential mechanisms how IVIg might enhance Treg cells function. We propose that correction of Th17/Treg cell dysregulation could be one of the mechanisms that can explain the positive therapeutic effects of IVIg therapy. Consequently, selecting patients with abnormal Th17/Treg cell ratios could increase the success of IVIg therapy.

A comparison of effectiveness among frequent treatments of recurrent spontaneous abortion: A Bayesian network meta-analysis

OBJECTIVE

A comprehensive network meta-analysis was designed to clarify contradictions and offer valuable clinical guidance in the treatment of recurrent spontaneous abortion (RSA).

METHOD

The included clinical trials were selected from the relevant medical journal databases and screened. Treatments were ranked by the surface under the cumulative ranking curve. Heat plots were constructed to analyze the inconsistency between direct data and network results, and adjusted funnel plots were constructed to assess publication bias.

RESULTS

Forty-nine randomized controlled trials involving a total of 8496 RSA patients were selected. With placebo as control, corticosteroid plus low dose aspirin (LDA) plus unfractionated heparin (UFH), granulocyte colony-stimulating factor (G-CSF) alone, and LDA plus low molecular weight heparin (LMWH) all demonstrated effectiveness in increasing successful live birth rates and reducing the incidences of miscarriage. However, no treatment was demonstrably superior to placebo in terms of pregnancy success. For all 3 endpoints (live birth, abortion and success pregnancy), the adjusted funnel plots were symmetric to zero and indicated no publication bias. In terms of live birth and abortion rates, no treatment outperformed placebo in patients with antiphospholipid syndrome.

CONCLUSION

In consideration of live birth and abortion rates, corticosteroid plus LDA plus UFH appeared to be the optimum treatment strategy; G-CSF was second, followed by LDA with LMWH, LDA plus LMWH plus intravenous immunoglobulin, corticosteroid with LDA and others. Subgroup analysis demonstrated no benefit of antithrombotic therapy in patients with antiphospholipid syndrome.

Treatment efficacy for idiopathic recurrent pregnancy loss - a systematic review and meta-analyses

INTRODUCTION

Medical treatment of women with idiopathic recurrent pregnancy loss is controversial. The objective was to assess the effects of different treatments on live birth rates and complications in women with unexplained recurrent pregnancy loss.

MATERIAL AND METHODS

We searched MEDLINE, Embase and the Cochrane Library, and identified 1415 publications. This systematic review included 21 randomized controlled trials regarding acetylsalicylic acid, low-molecular-weight heparin, progesterone, intravenous immunoglobulin or leukocyte immune therapy in women with three or more consecutive miscarriages of unknown cause. The study quality was assessed and data was extracted independently by at least two authors.

RESULTS

No significant difference in live birth rate was found when acetylsalicylic acid was compared with low-molecular-weight heparin or with placebo. Meta-analyses of low-molecular-weight heparin vs. control found no significant differences in live birth rate [risk ratio (RR) 1.47, 95% CI 0.83-2.61]. Treatment with progesterone starting in the luteal phase seemed effective in increasing live birth rate (RR 1.18, 95% CI 1.09-1.27) but not when started after conception. Intravenous immunoglobulin showed no effect on live birth rate compared with placebo (RR 1.07, 95% CI 0.91-1.26). Paternal immunization compared with autologous immunization showed a significant difference in outcome (RR 1.8, 95% CI 1.34-2.41), although the studies were small and at high risk of bias.

CONCLUSION

The literature does not allow advice on any specific treatment for idiopathic recurrent pregnancy loss, with the exception of progesterone starting from ovulation. We suggest that any treatment for recurrent pregnancy loss should be used within the context of a randomized controlled trial.

Recurrent pregnancy loss: current perspectives

Recurrent pregnancy loss is an important reproductive health issue, affecting 2%–5% of couples. Common established causes include uterine anomalies, antiphospholipid syndrome, hormonal and metabolic disorders, and cytogenetic abnormalities. Other etiologies have been proposed but are still considered controversial, such as chronic endometritis, inherited thrombophilias, luteal phase deficiency, and high sperm DNA fragmentation levels. Over the years, evidence-based treatments such as surgical correction of uterine anomalies or aspirin and heparin for antiphospholipid syndrome have improved the outcomes for couples with recurrent pregnancy loss. However, almost half of the cases remain unexplained and are empirically treated using progesterone supplementation, anticoagulation, and/or immunomodulatory treatments. Regardless of the cause, the long-term prognosis of couples with recurrent pregnancy loss is good, and most eventually achieve a healthy live birth. However, multiple pregnancy losses can have a significant psychological toll on affected couples, and many efforts are being made to improve treatments and decrease the time needed to achieve a successful pregnancy. This article reviews the established and controversial etiologies, and the recommended therapeutic strategies, with a special focus on unexplained recurrent pregnancy losses and the empiric treatments used nowadays. It also discusses the current role of preimplantation genetic testing in the management of recurrent pregnancy loss.

Intravenous immunoglobulin G in women with reproductive failure: The Korean Society for Reproductive Immunology practice guidelines

The task force of the Korean Society for Reproductive Immunology recommends intravenous immunoglobulin G treatment in women with reproductive failure, including recurrent pregnancy loss and/or repeated implantation failure, who show cellular immune factors such as abnormal natural killer cell levels, natural killer cell cytotoxicity, and/or type 1 T helper immunity.

Transcervical embryoscopic and cytogenetic findings reveal distinctive differences in primary and secondary recurrent pregnancy loss

OBJECTIVE

To assess the cytogenetic and embryoscopic characteristics of primary and secondary recurrent pregnancy loss.

DESIGN

Clinical prospective descriptive study.

SETTING

Tertiary care center.

PATIENT(S)

Nine hundred and eighty-four women affected by first-trimester pregnancy loss; 145 patients with recurrent pregnancy loss (RPL) and 839 patients with nonrecurrent pregnancy loss as controls.

INTERVENTION(S)

Transcervical embryoscopic examination of the embryo before uterine evacuation, and cytogenetic analysis of the chorionic villi by standard G-banding cytogenetic techniques.

MAIN OUTCOME MEASURE(S)

Aneuploidy frequency in the primary and secondary RPL group and the nonrecurrent pregnancy loss (non-RPL) control group.

RESULT(S)

Patients with RPL showed statistically significantly fewer aneuploid pregnancy losses (odds ratio [OR] 0.596; 95% confidence interval [CI], 0.40-0.88). Primary RPL was associated with lower aneuploidy rates compared with the non-RPL group (OR 0.423; 95% CI, 0.27-0.66) while secondary RPL was not (OR 1.414; 95% CI, 0.67-2.99). Patients with primary RPL had statistically significantly more morphologically normal embryos compared with non-RPL and secondary RPL.

CONCLUSION(S)

Patients' embryos after primary and secondary RPL show distinctive differences in aneuploidy and morphologic defect rates. These findings suggest different treatment approaches for the patients with primary and secondary RPL.

Recurrent pregnancy loss: what is the impact of consecutive versus non-consecutive losses?

STUDY QUESTION

Is there a different prognostic impact for consecutive and non-consecutive early pregnancy losses in women with secondary recurrent pregnancy loss (RPL)?

SUMMARY ANSWER

Only consecutive early pregnancy losses after the last birth have a statistically significant negative prognostic impact in women with secondary RPL.

WHAT IS KNOWN ALREADY

The risk of a new pregnancy loss increases with the number of previous pregnancy losses in patients with RPL. Second trimester losses seem to exhibit a stronger negative impact than early losses. It is unknown whether the sequence of pregnancy losses plays a role for the prognosis in patients with a prior birth.

STUDY DESIGN, SIZE, DURATION

This retrospective cohort study of pregnancy outcome in patients with unexplained secondary RPL included in three previously published, Danish double-blinded placebo-controlled trials of intravenous immunoglobulin (IvIg) conducted from 1991 to 2014. No other treatments were given. Patients with documented explained pregnancy losses (ectopic pregnancies and aneuploid miscarriages) were excluded.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Of the 168 patients included in the trials, 127 had secondary RPL and experienced a subsequent live birth or unexplained pregnancy loss in the first pregnancy after giving informed consent to participate in the trials (the index pregnancy). Data analyzed by multivariate analysis included the independent variables age, the number of early pregnancy losses before and after the last birth, respectively and a second trimester pregnancy loss before or after the last birth, respectively. The outcome variable was unexplained loss in the index pregnancy.

MAIN RESULTS AND THE ROLE OF CHANCE

In patients with secondary RPL, both a late and each early loss before the last birth did not significantly influence the risk of a new pregnancy loss in the index pregnancy: incidence rate ratio (IRR) 1.31 (95% CI 0.62-2.77) and IRR 0.88 (95% CI 0.70-1.11), respectively. In contrast, the impact on risk of pregnancy loss conferred by a late and by each early pregnancy loss occurring after the birth was significant: IRR 2.15 (95% CI 1.57-2.94, P < 0.0001) and IRR 1.14 (95% CI 1.04-1.24, P = 0.002), respectively.

LIMITATIONS, REASONS FOR CAUTION

Of the patients, 48% were treated with IvIg, which could influence the results. However, allocation to IvIg was random and prognostic variables were equally distributed in IvIg and placebo-treated patients.

WIDER IMPLICATIONS OF THE FINDINGS

A birth in women with secondary RPL eradicates the negative prognostic impact of previous pregnancy losses and this finding is important for our understanding of the pathogenesis. It indicates that only consecutive pregnancy losses should count in the definition of RPL.

STUDY FUNDING/COMPETING INTERESTS

There was no particular funding for this study. The authors declare that there is no conflict of interest.

TRIAL REGISTRATION NUMBER

Not applicable for two of the included randomized controlled trials. For the last trial: Clinical.Gov NCT00722475.

Intravenous immune globulin and thromboembolic adverse events: A systematic review and meta-analysis of RCTs

Prior case reports and observational studies indicate that intravenous immune globulin (IVIg) products may cause thromboembolic events (TEEs), leading the FDA to require a boxed warning in 2013. The effect of IVIg treatment on the risk of serious TEEs (acute myocardial infarction, ischemic stroke, or venous thromboembolism) was assessed using adverse event data reported in randomized controlled trials (RCTs) of IVIg. RCTs of IVIg in adult patients from 1995 to 2015 were identified from Pubmed, Embase, ClinicalTrials.Gov, and two large prior reviews of IVIg's therapeutic applications. Trials at high risk of detection or reporting bias for serious adverse events were excluded. 31 RCTs with a total of 4,129 participants (2,318 IVIg-treated, 1,811 control) were eligible for quantitative synthesis. No evidence was found of increased TEE risk among IVIg-treated patients compared with control patients (odds ratio = 1.10, 95% CI: 0.44, 2.88; risk difference = 0.0%, 95% CI: -0.7%, 0.7%, I(2)  = 0%). No significant increase in risk was found when arterial and venous TEEs were analyzed as separate endpoints. Trial publications provided little specific information concerning the methods used to ascertain potential adverse events. Care should be taken in extrapolating the results to patients with higher baseline risks of TEE. Am. J. Hematol. 91:594-605, 2016. © 2016 Wiley Periodicals, Inc.

Immunogenetic contributions to recurrent pregnancy loss

While sporadic pregnancy loss is common, occurring in 15 % of pregnancies, recurrent pregnancy loss (RPL) impacts approximately 5 % of couples. Though multiple causes are known (including structural, hormonal, infectious, autoimmune, and thrombophilic causes), after evaluation, roughly half of all cases remain unexplained. The idiopathic RPL cases pose a challenging therapeutic dilemma in addition to incurring much physical and emotional morbidity. Immunogenetic causes have been postulated to contribute to these cases of RPL. Natural Killer cell, T cell expression pattern changes in the endometrium have both been shown in patients with RPL. Human leukocyte antigen (HLA) and cytokine allelic variations have also been studied as etiologies for RPL. Some of the results have been promising, however the studies are small and have not yet put forth outcomes that would change our current diagnosis and management of RPL. Larger database studies are needed with stricter control criteria before reasonable conclusions can be drawn.

Innate Immune System at the Maternal-Fetal Interface: Mechanisms of Disease and Targets of Therapy in Pregnancy Syndromes

The maternal-fetal interface is an immunologically unique site that allows the tolerance to the allogenic fetus and maintains host defense against possible pathogens. Balanced immune responses are required for the maintenance of successful pregnancy. It has been demonstrated that innate immune disturbances may be responsible for some adverse pregnancy outcomes such as preeclampsia (PE); hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome; intrauterine growth restriction (IUGR); and recurrent spontaneous abortion (RSA). Observational studies suggest that immunomodulatory treatments in pregnancy-specific complications may improve both the hematological/biochemical features in the mother and the perinatal outcomes. The following review will discuss how recent and relevant findings in the field of the innate immunity have advanced our understanding of the role of inflammation and innate immune system in the pathogenesis of pregnancy failure and will discuss the therapeutic outcomes of the existing studies and clinical trials in light of these new insights.

Consecutive successful pregnancies subsequent to intravenous immunoglobulin therapy in a patient with recurrent spontaneous miscarriage

Background

Recurrent spontaneous miscarriage (RSM) has a multifactorial etiology, mainly due to karyotype abnormalities including balanced translocation, anatomical uterine disorders, and immunological factors, although in 50%–60% the etiology is unexplained. The treatment of RSM remains challenging, and the role of intravenous immunoglobulin (IVIG) in RSM is controversial.

Case report

Mrs HM, 37 years old, obstetric summary: P0+1+13+1, a known case of hypothyroidism/polycystic ovary syndrome, married to an unrelated 47-year-old man, presented to our RSM clinic in early January 2014 for investigation and treatment. She has had multiple failed in vitro fertilization trials and 13 first-trimester missed miscarriages terminating at 6–7 weeks, all without IVIG therapy. Her tenth pregnancy was spontaneous, managed in London, UK, with multiple supportive therapy and courses of IVIG starting from the third to the 30th week of pregnancy. The pregnancy ended at 36 weeks of gestation with a cesarean section and a live girl baby was delivered. Mrs HM had balanced translocation, 46XX t (7:11) (p10:q10). Preimplantation genetic diagnosis/intracytoplasmic sperm injection/in vitro fertilization was performed with embryo transfer on May 29, 2014, and resulted in a successful pregnancy. She was commenced immediately on metformin, luteal support, and IVIG therapy, started at 6 weeks of gestation and at monthly intervals until 30 weeks of gestation, and also received additional therapy. The pregnancy was monitored with ultrasound, progressed uneventfully until admission at 35 weeks of gestation, with mildly elevated liver enzymes and suspected fetal growth restriction. She was managed conservatively, and in the light of nonreassuring fetal status, a live female infant weighing 2.29 kg was delivered by emergency cesarean section on January 14, 2015, with an Apgar score of 8 and 9 and mild respiratory distress, and was admitted to the Special Care Baby Unit for intensive therapy. The mother and baby made satisfactory progress and were discharged on January 24, 2015.

Conclusion

Two consecutive successful pregnancies in Mrs HM with multiple causes of RSM treated with other medications and IVIG strongly suggest that IVIG has a positive role in RSM.

The Effects of Intravenous Immunoglobulins in Women with Recurrent Miscarriages: A Systematic Review of Randomised Trials with Meta-Analyses and Trial Sequential Analyses Including Individual Patient Data

BACKGROUND

Immunological disturbances are hypothesised to play a role in recurrent miscarriage (RM) and therefore intravenous immunoglubulins (IVIg) have been tested in RM patients.

OBJECTIVES

The objectives were to investigate the benefits and harms of IVIg versus placebo, no intervention, or treatment as usual in women with RM.

SEARCH STRATEGY

We searched the published literature in all relevant databases.

SELECTION CRITERIA

Randomised trials investigating IVIg versus placebo, no intervention, or treatment as usual in women with RM.

DATA COLLECTION AND ANALYSIS

We undertook meta-analyses of aggregated data and individual patient data using a two-step approach, and we conducted bias domain assessments and trial sequential analyses to assess the risks of systematic and random errors.

MAIN RESULTS

We identified 11 randomised clinical trials. No significant difference in the frequency of no live birth was found when IVIg was compared with placebo or treatment as usual (RR 0.92, 95% CI 0.75-1.12, p = 0.42). Trial sequential analysis showed that the required information size of 1,008 participants was not obtained. IVIg compared with placebo seems to increase the risk of adverse events. Subgroup analysis suggests that women with RM after a birth (secondary RM) seemed most likely to obtain a potential beneficial effect of IVIg (RR for no live birth 0.77, 95%CI 0.58-1.02, p = 0.06), however, trial sequential analysis showed that insufficient information is presently accrued.

CONCLUSION

We cannot recommend or refute IVIg in women with RM. IVIg should therefore be assessed in further randomised clinical trials with positive outcomes before any clinical use is considered.

Role of inflammatory mediators in patients with recurrent pregnancy loss

OBJECTIVE

To examine interleukin-12 (IL-12), IL-18, IFN-γ, intracellular adhesion molecule-1 (ICAM-1), leukemia inhibitory factor (LIF), and migration inhibitory factor (MIF) levels in precisely-timed blood and endometrial tissue samples from women with idiopathic recurrent pregnancy loss (RPL).

DESIGN

Case-control study.

SETTING

University hospital.

PATIENT(S)

Twenty-one women with RPL and 20 women with proven fertility (controls).

INTERVENTION(S)

Primary endometrial cells and blood samples during the midsecretory phase (days 19-23).

MAIN OUTCOME MEASURE(S)

Detection of IL-12, IL-18, IFN-γ, ICAM-1, LIF, and MIF via enzyme-linked immunosorbent assay in both blood and endometrial tissue samples.

RESULT(S)

The blood and tissue levels of IL-12, IL-18, and IFN-γ were statistically significantly higher, and the blood and tissue levels of LIF and MIF were statistically significantly lower in patients with RPL. Only the level of tissue ICAM-1 was higher in patients with RPL. There was a strong correlation between blood and tissue level measurements of IL-12, IL-18, LIF, and MIF.

CONCLUSION(S)

Our findings support the hypothesis that inflammatory processes may contribute to pregnancy loss, possibly through their role in implantation. We found that blood and tissue levels of IL-18, LIF, and MIF, and tissue levels of IL-12, IFN-γ, and ICAM-1 have statistically significant prognostic relevance.

Effects of polyvalent immunoglobulins in patients with recurrent pregnancy loss and antibodies to the choriocarcinoma cell line JEG-3

OBJECTIVE

The benefit of polyvalent immunoglobulins (IVIG) for patients with recurrent pregnancy loss (RPL) is controversially discussed. Anti-trophoblast antibodies as an expression of immune pathology have been associated with RPL. We investigated whether the antibody activity against the choriocarcinoma cell line JEG-3 in RPL patients is influenced in vitro by IVIG.

STUDY DESIGN

Sera of 110 unexplained RPL patients with positive anti-JEG-3 antibodies were coincubated with IVIG in different concentrations (10mg/ml, 20mg/ml, 40mg/ml). Coincubation with human albumin in identical concentrations served as control. Anti-JEG-3 reactivity was measured by using flow cytometry in comparisons with two in-house standards antibody probes of low and high reactivity as described before. Anti-JEG-3 reactivity above the 95% confidence interval of controls was defined as positive.

RESULTS

Incubating RPL sera with 10mg/ml IVIG significantly decreased anti-JEG-3 activity (p<0.001). Increasing IVIG concentration to 40mg/ml resulted in a slightly additionally reduction (p=0.42). In contrast, coincubation with albumin in identically concentrations did not affect anti-JEG-3 activity (p>0.40).

CONCLUSION

Coincubation with IVIG in vitro leads to a significant suppression of anti-JEG-3 activity in the sera of RPL patients.