Gonadotropin-releasing hormone agonist downregulation combined with hormone replacement therapy improves the reproductive outcome in frozen-thawed embryo transfer cycles for patients of advanced reproductive age with idiopathic recurrent implantation failure.

BACKGROUND: To determine whether gonadotropin-releasing hormone (GnRH) agonist downregulation combined with hormone replacement therapy (HRT) can improve the reproductive outcomes in frozen-thawed embryo transfer cycles for older patients (aged 36-43 years) with idiopathic recurrent implantation failure (RIF). METHODS: This retrospective cohort study involved 549 older patients undergoing their third cleavage-stage embryo or blastocyst transfer over a 5-year period (January 2015-December 2020) at Northwest Women's and Children's Hospital after in vitro fertilization/intracytoplasmic sperm injection cycles. Patients with known endometriosis or adenomyosis were excluded from the study. The patients were divided into three groups according to the endometrial preparation protocol: the natural cycle (NC) group (n = 65), the HRT group (n = 194), and the GnRH agonist downregulation combined with HRT cycle (GnRH agonist-HRT) group (n = 290). The primary outcome was the live birth rate, and the secondary outcomes were the clinical pregnancy, miscarriage, and ongoing pregnancy rates. RESULTS: The live birth rate in the GnRH agonist-HRT group (36.55%) was higher than that in the HRT group (22.16%) and NC group (16.92%) (P < 0.0001). Similarly, a logistic regression model adjusting for potential confounders showed that the live birth rate was higher in the GnRH agonist-HRT group than in the HRT group (odds ratio, 0.594; 95% confidence interval, 0.381-0.926; P = 0.021) and NC group (odds ratio, 0.380; 95% confidence interval, 0.181-0.796; P = 0.010). CONCLUSIONS: The GnRH agonist-HRT protocol improves the live birth rate in frozen-thawed embryo transfer cycles for patients of advanced reproductive age with RIF. We hypothesize that the GnRH agonist-HRT protocol enhances implantation-related factors and promotes optimal endometrial receptivity, leading to an improved live birth rate. These findings are also useful for further investigating the underlying mechanism of the GnRH agonist-HRT protocol in improving the reproductive outcomes for patients of advanced reproductive age with RIF. TRIAL REGISTRATION: This research protocol was approved by the hospital institutional ethics committee (No. 2021002).

Preconceptional evaluation of women with recurrent pregnancy loss: the additional value of assessing vascular and metabolic status.

BACKGROUND: A majority of recurrent pregnancy loss cases (RPL) remains unexplained. We hypothesized that complications in vascular and metabolic status may guide towards underlying problems that also predispose to RPL and that the number of pregnancy losses is related. METHODS: A retrospective study in 123 women with either a history of low-order RPL (2-3 pregnancy losses) or high-order RPL (≥ 4 pregnancy losses) and 20 women with a history of uncomplicated pregnancy (controls) was performed. Vascular status was assessed by measuring hemodynamic parameters, determining abnormal parameters and analyzing their contribution to the circulatory risk profile (CRP). In a similar way, metabolic status was assessed. Metabolic parameters were measured, used to determine abnormal parameters and analyzed for their contribution to the metabolic syndrome (MetS). RESULTS: No major differences were observed in vascular or metabolic parameters between women with RPL and controls. There was no relation with the number of pregnancy losses. However, when analyzing the presence of abnormal constituents, more than 80% of women with RPL had at least one abnormal constituent of the CRP. While only 27% had one or more abnormal constituent of the MetS. CONCLUSIONS: The presence of abnormal circulatory factors prior to pregnancy, and to lesser extent constituents of the metabolic syndrome, may predispose to RPL and offer new insights to its pathophysiology.

DNA Methylation and Recurrent Pregnancy Loss: A Mysterious Compass?

Recurrent pregnancy loss (RPL) is a common and severe pathological pregnancy, whose pathogenesis is not fully understood. With the development of epigenetics, the study of DNA methylation, provides a new perspective on the pathogenesis and therapy of RPL. The abnormal DNA methylation of imprinted genes, placenta-specific genes, immune-related genes and sperm DNA may, directly or indirectly, affect embryo implantation, growth and development, leading to the occurrence of RPL. In addition, the unique immune tolerogenic microenvironment formed at the maternal-fetal interface has an irreplaceable effect on the maintenance of pregnancy. In view of these, changes in the cellular components of the maternal-fetal immune microenvironment and the regulation of DNA methylation have attracted a lot of research interest. This review summarizes the research progress of DNA methylation involved in the occurrence of RPL and the regulation of the maternal-fetal immune microenvironment. The review provides insights into the personalized diagnosis and treatment of RPL.

FPR2 serves a role in recurrent spontaneous abortion by regulating trophoblast function via the PI3K/AKT signaling pathway.

Recurrent spontaneous abortion (RSA) effects both the physical and mental health of women of reproductive age. Trophoblast dysfunction may result in RSA due to shallow placental implantation. The mechanisms underlying formyl peptide receptor 2 (FPR2) on the biological functions of trophoblasts remain to be elucidated. The present study aimed to explore the potential functions of FPR2, a G protein­coupled receptor, in placental trophoblasts. The location and expression levels of FPR2 in the villi tissue of patients with RSA were detected using immunohistochemical staining, reverse transcription­quantitative PCR and western blotting. Following the transfection of small interfering RNA targeting FPR2 in HTR­8/SVneo cells, a Cell Counting Kit­8 assay was used to determine the levels of cell viability. Flow cytometry was used to examine the levels of cell apoptosis and gap closure and Transwell assays were carried out to evaluate the levels of cell migration and invasion. A tube formation assay was performed to detect the levels of capillary­like structure formation. Western blotting was used to detect the expression levels of proteins in the associated signaling pathways. The expression of FPR2 was present in villi trophoblasts and was markedly increased in patients with RSA. The levels of trophoblast invasion, migration and tube formation were markedly increased following FPR2 knockdown, whereas the levels of apoptosis were markedly decreased. In addition, FPR2 knockdown caused an increase in the phosphorylation levels of AKT and PI3K. Thus, FPR2 may be involved in the regulation of trophoblast function via the PI3K/AKT signaling pathway. The results of the present study provided a theoretical basis for the use of FPR2 as a target for the treatment of trophoblast­associated diseases, such as RSA.

Treatment following hysteroscopy and endometrial diagnostic biopsy increases the chance for live birth in women with chronic endometritis.

PROBLEM: Repeated implantation failure and recurrent pregnancy loss are associated with chronic endometritis, a persistent endometrial inflammation. Its diagnosis and treatment may increase pregnancy and live birth rates. The aim of this study was to assess the effectiveness of endometrial diagnostic biopsy and subsequent antibiotic treatment in cases of chronic endometritis on reproductive outcomes over a long observation period. METHOD OF STUDY: We conducted a historical cohort study (2014-2018) at our University-based infertility center that included women (n = 108) with repeated implantation failure or recurrent pregnancy loss without known pathologies associated with either condition. Forty-one women underwent a hysteroscopy only (reference group); the remaining 67 women underwent, in addition to the hysteroscopy, an endometrial diagnostic biopsy with immunohistochemically staining for CD138 to detect plasma cells (biopsy group). If one or more plasma cells were detected, the women were treated with doxycycline 100 mg twice a day orally for 2 weeks. We performed stratified survival analysis (Kaplan-Meier) and Cox regression. RESULTS: The biopsy group had higher chances of pregnancy (hazard ratio 2.28; 95% confidence interval 1.23-4.24; p = .009) and of live birth (hazard ratio 2.76; 95% confidence interval 1.30-5.87; p = .008) compared with the reference group. In the sensitivity analysis, repeated implantation failure or recurrent pregnancy loss did not affect the outcome. CONCLUSION: Endometrial diagnostic biopsy followed by antibiotic treatment in case of chronic endometritis in women with repeated implantation failure or recurrent pregnancy loss may increase the chances for live birth.

LncRNA LINC01088 inhibits the function of trophoblast cells, activates the MAPK-signaling pathway and associates with recurrent pregnancy loss.

Long noncoding RNAs (lncRNAs) have been reported to be involved in various cellular processes and to participate in a variety of human diseases. Recently, increasing studies have reported that lncRNAs are related to many reproductive diseases, such as pathogenesis of recurrent pregnancy loss (RPL), preeclampsia (PE) and gestational diabetes mellitus (GDM). In this study, we aimed to investigate the effect of LINC01088 in trophoblast cells and its potential role in pathogenesis of RPL. LINC01088 was found to be upregulated in first-trimester chorionic villi tissues from RPL patients. Increased LINC01088 repressed proliferation, migration and invasion of trophoblast cells, and promoted apoptosis of trophoblast cells. Further exploration indicated that LINC01088 decreased the production of nitric oxide (NO) by binding and increasing Arginase-1 and decreasing eNOS protein levels. Importantly, JNK and p38 MAPK-signaling pathways were active after overexpression of LINC01088. In conclusion, our studies demonstrated that LINC01088 plays an important role in the pathogenesis of RPL, and is a potential therapeutic target for the treatment of RPL.

Proteomic and functional analysis of proteins related to embryonic development of decidua in patients with recurrent pregnancy loss†.

Recurrent pregnancy loss (RPL) is defined as the loss of two or more consecutive pregnancies before the 20 weeks of gestation. RPL affects about 1-2% of couples trying to conceive; however, the mechanisms leading to this complication are largely unknown. Our previous studies using comparative proteomics identified 314 differentially expressed proteins (DEPs) in the placental villous. In this study, we identified 5479 proteins from a total of 34 157 peptides in decidua of patients with early RPL (data are available via ProteomeXchange with identifier PXD023849). Further analysis identified 311 DEPs in the decidua tissue; and 159 proteins were highly expressed, whereas 152 proteins were lowly expressed. These 311 proteins were further analyzed by using Ingenuity Pathway Analysis. The results suggested that 50 DEPs played important roles in the embryonic development. Upstream analysis of these DEPs revealed that angiotensinogen was the most important upstream regulator. Furthermore, protein-protein interaction analysis of the embryonic development DEPs from the placental villous and decidua was performed in the STRING database. This study identified several proteins specifically associated with embryonic development in decidua of patients with early RPL. Therefore, these results provide new insights into potential biological mechanisms, which may ultimately inform RPL.

Obesity Challenge Drives Distinct Maternal Immune Response Changes in Normal Pregnant and Abortion-Prone Mouse Models.

Obesity is prevalent among women of reproductive age and is associated with increased risk of developing multiple pregnancy disorders. Pregnancy must induce immune tolerance to avoid fetal rejection, while obesity can cause chronic inflammation through activating the immune system. Impaired maternal immuno-tolerance leads to pregnancy failure, such as recurrent spontaneous abortion (RSA), one of the most common complications during early pregnancy. How does maternal immune response change under obesity stress in normal pregnancy and RSA? In turn, is obesity affected by different gestational statuses? Limited information is presently available now. Our study investigated pregnancy outcomes and maternal immune responses in two murine models (normal pregnancy and spontaneous abortion models) after obesity challenge with a high-fat diet (HFD). Abortion-prone mice fed HFD had significantly higher weight gains during pregnancy than normal pregnant mice with HFD feeding. Nonetheless, the embryo implantation and resorption rates were comparable between HFD and normal chow diet (NCD)-fed mice in each model. Evaluation of immune cell subsets showed HFD-induced obesity drove the upregulation of activated NK cell-activating receptor (NKp46)+ NK cells and pro-inflammatory macrophages (MHCIIhigh Mφ) as well as CD4+ and CD8+ T cells in the normal pregnancy group. However, in the abortion-prone group, relative more immature NK cells with decreased activity phenotypes were found in obese mice. Moreover, there were increased DCreg (CD11bhigh DC) cells and decreased CD4+ and CD8+ T cells detected in the HFD abortion-prone mice relative to those fed the NCD diet. Our findings reveal how pregnancy obesity and maternal immune regulation are mutually influenced. It is worth noting that the abortion-prone model where active maternal immune status was intensified by obesity, in turn stimulated an overcompensation response, leading to an over-tolerized immune status, and predisposing to potential risks of perinatal complications.

Miscarriage matters: the epidemiological, physical, psychological, and economic costs of early pregnancy loss.

Miscarriage is generally defined as the loss of a pregnancy before viability. An estimated 23 million miscarriages occur every year worldwide, translating to 44 pregnancy losses each minute. The pooled risk of miscarriage is 15·3% (95% CI 12·5-18·7%) of all recognised pregnancies. The population prevalence of women who have had one miscarriage is 10·8% (10·3-11·4%), two miscarriages is 1·9% (1·8-2·1%), and three or more miscarriages is 0·7% (0·5-0·8%). Risk factors for miscarriage include very young or older female age (younger than 20 years and older than 35 years), older male age (older than 40 years), very low or very high body-mass index, Black ethnicity, previous miscarriages, smoking, alcohol, stress, working night shifts, air pollution, and exposure to pesticides. The consequences of miscarriage are both physical, such as bleeding or infection, and psychological. Psychological consequences include increases in the risk of anxiety, depression, post-traumatic stress disorder, and suicide. Miscarriage, and especially recurrent miscarriage, is also a sentinel risk marker for obstetric complications, including preterm birth, fetal growth restriction, placental abruption, and stillbirth in future pregnancies, and a predictor of longer-term health problems, such as cardiovascular disease and venous thromboembolism. The costs of miscarriage affect individuals, health-care systems, and society. The short-term national economic cost of miscarriage is estimated to be £471 million per year in the UK. As recurrent miscarriage is a sentinel marker for various obstetric risks in future pregnancies, women should receive care in preconception and obstetric clinics specialising in patients at high risk. As psychological morbidity is common after pregnancy loss, effective screening instruments and treatment options for mental health consequences of miscarriage need to be available. We recommend that miscarriage data are gathered and reported to facilitate comparison of rates among countries, to accelerate research, and to improve patient care and policy development.

Role of the sperm, oocyte, and embryo in recurrent pregnancy loss.

Disorders affecting the sperm, oocyte, or embryo may cause a significant fraction of spontaneous miscarriages and cases of recurrent pregnancy loss (RPL). Altered chromosomal integrity of sperm and oocytes, which is highly dependent of the age of the mother, represents a major cause of miscarriage and in turn RPL. Avoiding transfers of abnormal embryos is possible with preimplantation genetic testing for aneuploidies. Chromosomal anomalies may also be caused by structural rearrangements of one or several chromosomes in either parents, a finding encountered in 12% of couples with RPL, including in those who have had one or several healthy babies. More than 40% of these chromosomal rearrangements are identifiable on regular karyotypes. When abnormal findings are made, preimplantation genetic testing for monogenic disorders allows selection of disease-free embryos. Finally, asymmetric inactivation of the X chromosome has been found more commonly in women with RPL, but no specific treatment is currently available.

Uterine factors in recurrent pregnancy losses.

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

Recurrent pregnancy losses, a lasting cause of infertility.

Recurrent pregnancy loss (RPL), defined as two to three spontaneous pregnancy terminations occurring before 12 weeks of gestation, affects approximately 1% of the general population. The causes may include congenital factors that originate with the quality of the gametes (sperm or oocyte) or the resulting embryo, or factors that originate within the uterus. Alterations of endometrial receptivity from endometriosis and/or endometritis, which are associated with impaired action of progesterone, have also been implicated in RPL. Finally, immunologic factors and thrombophilia, congenital and acquired, have also been suspected to cause RPL.

Endometrial causes of recurrent pregnancy losses: endometriosis, adenomyosis, and chronic endometritis.

Chronic inflammatory processes affecting the endometrium, as encountered in endometriosis, adenomyosis, and chronic endometritis, alter endometrial receptivity. These disorders are associated with early pregnancy losses and possibly recurrent pregnancy losses (RPL). In the cases of endometriosis, other factors associated with the disease also are susceptible of causing miscarriages and possibly RPL, such as an impact of intrapelvic inflammatory processes affecting the oocyte and embryo in case of natural conception. Conversely these latter effects obviously are bypassed in case of assisted reproductive technology. Chronic inflammation of the endometrium in the condition known as chronic endometritis also causes early pregnancy losses and RPL with beneficial effects achieved when specific treatment is undertaken.

Severe metabolic disorders coexisting with Werner syndrome: a case report.

Werner syndrome, also called adult progeria, is a heritable autosomal recessive human disorder characterized by the premature onset of numerous age-related diseases including juvenile cataracts, dyslipidemia, diabetes mellitus (DM), osteoporosis, atherosclerosis, and cancer. Werner syndrome is a segmental progeroid syndrome whose presentation resembles accelerated aging. The most common causes of death for WS patients are atherosclerosis and cancer. A 40-year-old female presented with short stature, bird-like facies, canities with alopecia, scleroderma-like skin changes, and non-healing foot ulcers. The patient reported a history of delayed puberty, abortion, hypertriglyceridemia, and juvenile cataracts. A clinical diagnosis of WS was made and subsequently confirmed. We discovered two WRN gene mutations in the patient, Variant 1 was the most common WRN mutation, nonsense mutation (c.1105C>T:p.R369Ter) in exon 9, which caused a premature termination codon (PTC) at position 369. Variant 2 was a frameshift mutation (c.1134delA:p.E379KfsTer5) in exon 9, which caused a PTC at position 383 and has no published reports describing. Patients with WS can show a wide variety of clinical and biological manifestations in endocrine-metabolic systems (DM, thyroid dysfunction, and hyperlipidemia). Doctors must be cognizant of early manifestations of WS and treatment options.

Role of Slit2 upregulation in recurrent miscarriage through regulation of stromal decidualization.

INTRODUCTION: Knockout mouse model has shown a relationship between Slit2/Robo1 signalling and altered fertility. Altered expression by endometrial epithelium and trophoblast and is associated with the pathogenesis of pregnancy complications but few studies have investigated the expression of decidual Slit2 in miscarriage. METHODS: Expression profiles of Slit2 and Robo1 were measured in human endometrial tissues during the menstrual cycle phases (n = 30), in decidua tissues from recurrent miscarriage (n = 20) and healthy control (n = 20) at 6-8 weeks of gestation. The hormonal regulation of Slit2/Robo1 expression and the role of Slit2/Robo1 signalling in decidualization was investigated in vitro, along with its effects on ß-catenin and MET expression. RESULTS: In human endometrium, Slit2 and Robo1 protein expression in stromal cells were decreased between the late-proliferative and early-secretory phase. In recurrent miscarriage patients, decidual expression Slit2 was increased and associated with lower expression of E-cadherin and higher level vimentin compared to controls. In vitro, the expression of Slit2 was downregulated by cAMP and progesterone in hESCs. Upregulation of Slit2 resulted in inhibition of cell decidualization and ß-catenin translocation to nucleus. DISCUSSION: This study indicates a functional role for Slit2 in endometrial stromal cell decidualization and the pathogenesis of recurrent miscarriage. Aberrant Increase in Slit2 expression may impairs decidualization of endometrial stromal cells leading to recurrent in recurrent miscarriage.

Cytokine imbalance at materno-embryonic interface as a potential immune mechanism for recurrent pregnancy loss.

Recurrent pregnancy loss (RPL) is a prominent reproductive disease that distresses about 2%-5% of couples. RPL is the loss of two or more successive spontaneous pregnancies prior to the 20th week of embryo development. The commencement of pregnancy necessitates implantation of the embryo into responsive maternal decidua synchronized with the process of placentation, decidual and myometrial trophoblast incursion as well as refashioning of spiral blood arteries of uterus. The collapse of any of the processes fundamental for pregnancy success may result into an array of pregnancy problems including spontaneous pregnancy loss. Endometrium of human female manufactures an extensive range of cytokines during the proliferative and secretory stage of the menstrual cycle. These endometrial cytokines are thought as major players for making the uterus ready for embryo implantation and placental development during pregnancy. Decidual cytokines regulate the invasion of trophoblast and remodeling of spiral arteries as well as take part in immune suppression to accomplish the pregnancy. Deterrence of maternal rejection of embryo needs a regulated milieu, which takes place essentially at the embryo-maternal interface and the tissues of the uterus. The reasons of RPL remain anonymous in a large number of cases that lead to difficulties in management and severe trauma in couples. Cytokine modulatory therapies have been shown promising for preventing RPL. Further study of novel factors is wanted to establish more effective RPL treatment protocols. The present study aims to review the outcome of cytokine breach at materno-embryonic interface and the efficacy of cytokine modulatory therapies in RPL.

The alteration and potential relationship of vaginal microbiota and chemokines for unexplained recurrent spontaneous abortion.

ABSTRACT: The diagnosis and treatment of unexplained recurrent spontaneous abortion (URSA) is an important and hot topic in the field of obstetrics and gynecology. During our clinical investigation (observation), we have found that URSA patients usually experience recurrent vaginitis or vaginal dysbacteriosis during periods of non-pregnancy, pregnancy, and post-abortion. However, there is no research on vaginal dysbacteriosis's influence on URSA. Using women with normal induced abortion as a control group, and using 16S rRNA sequencing, which helps to screen differentially expressed flora, this study discusses the relevance between differential bacteria at the genus level and the incidence of URSA. Another aim of this study is to determine whether certain pathogenic genera can cause an imbalance in immune tolerance of the maternal and fetal interface through regulatory chemokines, which leads to recurrent spontaneous abortion. This article has explored URSA pathogenesis from the perspective of differentially expressed vaginal flora, which has great theoretical significance for the early diagnosis and treatment of URSA.

The genetic architecture of sporadic and multiple consecutive miscarriage.

Miscarriage is a common, complex trait affecting ~15% of clinically confirmed pregnancies. Here we present the results of large-scale genetic association analyses with 69,054 cases from five different ancestries for sporadic miscarriage, 750 cases of European ancestry for multiple (≥3) consecutive miscarriage, and up to 359,469 female controls. We identify one genome-wide significant association (rs146350366, minor allele frequency (MAF) 1.2%, P = 3.2 × 10-8, odds ratio (OR) = 1.4) for sporadic miscarriage in our European ancestry meta-analysis and three genome-wide significant associations for multiple consecutive miscarriage (rs7859844, MAF = 6.4%, P = 1.3 × 10-8, OR = 1.7; rs143445068, MAF = 0.8%, P = 5.2 × 10-9, OR = 3.4; rs183453668, MAF = 0.5%, P = 2.8 × 10-8, OR = 3.8). We further investigate the genetic architecture of miscarriage with biobank-scale Mendelian randomization, heritability, and genetic correlation analyses. Our results show that miscarriage etiopathogenesis is partly driven by genetic variation potentially related to placental biology, and illustrate the utility of large-scale biobank data for understanding this pregnancy complication.

Estudio del entorno microbiológico uterino en reproducción asistida / Study of the microbiological environment uterine in assisted reproduction

CONTEXTO CLÍNICO: Los tratamientos de reproducción asistida son aquellos procedimientos realizados en situación de infertilidad y tienen como fin lograr un embarazo exitoso como resultado directo de la intervención. Se pueden clasificar en procedimientos de baja o alta complejidad según la técnica que se utilice. En aquellos de baja complejidad la fecundación se produce dentro del aparato reproductor femenino, mientras que los de alta complejidad la fecundación sucede en el laboratorio de embriología. Durante el año 2018 en Argentina se realizaron 12.222 tratamientos de reproducción asistida en 43 centros habilitados.1 En España durante el 2018 se realizaron 149.337 procedimientos relacionados a fertilización in vitro.2 En Estados Unidos, entre el 2006 y 2010 , el 8.7% de las mujeres realizaron al menos una consulta relacionada a infertilidad con el fin de lograr un embarazo. Los tratamientos de reproducción asistida no siempre son exitosos, y en la actualidad se definen situaciones tales como falla reiterada de implantación (FRI) como la "no consecución del embarazo en mujeres menores de 40 años, tras haber transferido al menos cuatro embriones de buena calidad, repartidos en un mínimo de tres transferencias (incluyendo tanto las realizadas en fresco como las de embriones criopreservados"; mientras que aborto recurrente se define como se define como dos o más pérdidas de embarazo clínico, no necesariamente consecutivos. TECNOLOGÍA: El análisis metagenómico de microbioma endometrial (EMMA; su sigla del inglés Endometrial Microbiome Metagenomic Analysis) es un test diagnóstico que utiliza técnica de secuenciación masiva proporcionando información del microbioma del tejido endometrial analizando el perfil microbiano completo. Puede diferenciar genes bacterianos de genes humanos presentes en ADN extraído de la muestra de tejido. El gen 16S ARN ribosomal, presente en todas las bacterias, presenta nueve regiones variables con una secuencia de ADN especifico de cada bacteria, lo que permite la identificación y cuantificación relativa de las bacterias presentes en la muestra. Esto podría determinar si el entorno microbiano del útero es óptimo para la implantación embrionaria. Las posibles indicaciones de este test son en aquellas pacientes con fallo recurrente de implantación y/o dentro del algoritmo de evaluación de infertilidad femenina. El informe incluye: porcentaje de lactobacilos, porcentaje de bacterias detectadas en la muestra endometrial en proporción significativa, clasificación del perfil de la microbiota endometrial (normal, anormal, disbiótico o muy baja biomasa), tratamiento antibiótico/probiótico sugerido y resultados del test ALICE, como se explicará a continuación. OBJETIVO: El objetivo del presente informe es evaluar la evidencia disponible acerca del desempeño diagnóstico, la eficacia, seguridad y aspectos relacionados a las políticas de cobertura del uso de estudio de microbiota endometrial EMMA y ALICE para pacientes en reproducción asistida con fallo recurrente de implantación embrionaria y/o aborto recurrente. MÉTODOS: Se realizó una búsqueda en las principales bases de datos bibliográficas, en buscadores genéricos de internet, y financiadores de salud. Se priorizó la inclusión de revisiones sistemáticas (RS), ensayos clínicos controlados aleatorizados (ECAs), evaluaciones de tecnologías sanitarias (ETS), evaluaciones económicas, guías de práctica clínica (GPC) y políticas de cobertura de diferentes sistemas de salud. RESULTADOS: Se incluyeron una RS de estudios observacionales, 2 estudios de cohorte, 4 GPC y 7 informes de políticas de cobertura de tecnología para indicación. CONCLUSIONES: Evidencia de muy baja calidad no permite establecer el beneficio asociado al uso del test de microbiota endometrial en reproducción asistida y en pacientes con falla reiterada de implantación y/o aborto recurrente. No se encontraron estudios comparativos que evalúen la utilidad clínica de los test de microbiota endometrial en pacientes que realizan tratamiento de fertilización asistida y presentan fallas reiteradas de la implantación y/o aborto recurrente. Las guías de práctica clínica relevadas no mencionan el estudio de la microbiota endometrial. Las políticas de coberturas consultadas provenientes de financiadores públicos y privados de Europa y Estados Unidos, así como los financiadores públicos de América Latina consultados, no mencionan a esta tecnología. No se encontraron estudios locales de costo-efectividad, impacto financiero u organizacional, por lo que el impacto es incierto en esta dimensión.

Unexplained repeated pregnancy loss is associated with altered perceptual and brain responses to men's body-odor.

Mammalian olfaction and reproduction are tightly linked, a link less explored in humans. Here, we asked whether human unexplained repeated pregnancy loss (uRPL) is associated with altered olfaction, and particularly altered olfactory responses to body-odor. We found that whereas most women with uRPL could identify the body-odor of their spouse, most control women could not. Moreover, women with uRPL rated the perceptual attributes of men's body-odor differently from controls. These pronounced differences were accompanied by an only modest albeit significant advantage in ordinary, non-body-odor-related olfaction in uRPL. Next, using structural and functional brain imaging, we found that in comparison to controls, most women with uRPL had smaller olfactory bulbs, yet increased hypothalamic response in association with men's body-odor. These findings combine to suggest altered olfactory perceptual and brain responses in women experiencing uRPL, particularly in relation to men's body-odor. Whether this link has any causal aspects to it remains to be explored.