The importance of the 'uterine factor' in recurrent pregnancy loss: a retrospective cohort study on women screened through 3D transvaginal ultrasound.

STUDY QUESTION: What is the prevalence of congenital and acquired anomalies of the uterus in women with recurrent pregnancy loss (RPL) of unknown etiology examined using 3D transvaginal ultrasound (US)? SUMMARY ANSWER: Depending on the adopted diagnostic criteria, the prevalence of partial septate uterus varies between 7% and 14% and a T-shaped uterus is 3% or 4%, while adenomyosis is 23%, at least one of type 0, type 1 or type 2 myoma is 4%, and at least one endometrial polyp is 4%. WHAT IS KNOWN ALREADY: ESHRE and the Royal College of Obstetricians and Gynaecologists guidelines on RPL recommend the adoption of the 3D transvaginal US to evaluate the 'uterine factor'. Nevertheless, there are no published studies reporting the prevalence of both congenital and acquired uterine anomalies as assessed by 3D transvaginal US and diagnosed according to the criteria proposed by the most authoritative panels of experts in a cohort of women with RPL. STUDY DESIGN, SIZE, DURATION: This was a retrospective cohort study including 442 women with at least two previous first-trimester spontaneous pregnancy losses (i.e. non-viable intrauterine pregnancies), who referred to the obstetrics and gynecology unit of two university hospitals between July 2020 and July 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS: Records of eligible women were reviewed. Women could be included in the study if: they were between 25 and 42 years old; they had no relevant comorbidities; they were not affected by infertility, and they had never undergone ART; they and their partner tested negative to a comprehensive RPL diagnostic work-up; and they had never undergone metroplasty, myomectomy, minimally invasive treatments for uterine fibroids or adenomyomectomy. Expert sonographers independently re-analyzed the stored 2- and 3D transvaginal US images of all included patients. Congenital uterine anomalies (CUAs) were reported according to the American Society for Reproductive Medicine (ASRM) 2021, the ESHRE/European Society for Gynaecological Endoscopy (ESGE) and the Congenital Uterine Malformation by Experts (CUME) criteria. Acquired uterine anomalies were reported according to the International Federation of Gynecology and Obstetrics (FIGO) and the Morphological Uterus Sonographic Assessment (MUSA) criteria. MAIN RESULTS AND THE ROLE OF CHANCE: The partial septate uterus was diagnosed in 60 (14%; 95% CI: 11-17%), 29 (7%; 95% CI: 5-9%), and 47 (11%; 95% CI: 8-14%) subjects, according to the ESHRE/ESGE, the ASRM 2021, and the CUME criteria, respectively. The T-shaped uterus was diagnosed in 19 women (4%; 95% CI: 3-7%) according to the ESHRE/ESGE criteria and in 13 women (3%; 95% CI: 2-5%) according to the CUME criteria. The borderline T-shaped uterus (diagnosed when two out of three CUME criteria for T-shaped uterus were met) was observed in 16 women (4%; 95% CI: 2-6%). At least one of FIGO type 0, type 1, or type 2 myoma was detected in 4% of included subjects (95% CI: 3-6%). Adenomyosis was detected in 100 women (23%; 95% CI: 19-27%) and was significantly more prevalent in women with primary RPL and in those with three or more pregnancy losses. At least one endometrial polyp was detected in 4% of enrolled women (95% CI: 3-7%). LIMITATIONS, REASONS FOR CAUTION: The absence of a control group prevented us from investigating the presence of an association between both congenital and acquired uterine anomalies and RPL. Second, the presence as well as the absence of both congenital and acquired uterine anomalies detected by 3D US was not confirmed by hysteroscopy. Finally, the results of the present study inevitably suffer from the intrinsic limitations of the adopted classification systems. WIDER IMPLICATIONS OF THE FINDINGS: The prevalence of CUAs in women with RPL varies depending on the classification system used. For reasons of clarity, the US reports should always state the name of the uterine anomaly as well as the adopted classification and diagnostic criteria. Adenomyosis seems to be associated with more severe forms of RPL. The prevalence rates estimated by our study as well as the replicability of the adopted diagnostic criteria provide a basis for the design and sample size calculation of prospective studies. STUDY FUNDING/COMPETING INTEREST(S): No specific funding was used. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Role of SLC7A11/xCT in Ovarian Cancer.

Ovarian cancer is one of the most dangerous gynecologic cancers worldwide and has a high fatality rate due to diagnosis at an advanced stage of the disease as well as a high recurrence rate due to the occurrence of chemotherapy resistance. In fact, chemoresistance weakens the therapeutic effects, worsening the outcome of this pathology. Solute Carrier Family 7 Member 11 (SLC7A11, also known as xCT) is the functional subunit of the Xc- system, an anionic L-cystine/L-glutamate antiporter expressed on the cell surface. SLC7A11 expression is significantly upregulated in several types of cancers in which it can inhibit ferroptosis and favor cancer cell proliferation, invasion and chemoresistance. SLC7A11 expression is also increased in ovarian cancer tissues, suggesting a possible role of this protein as a therapeutic target. In this review, we provide an overview of the current literature regarding the role of SLC7A11 in ovarian cancer to provide new insights on SLC7A11 modulation and evaluate the potential role of SLC7A11 as a therapeutic target.

First Trimester Placental Biomarkers for Pregnancy Outcomes.

The placenta plays a key role in several adverse obstetrical outcomes, such as preeclampsia, intrauterine growth restriction and gestational diabetes mellitus. The early identification of at-risk pregnancies could significantly improve the management, therapy and prognosis of these pregnancies, especially if these at-risk pregnancies are identified in the first trimester. The aim of this review was to summarize the possible biomarkers that can be used to diagnose early placental dysfunction and, consequently, at-risk pregnancies. We divided the biomarkers into proteins and non-proteins. Among the protein biomarkers, some are already used in clinical practice, such as the sFLT1/PLGF ratio or PAPP-A; others are not yet validated, such as HTRA1, Gal-3 and CD93. In the literature, many studies analyzed the role of several protein biomarkers, but their results are contrasting. On the other hand, some non-protein biomarkers, such as miR-125b, miR-518b and miR-628-3p, seem to be linked to an increased risk of complicated pregnancy. Thus, a first trimester heterogeneous biomarkers panel containing protein and non-protein biomarkers may be more appropriate to identify and discriminate several complications that can affect pregnancies.

Efficacy of ferric carboxymaltose for treatment of iron deficiency anemia diagnosed in the third trimester of pregnancy: A case-control study.

AIM: To assess the efficacy of intravenous ferric carboxymaltose (IV FCM) for the treatment of iron deficiency anemia (IDA) diagnosed de novo in the third trimester of pregnancy. METHODS: Case-control study conducted in pregnant women with IDA newly diagnosed in the third trimester of pregnancy. Women treated with a single IV FCM injection were included as cases and those who received daily 210 g of oral ferrous sulphate (FS) as controls. Controls were matched to cases in a 2:1 ratio by basal hemoglobin (Hb) concentration (±0.5 g/dl). RESULTS: A total of 35 cases and 70 controls were included in the study. The mean Hb concentration level significantly increased after iron treatment in both cases (from 9.3 ± 0.8 to 11.1 ± 0.8 g/dl, p < 0.0001) and controls (from 9.6 ± 0.9 to 10.9 ± 1 g/dl, p < 0.0001). The rate of women who exceeded the recommended threshold of 11 g/dl after treatment did not significantly differ between cases (63% (95%CI, 45%-79%)) and controls (56% (95%CI, 44%-68%)) (p = 0.48). Comparison of maternal and neonatal outcomes and adverse effects did not show any significant difference between groups. CONCLUSIONS: Our results suggest that IV FCM and oral FS can be considered equally effective in the treatment of IDA newly detected in the third trimester of pregnancy.

Diagnostic factors for recurrent pregnancy loss: an expanded workup.

PURPOSE: There is limited information on the risk factors for recurrent pregnancy loss (RPL). METHODS: In this study, a patient-based approach was used to investigate the possible involvement and relative relevance of a large number of diagnostic factors in 843 women with RPL who underwent an extensive diagnostic workup including 44 diagnostic factors divided into 7 major categories. RESULTS: The rates of abnormalities found were: (1) genital infections: 11.74%; (2) uterine anatomic defects: 23.72%; (3) endocrine disorders: 29.42%; (4) thrombophilias: 62%; (5) autoimmune abnormalities: 39.2%; (6) parental karyotype abnormalities 2.25%; (7) clinical factors: 87.78%. Six hundred and fifty-nine out of eight hundred and forty-three women (78.17%) had more than one abnormality. The mean number of pregnancy losses increased by increasing the number of the abnormalities found (r = 0.86949, P < 0.02). The factors associated with the highest mean number of pregnancy losses were cervical isthmic incompetence, anti-beta-2-glycoprotein-1 antibodies, unicornuate uterus, anti-prothrombin A antibodies, protein C deficiency, and lupus anticoagulant. The majority of the considered abnormalities had similar, non-significant prevalence between women with 2 versus ≥ 3 pregnancy losses with the exception of age ≥ 35 years and MTHFR A1298C heterozygote mutation. No difference was found between women with primary and secondary RPL stratified according to the number of abnormalities detected (Chi-square: 8.55, P = 0.07). In these women, the only factors found to be present with statistically different rates were age ≥ 35 years, cigarette smoking, and genital infection by Ureaplasma. CONCLUSION: A patient-based diagnostic approach in women with RPL could be clinically useful and could represent a basis for future research.

Endometrial Microbiota and Immune Tolerance in Pregnancy.

Recent studies have demonstrated that the uterus has its own microbiota. However, there is no consensus on endometrial microbiota composition, thus its role in the healthy uterine environment is still a frontier topic. Endometrial receptivity is key to embryo implantation, and in this specific context immunological tolerance against fetal antigens and the tightly regulated expression of inflammatory mediators are fundamental. According to recent evidence, endometrial microbiota may interact in a very dynamic way with the immune system during the peri-conceptional stage and later during pregnancy. For this reason, a condition of dysbiosis might lead to adverse pregnancy outcomes. The aim of this review is to summarize the evidence on the molecular mechanisms by which the endometrial microbiota may interact with the immune system. For this purpose, the link between dysbiosis and reproductive disorders, such as infertility, recurrent pregnancy loss (RPL), and preterm birth, will be discussed. In conclusion, the most recent findings from molecular analyses will be reported to illustrate and possibly overcome the intrinsic limitations of uterine microbiota detection (low endometrial biomass, high risk of contamination during sampling, and lack of standardization).

HLA-G and Recurrent Pregnancy Loss.

Placentation is an immunological compromise where maternal immune system cells and trophoblastic cells interact to reach an equilibrium condition. Although the cross talk between the two systems is complex and not completely understood, Human Leukocyte Antigen G (HLA-G), expressed on trophoblastic cell surfaces, seems to be one of the main molecules involved in the modulation of both local and systemic maternal immune response. The prevalence of recurrent pregnancy loss (RPL), probably underestimated, is 5% of all women who achieve pregnancy, and about 40-60% percent of RPL cases are unexplained. There is an immunological analogy between allograft rejection and miscarriage, and the purpose of this review is to describe how the HLA-G pathway alterations are involved in disrupting the immunologic balance and in increasing the risk of recurrent pregnancy loss.

Antiphospholipid Syndrome in Pregnancy: New and Old Pathogenetic Mechanisms.

The antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized, according to the Sydney criteria, by the persistent presence of autoantibodies directed against phospholipid-binding proteins associated with thrombosis and/or obstetrical complications. The most frequent complications in obstetric antiphospholipid syndrome are recurrent pregnancy losses and premature birth due to placental insufficiency or severe preeclampsia. In recent years, vascular APS (VAPS) and obstetric APS (OAPS) have been described as two different clinical entities. In VAPS, antiphospholipid antibodies (aPL) interfere with the mechanisms of coagulation cascade and the 'two hit hypothesis' has been suggested to explain why aPL positivity does not always lead to thrombosis. OAPS seems to involve additional mechanisms, such as the direct action of anti-ß2 glycoprotein-I on trophoblast cells that can lead to a direct placental functional damage. Furthermore, new actors seem to play a role in the pathogenesis of OAPS, including extracellular vesicles, micro-RNAs and the release of neutrophil extracellular traps. The aim of this review is to investigate the state-of-the-art antiphospholipid syndrome pathogenesis in pregnancy, in order to provide a comprehensive overview of both old and new pathogenetic mechanisms involved in this complex disease.

Syncytiotrophoblast-derived extracellular vesicles carry apolipoprotein-E and affect lipid synthesis of liver cells in vitro.

In normal pregnancy, hepatic metabolism adaptation occurs with an increase in lipid biosynthesis. Placental shedding of syncytiotrophoblast-derived extracellular vesicles (STBEVs) into the maternal circulation constitutes a major signalling mechanism between foetus and mother. We investigated whether STBEVs from normal pregnant women might target liver cells in vitro and induce changes in lipid synthesis. This study was performed at the Nuffield Department of Women's & Reproductive Health, Oxford, UK. STBEVs were obtained by dual-lobe placental perfusion from 11 normal pregnancies at term. Medium/large and small STBEVs were collected by ultracentrifugation at 10,000g and 150,000g, respectively. STBEVs were analysed by Western blot analysis and flow cytometry for co-expression of apolipoprotein-E (apoE) and placental alkaline phosphatase (PLAP). The uptake of STBEVs by liver cells and the effect on lipid metabolism was evaluated using a hepatocarcinoma cell line (HepG2 cells). Data were analysed by one-way ANOVA and Student's t test. We demonstrated that: (a) STBEVs carry apoE; (b) HepG2 cells take up STBEVs through an apoE-LDL receptor interaction; (c) STBEV incorporation into HepG2 cells resulted in (i) increased cholesterol release (ELISA); (ii) increased expression of the genes SQLE and FDPS (microarray) involved in cholesterol biosynthesis; (iii) downregulation of the CLOCK gene (microarray and PCR), involved in the circadian negative control of lipid synthesis in liver cells. In conclusion, the placenta may orchestrate the metabolic adaptation of the maternal liver through release of apoE-positive STBEVs, by increasing lipid synthesis in a circadian-independent fashion, meeting the nutritional needs of the growing foetus.

Modulation of matrix metalloproteases by ciliary neurotrophic factor in human placental development.

Ciliary neurotrophic factor (CNTF) is a pleiotropic cytokine that signals through a receptor complex containing a specific subunit, CNTF receptor α (CNTFRα). The two molecules are constitutively expressed in key structures for human placental growth and differentiation. The possible role of CNTF in enhancing cell proliferation and/or invasion during placental development and remodelling was investigated using HTR-8/SVneo and BeWo cells, taken respectively as cytotrophoblast and syncytiotrophoblast models. In both cell lines, treatment with human recombinant (hr) CNTF activated JAK2/STAT3 signalling and inhibited the ERK pathway. Interestingly, in HTR-8/SVneo cells, 50 ng hrCNTF induced significant downregulation of matrix metalloprotease (MMP)-1 and significant upregulation of MMP-9. Moreover, pharmacological inhibition of JAK2/STAT3 signalling by AG490 and curcumin resulted in MMP-9 downregulation; it activated the ERK signalling pathway and upregulated MMP-1 expression. Collectively, these data suggest a role for CNTF signalling in extravillous cytotrophoblast invasion through the modulation of specific MMPs.

CD93 a potential player in cytotrophoblast and endothelial cell migration.

CD93, also known as complement component C1q receptor, is expressed on the surface of different cellular types such as monocytes, neutrophils, platelets, microglia, and endothelial cells, and it plays a pivotal role in cell proliferation, cell migration, and formation of capillary-like structures. These processes are strictly regulated, and many fetal and maternal players are involved during placental development. At present, there are no studies in literature regarding CD93 in placental development, so we investigated CD93 expression in first and third trimester and PE placentas by immunohistochemistry and western blotting analysis. In addition, we performed in vitro experiments under oxidative stress conditions to demonstrate how oxidative stress acts on CD93 protein expression. Our data showed that CD93 was expressed in villous cytotrophoblast cells, in some fetal vessels of first and third trimester and PE placentas and in the extravillous cytotrophoblast of cell columns in the first trimester placentas. Moreover, we detected a significant decrease of CD93 expression in third trimester and PE placentas compared to first trimester placentas, while no differences were detected between third and PE placentas. No differences of CD93 expression were detected in oxidative stress conditions. We suggest that CD93 can guide extravillous cytotrophoblast migration through ß1-integrin in uterine spiral arteries during placentation in the first trimester of pregnancy and that the decrease of CD93 expression in third trimester and PE placentas could be linked to the poor extravillous cytotrophoblast cells migration. So, it might be interesting to understand the role of CD93 in the first phases of PE onset.

Alpha-Lipoic Acid Plays a Role in Endometriosis: New Evidence on Inflammasome-Mediated Interleukin Production, Cellular Adhesion and Invasion.

Endometriosis is an estrogen-linked gynecological disease defined by the presence of endometrial tissue on extrauterine sites where it forms invasive lesions. Alterations in estrogen-mediated cellular signaling seems to have an essential role in the pathogenesis of endometriosis. Higher estrogen receptor (ER)-ß levels and enhanced ER-ß activity were detected in endometriotic tissues. It is well known that ER-ß interacts with components of the cytoplasmic inflammasome-3 (NALP-3), the NALP-3 activation increases interleukin (IL)-1ß and IL-18, enhancing cellular adhesion and proliferation. Otherwise, the inhibition of ER-ß activity suppresses the ectopic lesions growth. The present study aims to investigate the potential effect of α-lipoic acid (ALA) on NALP-3 and ER-ß expression using a western blot analysis, NALP-3-induced cytokines production by ELISA, migration and invasion of immortalized epithelial (12Z) and stromal endometriotic cells (22B) using a 3D culture invasion assay, and matrix-metalloprotease (MMPs) activity using gelatin zymography. ALA significantly reduces ER-ß, NALP-3 protein expression/activity and the secretion of IL-1ß and IL-18 in both 12Z and 22B cells. ALA treatment reduces cellular adhesion and invasion via a lower expression of adhesion molecules and MMPs activities. These results provide convincing evidence that ALA might inhibit endometriosis progression.

Abnormal uterine inflammation in obstetric syndromes: molecular insights into the role of chemokine decoy receptor D6 and inflammasome NLRP3.

The adaptation of the uterine environment into a favorable immunological and inflammatory milieu is a physiological process needed in normal pregnancy. A uterine hyperinflammatory state, whether idiopathic or secondary to hormonal or organic uterine disorders (polycystic ovary syndromes, endometriosis/adenomyosis and fibroids), negatively influences the interactions between decidua and trophoblast, early in gestation, and between chorion and decidua later in pregnancy. Abnormal activation of uterine inflammatory pathways not only contributes to the pathogenesis of the obstetric syndromes, i.e. recurrent pregnancy loss (RPL), pre-term delivery (PTD) and pre-eclampsia (PE), but also to correlates with severity. In this review, we summarize recent advances in the knowledge of uterine molecular mechanisms of inflammatory modulation in normal pregnancy and obstetric syndromes (RPL, PTD and PE). In particular, we focus on two regulators of uterine/placental inflammation: the NLRP3 inflammasome and the chemokines decoy receptor D6. We performed comprehensive review of the literature in PubMed and Google Scholar databases from 1994 to 2018. The available evidence suggests that: (i) the expression of inflammasome NLRP3 is increased in the endometrium of women with unexplained RPL, in the chorioamniotic membranes of women with PTL and in the placenta of women with PE; (ii) there is a role for abnormal expression and function of D6 decoy receptor at the feto-maternal interface in cases of RPL and PTD and (iii) the function of placental D6 decoy receptor is impaired in PE. A wider comprehension of the inflammatory molecular mechanisms involved in the pathogenesis of the obstetric syndromes might lead to the identification of new potential therapeutic targets.

Role of Human Leukocyte Antigens at the Feto-Maternal Interface in Normal and Pathological Pregnancy: An Update.

The successful maternal tolerance of the semi-allogeneic fetus provides an apparent immunologic paradox. Indeed, deep invasion of placental trophoblast cells into maternal uterine tissue and the following growth of the fetus have to be tolerated by a pregnant woman's immune system. Among the various possible protective mechanisms that may be involved in human pregnancy, the expression of a non-classical pattern of human leukocyte antigen (HLA) class I molecules and the complete lack of expression of HLA class II molecules in placental tissues seem to be the most relevant mechanisms of fetal escape from maternal immune recognition. The importance of HLA molecules in fetal toleration by the maternal immune system is highlighted by pregnancy complications occurring in cases of abnormal HLA molecule expression at the maternal-fetal interface. In this review, we summarize evidences about the role of placental HLA molecules in normal and pathological pregnancies.

Pre-eclampsia onset and SPARC: A possible involvement in placenta development.

Pre-eclampsia (PE) is a multisystem disorder commonly diagnosed in the latter half of pregnancy and it is a leading cause of intrauterine fetal growth retardation (IUGR). The aim of this study was to investigate the localization and the role of SPARC, secreted protein acidic, and rich in cysteine, in PE and PE-IUGR placentas in comparison with normal placentas. SPARC was mainly expressed in the villous and extravillous cytotrophoblastic cells in first trimester, whereas in PE, PE-IUGR and at term placentas, SPARC immunostaining was visible in both cytotrophoblastic cells and syncytiotrophoblast. SPARC expression significantly decreased in normal placenta from first to third trimester and a further significant reduction was demonstrated in PE and PE-IUGR. The latter downregulation of SPARC depends on hypoxic condition as shown by in vitro models. In conclusion, SPARC can play a pivotal role in PE and PE-IUGR onset and it should be considered as a key molecule for future investigations in such pathologies.

Endometrial Immune Dysfunction in Recurrent Pregnancy Loss.

Recurrent pregnancy loss (RPL) represents an unresolved problem for contemporary gynecology and obstetrics. In fact, it is not only a relevant complication of pregnancy, but is also a significant reproductive disorder affecting around 5% of couples desiring a child. The current knowledge on RPL is largely incomplete, since nearly 50% of RPL cases are still classified as unexplained. Emerging evidence indicates that the endometrium is a key tissue involved in the correct immunologic dialogue between the mother and the conceptus, which is a condition essential for the proper establishment and maintenance of a successful pregnancy. The immunologic events occurring at the maternal-fetal interface within the endometrium in early pregnancy are extremely complex and involve a large array of immune cells and molecules with immunoregulatory properties. A growing body of experimental studies suggests that endometrial immune dysregulation could be responsible for several, if not many, cases of RPL of unknown origin. The present article reviews the major immunologic pathways, cells, and molecular determinants involved in the endometrial dysfunction observed with specific application to RPL.

Helicobacter pylori infection contributes to placental impairment in preeclampsia: basic and clinical evidences.

BACKGROUND: Preeclampsia (PE) is a major cause of maternal and neonatal morbidity and mortality. Epidemiological association between Helicobacter pylori (Hp) infection and PE onset has been widely shown. The aim of this study was to analyze a possible correlation between Hp infection and the severity of clinical presentation of PE and to identify an immunologic mechanism triggered by Hp infection potentially contributing to the pathogenesis of PE. MATERIALS AND METHODS: Sera from 93 preeclamptic women and 87 healthy pregnant women were tested for Hp infection by immunoassay and for anti-CagA antibodies by Western blot assay. The serologic results were correlated with the clinical features of PE. The functional effect of serum IgG fractions, positive or negative for Hp, from preeclamptic women or controls were tested on trophoblast and endothelial cell cultures and in a murine model of angiogenesis. RESULTS: Preeclamptic women showed higher seroprevalence of Hp infection (57.0%) compared to controls (33.3%) (P<.001). The seropositivity for CagA-positive strains of Hp was 45.2% in preeclamptic women vs 13.7% in controls (P<.001). In PE women, Hp infection was associated with abnormality of uterine arteries Doppler (P<.001). Hp+ IgG fractions from preeclamptic women bound to trophoblast and endometrial endothelial cell cultures, reducing in vitro invasiveness and angiogenesis, respectively, and inhibited angiogenesis in mice. CONCLUSIONS: Our data show, for the first time, an association between Hp infection and PE with abnormal uterine arteries Doppler velocimetry, suggesting a role for Hp infection in impairing placental development and increasing the risk to develop PE. This study opens the new perspective of a potential screening and treatment for Hp infection in pregnancy.