Embryo implantation

Endometriosis is frequently related to infertility and little is known about the mechanisms underlying this association. Some studies point to an endometrial factor involved in this condition, which could compromise embryo implantation. Progesterone plays crucial role in endometrial receptivity by acting through progesterone receptor ( PGR) isoforms PR-A and PR-B whose expression is epigenetically regulated by DNA methylation, in a specific promoter region for each isoform. Epigenetic changes in PGR-A and PGR-B may be related to progesterone resistance of endometriosis-related infertility...

There are few treatments for patients with recurrent pregnancy loss (RPL) or recurrent implantation failure (RIF). Women with RPL and unexplained infertility have lower T regulatory cell (Treg ) expression when compared to fertile controls. A murine model has been developed with depletion of regulatory T cells (DEREG) after administration of diphtheria toxin (DT), resulting in smaller litter sizes, secondary to embryo implantation failure. Numerous murine studies have shown that adoptive transfer of CD4+ CD25+ FoxP3+ Tregs from donors improves litter sizes in DEREG mice with depleted Tregs ...

In a previous study we found the expression of epithelial-mesenchymal transition (EMT) biomarkers, including E-cadherin and N-cadherin, was significantly altered in uterine endometrium during embryo implantation via regulation by microRNA (miRNA)-429 and protocadherin-8 (Pcdh8). As a natural continuation of the previous study, the aim of the present study was to explore the role of EMT during embryo implantation and the potential activity of twist basic helix-loop-helix transcription factor 2 (Twist2) in regulating embryo implantation...

AIM: To analyze the effects of high ovarian response on endometrial collagen synthesis and related gene expression during the peri-implantation period in patients undergoing in vitro fertilization-embryo transfer. METHODS: Peripheral blood and endometrial biopsies were obtained from infertile women on day 6 after oocytes retrieval or ovulation in 16 stimulated cycles (SC) and 16 natural cycles (NC) respectively. Serum estrogen (E2 ), progesterone (P4 ), histological staging, endometrial collagen, matrix metalloproteinases (MMP2, 9) and tissue inhibitors of metalloproteinases (TIMP1, 3) were assayed...

Mesenchymal stem cells (MSCs), which are pluripotent cells with immunomodulatory properties, have been considered good candidates for the therapy of several immune disorders, such as inflammatory bowel diseases, concanavalin A-induced liver injury, and graft-versus-host disease. The embryo is a natural allograft to the maternal immune system. A successful pregnancy depends on the timely extinction of the inflammatory response induced by embryo implantation, followed by the switch to a tolerant immune microenvironment in both the uterus and the system...

Elevation of progesterone during the late follicular phase of stimulated in-vitro fertilization cycles is a frequent event, which negatively impacts the outcome. Over the years evidence has demonstrated a direct relationship between late-follicular elevated progesterone and endometrial receptivity. In this regard, elective cryopreservation of all good quality embryos and transfer in a subsequent frozen/thawed cycle is the most common strategy adopted by clinicians in case of elevated progesterone. Nonetheless, recent evidence suggests that elective cryopreservation might not entirely resolve the reduced pregnancy outcomes associated with the elevation of progesterone, considering that the increase may affect not only implantation, but also embryo quality...

RESEARCH QUESTION: What pregnancy rates are achieved after transfer of cryopreserved double slow-frozen embryos in IVF cycles? Patients in whom surplus thawed cleaved embryos (day 2 or 3) were grown to the blastocyst stage, re-frozen and then re-thawed for transfer (double freezing) were included. DESIGN: Data were collected on all patients who had undergone the above procedure at the IVF unit of Assuta Ramat Hachayal Hospital, Tel Aviv, during a 7-year period. For each patient in the study group, the two-consecutive, matched-by-age patients treated with frozen-thawed single blastocyst transfer were selected to form a 2:1 ratio control group...

Background: Endometriosis, can cause ovarian conflict and reduced ovarian reserve that could lead to lower response to assisted reproductive techniques. Objective: Current study was conducted to determine the association between level of anti-mullerian hormone (AMH) and the infertility treatment outcomes in infertile females with endometriosis versus the non-endometriosis infertile subject. Materials and Methods: In this case-control study, 64 infertile females who referred to Shariati Hospital from April 2015 to November 2017 were enrolled...

Impaired decidualization has been considered a major cause of infertility in adenomyosis. However, the mechanism remains poorly understood. Recent studies suggest that micro RNAs (miR) play a crucial role in embryo implantation. The aim of the present study was to identify the role of miR-21 in human endometrial stromal cell (hESC) decidualization in vitro. To explore the roles of miR-21 in decidualization, we detected the expression of miR-21 in the endometrium of fertile control and adenomyosis patients, and analyzed the effects of miR-21 on the biological behaviors of hESC decidualization...

TGF-β signaling in the endometrium is active during the implantation period and has a pivotal role in regulating endometrial receptivity and embryo implantation. During embryo implantation, both apoptosis and proliferation of endometrial cells happen at the same time and it seems TGF-β is the factor that controls both of these processes. As shown in cancer cells, in special conditions this cytokine can have a dual effect and switch the action from apoptosis to proliferation. Owing to the similarity between embryo implantation and cancer development and also unusual pattern of proliferation and remodeling in the uterus, in this review we suggest the existence of such a switching in endometrium during the early pregnancy...

RESEARCH QUESTION: Do serum vitamin D levels in men and women undergoing IVF/intracytoplasmic sperm injection (ICSI) affect embryo development and clinical outcomes? DESIGN: A large retrospective observational cohort study conducted between March 2016 and March 2017; plasma 25-OHD levels were measured before ovarian stimulation in couples undergoing IVF/ICSI (including 1883 women and 1720 men). RESULTS: Women were divided into four groups in terms of serum 25-OHD quartiles: <14...

Autoimmune Regulator (AIRE) regulates central immune tolerance by inducing expression of tissue-restricted antigens in thymic medullary epithelial cells, thereby ensuring elimination of autoreactive T cells. Aire mutations in humans and targeted Aire deletion in mice results in multi-organ autoimmune disease, known in humans as Autoimmune Polyglandular Syndrome Type 1 (APS-1). APS-1 is characterized by presence of adrenal insufficiency, chronic mucosal candidiasis, and/or hypoparathyroidism. Additionally, females often present with gonadal insufficiency and infertility...

OBJECTIVE: To study if hysteroscopy (HSC) before starting an in-vitro fertilization (IVF) cycle improves IVF outcomes in women with recurrent implantation failure (RIF). METHODS: The Medline, Cochrane, EMBASE, and Google Scholar databases were searched using the following keywords until March 31, 2017: in-vitro fertilization; infertility; hysteroscopy; recurrence; embryo implantation; and pregnancy. Randomized controlled trials (RCTs), two-arm prospective studies, and retrospective studies were included...

Hypothyroidism has been linked to infertility, but the mechanisms underlying infertility-related hypothyroidism have yet to be fully elucidated. Therefore, in this study, effects of hypothyroidism on expression of the proteins related to thyroid hormone function in the uterus, which were thought to play a role implantation, including thyroid hormone receptor (TR), thyroid stimulating hormone receptor (TSHR), retinoic acid receptor (RAR) and extracellular kinase (ERK) were identified. Pregnant female rats were rendered hypothyroid by giving methimazole (MMI), orally...

Pre-implantation embryo development encompasses several key developmental events, especially the activation of zygotic genome activation (ZGA)-related genes. Endogenous retroviruses (ERVs), which are regarded as "deleterious genomic parasites", were previously considered to be "junk DNA". However, it is now known that ERVs, with limited conservatism across species, mediate conserved developmental processes (e.g., ZGA). Transcriptional activation of ERVs occurs during the transition from maternal control to zygotic genome control, signifying ZGA...

PURPOSE: Preimplantation genetic testing (PGT) using Karyomapping is used to screen embryos for single gene disorders prior to implantation. While Karyomapping is not designed to screen for abnormalities in chromosome copy number, this testing is based upon a genome-wide analysis of single nucleotide polymorphisms (SNP) and, as such, some chromosome abnormalities are detected. The aim of this study was to validate whether Karyomapping could provide reliable and accurate PGT for a paternal 46,XY,t(10;19)(p15;p13...

INTRODUCTION: Medically assisted reproduction in natural cycle has been investigated, especially in women with poor response to conventional ovarian stimulation, with endometrial receptivity improvement, lower cost and possibility of successive cycles. The disadvantages are: lower profitability per treatment cycle and higher cancellation rate. The aim of this study was to determine the rate of clinical pregnancy in infertile women subjected to medically assisted reproduction in natural cycle...

Objective: To study the potential role of miR-30a-3p in embryo implantation and explore underlying mechanisms. Methods: We first established normal pregnancy, pseudopregnancy, delayed implantation, and artificial decidualization mouse models. Next, we detected miR-30a-3p expression profiles of these models with real-time reverse transcription PCR(qRT-PCR), then predicted potential target genes through a dual-luciferase assay. Immunofluorescence-fluorescence in situ hybridization co-located miR-30a-3p and target genes...

Repeat breeder cattle do not become pregnant until after three or more breeding attempts; this represents a critical reproductive disorder. Embryo transfer (ET) following artificial insemination (AI) in repeat breeder cattle reportedly improves pregnancy rate, leading to speculation that interferon tau (IFNT) is associated with this phenomenon. However, the reason why the conception rate improves remains unknown. We investigated the effect of ET following AI on repeat breeder cattle in field tests, and determined whether adding an embryo affects the maternal immune cells detected by interferon-stimulated genes (ISGs), marker genes of IFN response...

OBJECTIVE(S): The aim of this study was to compare the patient characteristics, type of genetic disease and inheritance, volume of activity, practice patterns and pregnancy outcomes, in private versus publically funded IVF pre-implantation genetic testing (PGT) for translocation (IVF-PGT-SR) and aneuploidy (PGT-A) periods. STUDY DESIGN: This study retrospectively analyzed data during both privately funded period (PRP) and publically funded period (PUP) of assisted reproductive technology (ART) for a total of 275 patients...