Search Results (88)

The role of the endometrial microbiome in embryo implantation remains incompletely understood. While most studies have focused on taxonomic composition and Lactobacillus dominance, the ecological organization of microbial communities associated with implantation success has received limited attention. The aim of this study was to investigate whether implantation outcome following euploid embryo transfer is associated with differences in endometrial microbial network structure and community organization. Endometrial biopsies collected during the window of implantation from 95 women undergoing subsequent euploid embryo transfer were analyzed using 16S rRNA gene sequencing. Microbial diversity, co-occurrence networks, community structure, hub taxa, network robustness, and microbial association patterns were evaluated. The Pregnant group demonstrated a more interconnected microbial network with a greater number of significant associations, larger ecological modules, and increased network integration than the Non-pregnant group. Seventeen microbial associations were unique to the Pregnant network, whereas eleven were unique to the Non-pregnant network, indicating implantation-associated ecological rewiring. Lactobacillus-centered association patterns also differed between groups. These findings suggest that successful implantation is associated with coordinated endometrial microbial community organization rather than changes in individual taxa. Microbial network structure may represent a novel dimension of endometrial receptivity assessment. Full article

Reliable preimplantation embryo sexing is relevant in cattle breeding; however, PCR-based Y-marker detection may be sensitive to limited DNA input and sample-type-specific properties of embryo-derived material. In this observational study, we examined assay-output patterns in a low-input multiplex PCR workflow targeting a male-specific Y-chromosome marker (MSY) together with an autosomal internal control targeting cyclin-dependent kinase 1 (CDK1). A total of 141 bovine embryo-derived samples were analyzed across three sample categories: whole embryos, cleavage-stage blastomere biopsies, and blastocyst-stage trophectoderm biopsies. Assay evaluability differed across sample categories, being highest in blastocyst-stage biopsy samples (90.6%, 29/32), intermediate in whole embryos (82.9%, 58/70), and lowest in blastomere-biopsy samples (64.1%, 25/39). Among technically evaluable CDK1-positive samples, apparent MSY-positive classification also differed across categories, with rates of 55.2% (32/58) in whole embryos, 52.0% (13/25) in blastomere-biopsy samples, and 6.9% (2/29) in blastocyst-stage biopsy samples. In a same-lysate repeat-amplification subset, overall evaluability concordance was 92.5% and overall apparent MSY-based classification concordance was 88.2%, although subgroup sizes were limited. Because no independent reference method for true embryo sex was available and sample category was structurally confounded with developmental stage, semen type, sire, and partly PCR-date structure, the findings should be interpreted as assay-output observations rather than measures of biological sex ratio or diagnostic sexing accuracy. Overall, embryo-derived sample categories showed differing assay evaluability and apparent MSY-classification patterns within this low-input PCR setting, supporting the need for sample-type-specific validation when low-cell embryo-derived samples are used. Full article

Background/Objectives: Endometrial B-cell lymphoma 6 (BCL6) overexpression has been proposed as a marker of progesterone resistance, occult endometriosis, and endometrial dysfunction in infertile women. Its possible association with reproductive outcomes and its potential role in guiding management before embryo transfer have attracted increasing interest. However, the prognostic and clinical significance of BCL6 across infertility settings remains incompletely defined. We systematically reviewed the literature on endometrial BCL6 expression and reproductive outcomes in infertile women. Methods: This systematic review was conducted according to a prospectively registered PROSPERO protocol. Studies evaluating endometrial BCL6 expression on biopsy in infertile women were eligible if they reported reproductive outcomes or clinically relevant comparative data. Two prespecified questions were addressed: whether high or abnormal BCL6 expression is associated with poorer reproductive outcomes than low or normal expression, and whether treatment before embryo transfer improves outcomes in BCL6-positive women. Thirteen studies were included in the review. Because the included studies differed substantially in infertility phenotype, embryo context, hormonal preparation, biopsy timing, and outcome reporting, findings were synthesized narratively. Results: The available evidence suggests that abnormal or elevated endometrial BCL6 expression may be associated with poorer reproductive outcomes in some infertility populations, particularly in women with unexplained infertility undergoing IVF, although this pattern was less evident in selected euploid embryo transfer cohorts. Treatment-oriented studies suggested a possible benefit of pre-transfer medical suppression or surgical management in some BCL6-positive women, but findings were variable across studies. Supportive non-comparative and mechanistic studies further indicated that interpretation of BCL6 is influenced by hormonal preparation, endometrial context, and whether BCL6 is considered in isolation or within a broader biological or multimarker framework. Interpretation of the available evidence was constrained by the limited number of comparative studies, observational study designs, variability in clinical populations, and incomplete standardization of reproductive outcome reporting. Conclusions: Endometrial BCL6 appears biologically and clinically relevant as a marker of endometrial dysfunction in selected infertility settings, but current evidence is insufficient to support routine stand-alone clinical use or strong treatment recommendations. Its apparent prognostic and clinical utility varies across patient populations and reproductive settings. Larger prospective comparative studies with harmonized biopsy protocols, standardized outcome reporting, and independent external validation are needed to clarify the role of BCL6 in reproductive medicine. Full article

Background/Objectives: Aging is increasingly recognized as a key determinant of changes in human tissue and cellular function. Women’s age, in particular, has been associated with reduced oocyte quality and negatively correlated with the expression of genes involved in endometrial decidualization and cellular function. The ability of endometrial cells to interact and allow the invasion of the growing embryo is defined as endometrial receptivity. Investigating age-related differences in human endometrial receptivity may expand our understanding of factors contributing to infertility. Methods: Stromal cells were isolated and cultured from endometrial pipelle biopsies (n = 28) obtained from female donors at the proliferative phase of the menstrual cycle. Protein and mRNA expression of the receptivity modulators OPN, CD44, and HOXA10 were analyzed by Western blot and real-time PCR, respectively. Results: Data presented a linear decrease in mRNA expression of OPN and HOXA10 (p = 0.0066, R² = 0.3018 and p = 0.0036, R² = 0.529, respectively) with women’s increasing age, and a similar trend was evident at the protein level (OPN, p < 0.05; HOXA10, p < 0.01). Further analysis of the data included separating the samples into three age groups: 25–35 years, 36–40 years, and 41–46 years. ANOVA revealed a significant decrease in OPN and HOXA10 mRNA expression (p = 0.03158 and p = 0.02578, respectively). CD44 expression did not differ with age. Conclusions: OPN and HOXA10 are negatively correlated with increasing maternal age. These findings suggest that age-related alterations in key endometrial receptivity modulators may contribute to impaired implantation and could represent potential targets for diagnostic or therapeutic strategies in human implantation failure. Full article

Preimplantation embryo genomic selection (eGS) enables selection prior to implantation and could accelerate genetic gain in cattle. A major hurdle is the limited DNA from embryo biopsies, requiring efficient whole-genome amplification (WGA) for accurate genomic analyses. However, alternative WGA methods and genotyping strategies have not been systematically compared in cattle. This study evaluated different methods for WGA (multiple displacement amplification (MDA) or multiple annealing and looping-based amplification cycles (MALBAC)) and for genotyping (single nucleotide polymorphism array (SNP-array), genotyping by targeted sequencing (GBTS), or whole-genome sequencing (WGS)) using 3-, 6-, and 9-cell bovine samples. MDA consistently outperformed MALBAC across various performance metrics, including amplification length, call rates, genome coverage (93.43–94.40% vs. 53.01–67.08%), and genotyping concordance (0.89–0.98 vs. 0.75–0.92). GBTS achieved the highest call rates, while SNP-array and GBTS showed excellent concordance and low error rates. WGS provided genome-wide data for precise aneuploidy detection. We further validated the workflow in trophectoderm biopsies and arrested embryos, generating reliable data for genomic evaluation, sex determination, and aneuploidy screening. MDA from ≥6 cells combined with GBTS or SNP-array showed a favorable balance of efficiency and accuracy for bovine eGS. This framework may facilitate the application of eGS in cattle breeding by enhancing selection intensity and accelerating genetic improvement. Full article

Background/Objectives: In the last decade, non-invasive methods for aneuploidy detection have been explored. The most successful approach involves analyzing the cell-free DNA (cfDNA) released by the embryo into the culture medium. The main objective of this study is to examine the technical feasibility of this new approach called non-invasive PGT-A or niPGT-A. In addition, as an exploratory objective, the impact of the niPGT-A results on clinic outcomes will be assessed. Methods: This was a multicenter, international study that included 716 patients and 2539 blastocysts (ClinicalTrials.gov: NCT03520933). Each embryo was cultured following a specific protocol for niPGT-A. Individual spent blastocyst medium (SBM) and trophectoderm (TE) biopsy were obtained, analyzed, and compared to assess concordance. In a subset of embryos, the comparison also included an inner cell mass (ICM) biopsy. Clinical outcomes from the embryo transfers performed (all based on the TE result) were registered, and results were analyzed blindly regarding the impact of aneuploidies in the culture medium. Results: The concordance rate between SBM and TE was 79.1% (range: 74.1–82.1; cycles with autologous oocytes). This value increased to 87.0% when comparing SBM and ICM. Applying an adapted embryo culture protocol to collect the SBM for niPGT-A did not affect blastocyst quality. Analysis of the embryo transfers performed (n = 265) revealed a trend towards lower miscarriage rate in blastocysts where both TE and SBM were concordant and euploid (13.0%), compared to blastocysts with a euploid TE and an aneuploid SBM (22.2%). Conclusions: The results obtained show a high concordance between the SBM and TE biopsies. Although additional refinement of the technique would further increase niPGT-A’s performance, the results obtained support the potential use of this non-invasive approach for aneuploidy detection. The high concordance of the cfDNA present in the SBM with the corresponding ICM biopsy and the miscarriage rate observed in cases with an aneuploid SBM, despite the euploid TE results, also support niPGT-A’s capacity to assess embryo aneuploidies and its potential as a prioritization system for selecting blastocysts to transfer. This approach could hold special interest in patients with no PGT-A indications, couples that prefer not to biopsy their embryos or those who do not have access to invasive PGT-A. Full article

Background/Objectives: Laser-assisted zona pellucida (ZP) drilling on day 4 embryos is routinely performed in IVF laboratories to facilitate trophectoderm (TE) herniation for blastocyst biopsy. Nevertheless, inner cell mass (ICM) herniation through the initial ZP opening occasionally occurs and may interfere with standard TE biopsy. Methods: This retrospective study assessed the clinical and obstetric safety of a double ZP drilling strategy for TE biopsy in preimplantation genetic testing for aneuploidy (PGT-A) cycles. A total of 560 single euploid embryo transfer cycles were analyzed. Blastocysts were categorized (Groups 1–6) based on ICM/TE herniation patterns and the corresponding biopsy approach. Clinical outcomes were compared between cycles undergoing TE biopsy through a single ZP opening (TE hatching with ICM remaining within the ZP) and cycles requiring a second opening to relocate the biopsy site when the ICM herniated through the original opening or was positioned externally. Results: The single-opening approach of Group 1 accounted for 295 cycles (52.7%), with implantation, miscarriage, and live birth rates of 65.4%, 14.0%, and 56.3%, respectively. The double-opening approach of Group 3 was applied in 21 cycles (3.8%), yielding implantation, miscarriage, and live birth rates of 66.7%, 0%, and 66.7%, respectively. No significant differences were observed between the two strategies in implantation, miscarriage, or live birth rates. Obstetric and neonatal outcomes, including gestational age, birth weight, and monozygotic twinning incidence, were comparable. Fifteen healthy infants were delivered following TE biopsy using the double-opening strategy. Conclusions: These data support incorporating ICM position into TE biopsy decision-making and suggest that creating a second ZP opening to reposition the biopsy site is clinically feasible and does not compromise reproductive or obstetric outcomes in PGT-A cycles. Full article

Background and Objectives: Aneuploidy is the leading cause of implantation failure and miscarriage, with prevalence increasing with maternal age. Embryos classified as chaotic, characterized by the presence of five or more chromosomal abnormalities, and those with complex aneuploidies, defined by two to four abnormalities, represent a controversial category in preimplantation genetic testing for aneuploidy (PGT-A), as the potential for misclassification remains a significant concern. Materials and Methods: We performed a retrospective study at the Calla IVF Center, Oradea, analyzing 230 blastocysts grouped by maternal age (25–30, 31–35, 36–40, and 41–50 years). A trophoblast biopsy was performed on days 5–7, and the samples were analyzed by next-generation sequencing (NGS). Embryos were classified as euploid, aneuploid, mosaic, or chaotic. The 19 embryos initially diagnosed as chaotic were thawed and subjected to re-biopsy. Statistical analysis included descriptive statistics (chi-square tests and ANOVA) and multivariable regression models, with p < 0.05 as the criterion for statistical significance. Results: Aneuploidy increased with maternal age, from 29.6% in women aged 25–30 years to 68.7% in those aged 41–50 (p = 0.002). Poor-quality blastocysts exhibited higher aneuploidy rates (72.4%) than good-quality embryos (34.6%; p = 0.004). Chaotic embryos comprised 8.3% of the cohort. Upon re-biopsy, none were confirmed as euploid; all remained abnormal and were reassigned to aneuploid, mosaic, or persistently chaotic categories. This finding suggests that apparent euploid results reported elsewhere may reflect technical variability and sampling limitations in PGT-A rather than accurate chromosomal normalization. Conclusions: The prevalence of aneuploid embryos showed a progressive increase with advancing maternal age. Chaotic embryos are heterogeneous, and re-biopsy may help refine the interpretation of complex PGT-A profiles, supporting its role as a diagnostic and quality control tool rather than a strategy to identify euploid embryos. Our study offers novel insights through age-stratified analysis, the integration of morphology with genetics in a Romanian IVF cohort, and a detailed evaluation of chaotic embryos, providing clinical recommendations for patient counseling and embryo selection. Full article

A predominant etiological factor in implantation failure and early pregnancy loss is embryonic chromosomal abnormalities. The current clinical standard for determining embryonic ploidy is invasive preimplantation genetic testing. This procedure imposes mechanical stress on embryonic cells during trophectoderm biopsy and fails to significantly improve live birth rates per transfer, likely due to its inability to evaluate the embryo’s implantation potential. Consequently, there is a clear need to develop a non-invasive method, suitable for routine clinical practice, that can simultaneously assess both the ploidy and implantation competence of a blastocyst prior to uterine transfer. Our research group was the first to achieve this by quantifying specific piwiRNAs (piR_016677, piR_017716, piR_020497, piR_015462) in spent culture medium. These data served as the foundation for logistic regression models tailored for day 5 blastocysts, day 6 blastocysts, and blastocysts irrespective of their developmental rate. These models demonstrated high diagnostic accuracy, with specificity ranging from 68% to 100% and sensitivity from 71% to 100%. The rationale for employing these molecules as biomarkers lies in their potential biological roles, which encompass maintaining genomic stability through LINE-1 regulation, as well as direct involvement in critical processes such as cell cycle control, spindle assembly, and cellular adhesion—all of which are imperative for successful implantation. Full article

Background: The placenta plays a fundamental role in supporting fetal development, with angiogenesis being crucial for establishing an efficient maternal–fetal interface. Epigenetic mechanisms, particularly DNA methylation, can regulate the expression of angiogenesis-related genes and may be influenced by Assisted Reproductive Technology (ART), including In Vitro Fertilization (IVF) with fresh or frozen-thawed embryo transfer (ET and FET, respectively) and egg donation (ED), all potentially affecting placental vascular development and pregnancy outcomes. The present study compared global DNA methylation levels and the expression of Vascular Endothelial Growth Factor (VEGF), Placental Growth Factor (PlGF), and Soluble Fms-Like Tyrosine kinase-1 (sFlt-1) in placentae from physiological pregnancies obtained using ART versus those spontaneously conceived. Methods: Placental biopsies were collected from 98 physiological singleton term pregnancies (CTRL n = 29, ET n = 23, FET n = 25, ED n = 21). Global DNA methylation (5-mC) was quantified by ELISA Easy Kit; VEGF, PlGF, sFlt-1 mRNA and protein levels were assessed by Real-Time PCR and ELISA, respectively. Results: Global DNA methylation was significantly increased in FET and ED placentae compared with CTRL and ET. PlGF mRNA expression was upregulated in all ART groups, although protein levels were elevated only in ED placentae compared to CTRL and ET groups. VEGF mRNA was increased in FET placentae compared to CTRL, while protein levels showed a non-significant upward trend across ART groups. No differences in sFlt-1 expression were observed. Clinically, ART pregnancies were associated with significantly lower birth weight compared to CTRL, though values remained within the physiological range, and placental efficiency was preserved. Conclusions: Hypermethylation in FET and ED placentae may act as an epigenetic “buffer,” stabilizing vulnerable genomic regions and supporting the expression of pro-angiogenic factors. This adaptive mechanism likely helps to preserve placental function and fetal viability despite ART-related stressors, thereby mitigating the potential impact on birth weight. Full article

Objectives: This study aimed to determine whether chromosomal mosaicism in blastocysts is associated with a distinct morphokinetic signature. Methods: Preimplantation genetic testing for aneuploidy (PGT-A) was performed on 182 human embryos via trophectoderm biopsy on day 5 and analyzed by next-generation sequencing. Embryos were classified as euploid (n = 55), mosaic (n = 39: 21 low-grade, 18 high-grade), or aneuploid (n = 88), of which 18 with concurrent mosaicism. Prior to biopsy, embryos were cultured in a time-lapse system (EmbryoScope), and 12 morphokinetic parameters were assessed, including pronuclei fading (tPNf), cleavage times (t2–t9), morula formation (tM), blastulation start (tSB), and full blastocyst formation (tB). These parameters were compared according to ploidy status. Results: Patients with euploid and mosaic embryos were comparable in terms of maternal age, ART indication and embryo quality (p > 0.05). In contrast, aneuploid embryos were obtained from older patients and had lower morphological grades. Mosaic embryos showed delayed tPNf (24.8 ± 6.5 vs. 22.8 ± 2.3 h, p = 0.03) and t2 (27.6 ± 6.6 vs. 25.4 ± 2.5 h, p = 0.02) compared to euploid embryos, mainly attributable to low-grade mosaic embryos. Whole-chromosome mosaicism, but not segmental mosaicism, was associated with delayed embryo development at several intermediate cleavage time points (t3, t4, t6, t7 and t9). Aneuploid embryos showed significant delays at later stages versus euploid embryos, particularly aneuploid embryos with mosaicism at t7 (56.6 ± 8.3 vs. 52 ± 5.6 h, p = 0.02), t8 (59.1 ± 9.6 vs. 54.8 ± 6.7 h, p = 0.04), tM (90.3 ± 7.7 vs. 83.6 ± 8.2 h, p = 0.006) and tB (113.0 ± 11.6 vs. 106.6 ± 8.9 h, p = 0.03). Conclusions: Mosaic embryos exhibit delays in early development (tPNf, t2) but reach later morphokinetic milestones at rates similar to euploid embryos. In contrast, aneuploid embryos, especially those with mosaicism, exhibit marked developmental delays at later stages (t7, t8, tM, tB). Full article

Background/Objectives: The timing of blastocyst formation is an important factor in in vitro fertilization (IVF) outcomes. While many studies have shown similar pregnancy rates for euploid blastocyst transfers occurring on day 5 or 6, controversy remains, especially regarding patients with recurrent implantation failure (RIF). This study aimed to evaluate whether day 5 (D5) and day 6 (D6) euploid blastocysts differ in terms of the clinical outcomes achieved after frozen–thawed euploid embryo transfer, with subgroup analysis by maternal age in RIF patients. Methods: This retrospective analysis included a cohort of 514 patients who experienced RIF, categorized into two distinct groups: the initial group consisting of individuals who underwent embryo biopsy on day 5 (n = 456 euploid transfers) and the subsequent group comprising patients who underwent biopsy on day 6 (n = 58 euploid transfers) following ovum retrieval. These groups were utilized based on the completion of blastocyst development and the eventual pregnancy outcomes after the first post-frozen–thawed euploid embryo transfer confirmed by PGT-A. Results: Out of the total cohort of 514 RIF patients, 472 individuals were younger than 40 years of age, representing 91.8% of the sample population. The IVF process yielded successful positive pregnancy outcomes in 85.4% of the cases (439 out of 514)., and there was no statistically significant difference in maternal ages between the day 5 and day 6 biopsy cohorts (p = 0.286). The proportion of successful clinical pregnancies per transfer was markedly higher among those who underwent biopsy on day 5 in comparison to those subjected to biopsy on day 6 (79.2% vs. 58.6%, p = 0.002). In patients aged 35 years and younger who underwent biopsy on day 5, the rates of successful clinical pregnancy outcomes were superior to those who underwent biopsy on day 6 (79.8% vs. 56.5% p = 0.016). In individuals older than 35 years of age, no significant discrepancies in clinical pregnancy rates were observed between the two groups. Conclusions: Day 6 euploid embryo transfer was associated with lower clinical pregnancy rates per transfer compared with those on day 5, particularly in patients younger than 35 years of age. In women ≥ 35 years of age, outcomes did not differ significantly. These outcomes suggest that developmental timing interacts with maternal age in determining clinical outcomes. Further prospective studies with larger and more balanced cohorts are needed to confirm these findings. Full article

Embryo implantation requires a finely tuned immune balance at the maternal–fetal interface. Interferon tau (IFN-τ), a key immunomodulator in ruminant implantation, may have therapeutic potential in human reproduction. This study investigated its effects on peripheral blood mononuclear cells (PBMCs) in vitro and the subsequent impact on endometrial immune composition following intrauterine administration of these cells. The work was conducted in two stages. First, in vitro assays were performed with PBMCs from 20 patients with recurrent implantation failure (RIF) cultured with or without IFN-τ for 24 h. Cytokines (IL-10, IL-4, TNF-α, IL-6) were measured by ELISA, and T cell subsets (Th, cytT, Th1, Th2, Th9, Tfh, Th17, Treg) were analyzed by flow cytometry. IFN-τ increased IL-4 and reduced TNF-α and IL-6, indicating a Th2 profile shift. T-cell analysis revealed fewer cytT, Th1, Th9, and Th17 cells, more Th2 cells, and improved Th/Tk, Th1/Th2, and Th17/Treg ratios after IFN-τ. A second clinical study included 55 RIF patients who received intrauterine IFN-τ-modulated PBMCs. Post-treatment endometrial biopsies revealed more helper T cells and macrophages, with higher Th/total T, Th/cytT, and Th/macrophage ratios, suggesting a tolerogenic environment. Overall, IFN-τ modulates PBMCs in vitro and promotes a favorable endometrial immune profile in vivo, highlighting its potential as an immunotherapy in assisted reproduction. Full article

Preimplantation genetic testing for monogenic disorders (PGT-M) is a powerful tool for identifying genetic disorders prior to gestation. For hemoglobinopathies like thalassemias and sickle cell disease, PGT-M offers a preventative strategy to ensure that only embryos deemed genetically healthy are transferred. A comprehensive review of 22 original articles explores and summarizes the existing evidence on PGT-M techniques in hemoglobinopathies. The review focuses on key aspects such as accuracy, benefits, and drawbacks related to various hemoglobinopathies. Given the limited quantity of DNA obtained from an embryo biopsy, whole genome amplification (WGA) is a critical step for amplifying the sample. One of the available methods of WGA, multiple displacement amplification (MDA) is one of the most widely adopted method with acceptable allele drop-out (ADO) rates for hemoglobinopathies compared with traditional methods. Dealing with ADO constitutes a primary technical obstacle in PGT-M. The failure to amplify one allele in single-cell analysis is a major factor limiting the overall diagnostic accuracy of the procedure. To mitigate this issue, PCR-based and next-generation sequencing (NGS)-based approaches are employed. These methods incorporate linkage analysis with genetic markers such as short tandem repeats (STRs) or single-nucleotide polymorphisms (SNPs) to reduce the risk of incorrect interpretations from ADO and enhance the proportion of conclusive results. A future direction for PGT-M that involves the development of non-invasive methods (niPGT) will be included and discussed. Full article

Background: Recurrent pregnancy loss (RPL) and recurrent implantation failure (RIF) are significant challenges in reproductive medicine. For both, embryonic aneuploidy is the leading etiological factor. Preimplantation genetic testing for aneuploidy (PGT-A) via trophectoderm biopsy is the current standard for embryo selection. However, it is limited by its invasiveness, potential for embryo damage, and diagnostic errors due to mosaicism. Rationale/Objectives: This review critically evaluates the emerging role of noninvasive PGT (niPGT). NiPGT analyzes cell-free DNA from spent blastocyst culture media, thus, it is a potential alternative for managing RPL and RIF. Hence, the primary objective is to determine whether current evidence supports niPGT as a reliable replacement for conventional biopsy-based PGT-A in these high-risk populations. Outcomes: The analysis reveals that niPGT offers significant theoretical advantages. These include complete non-invasiveness, enhanced embryo preservation, and high patient acceptability. However, its clinical application is hampered by substantial limitations. Key amongst them is the inconsistent and often suboptimal diagnostic accuracy (sensitivity 70–85%, specificity 88–92%) compared to biopsy. Other significant factors include the high rates of amplification failure (10–50%), vulnerability to maternal DNA contamination, as well as low DNA yield. Crucially, there is a definitive lack of robust, prospective randomized controlled trial (RCT) data demonstrating improved live birth rates or reduced miscarriage rates specifically in RPL and RIF cohorts. As such, niPGT is not yet ready to be a standalone clinical adoption in RPL and RIF cases. However, it may serve as a valuable adjunct for rescue scenarios following biopsy failure or for ethical reasons. Wider Implications: The integration of niPGT with artificial intelligence, time-lapse imaging, and multi-omics profiling underlies a promising future. However, its transition from a predominantly research tool to a clinical standard necessitates various critical undertakings. These include rigorous multicenter RCTs, standardizing international protocol, and tailoring validation for the RPL and RIF subgroups. This review highlights the need for cautious optimism, positing that evidence-based integration, rather than premature adoption, is essential to realizing niPGT’s full potential without compromising patient care in these complex fertility scenarios. Full article