Abstract
Selecting embryos with the highest developmental potential remains a decisive step for achieving successful in vitro fertilization outcomes. Conventional evaluation methods such as morphological grading, time-lapse imaging, and preimplantation genetic testing for aneuploidy provide valuable information but are limited by subjectivity, invasiveness, and cost. These challenges have driven increasing interest in non-invasive biomarkers capable of improving the precision and safety of embryo assessment. Emerging evidence indicates that human embryos actively release microRNAs into their surrounding environment, particularly into the spent culture medium and blastocoel fluid. These extracellular microRNAs regulate pathways involved in cell cycle progression, apoptosis, differentiation, and embryo-endometrium communication. Distinct expression signatures, including miR-21-5p, miR-661, and members of the miR-17∼92 cluster, correlate with chromosomal integrity and implantation competence, suggesting their potential as complementary or alternative biomarkers to trophectoderm biopsy. Comparative analyses across digital PCR, quantitative RT-PCR, microarray, and next-generation sequencing platforms reveal both methodological advances and unresolved challenges, such as low RNA yield, contamination risk, and inconsistent normalization strategies. Embryo-derived microRNAs thus represent a promising avenue for non-invasive embryo evaluation, with future clinical translation hinging on robust multicenter validation and integration with imaging, metabolomics, and artificial intelligence–based analytics.
1 Introduction
In assisted reproductive technology (ART), embryo selection remains one of the most crucial determinants of IVF success, directly influencing implantation and live birth rates. Traditional methods, such as morphological grading and time-lapse imaging, provide useful morphological insights but have limited predictive accuracy and cannot reliably distinguish euploid from aneuploid embryos (; ; ). Preimplantation genetic testing for aneuploidy (PGT-A) offers direct chromosomal assessment and has improved selection efficiency; however, it is invasive, costly, and occasionally discordant with the embryo’s true genetic state due to mosaicism (; ; ). These limitations have prompted the search for non-invasive biomarkers that can complement or even replace invasive testing. Among the candidates, microRNAs (miRNAs) have recently attracted considerable attention. MiRNAs are short, non-coding RNA molecules (∼22 nucleotides) that regulate gene expression post-transcriptionally by targeting messenger RNAs, thereby controlling essential cellular processes such as proliferation, apoptosis, and differentiation (). Importantly, preimplantation embryos secrete miRNAs into their surrounding microenvironment, including spent culture medium (SCM) and blastocoel fluid (BF), making these molecules accessible for non-invasive analysis ().
Several studies have reported variable expression of embryo-derived miRNAs associated with chromosomal status and implantation potential. For example, certain miRNA signatures detected in spent culture medium (SCM) have been correlated with blastocyst viability and developmental competence (; ; ) while profiling of BF has revealed distinct expression patterns related to chromosomal abnormalities (). Despite these promising findings, significant challenges remain, including low RNA yield, contamination from maternal cells or culture reagents, and the absence of standardized analytical protocols (; ). Therefore, a comprehensive synthesis of current evidence is warranted to clarify the clinical potential of embryo-secreted miRNAs. Relevant literature was identified through searches in PubMed, Scopus, and Web of Science (supplemented by manual searches in Google Scholar). The search covered January 2014 to September 2025 and included studies focusing on embryo-derived microRNAs in spent culture medium, blastocoel fluid, or trophectoderm biopsy associated with aneuploidy, embryo viability, or implantation outcomes. After screening and eligibility assessment, 42 studies were included in this review.
This review aims to summarize the role of embryo-secreted miRNAs as non-invasive biomarkers of embryo viability and chromosomal integrity, highlight recent methodological advances, and outline future directions toward their integration into routine IVF practice.
2 Sources of embryo-secreted microRNAs
MicroRNAs (miRNAs) from the embryo have been discovered to be secreted from a variety of biological compartments associated with in vitro fertilization (IVF), providing a range of non-invasive research opportunities (). Spent culture medium (SCM) and blastocoel fluid (BF), which are direct secretions from the developing embryo, are two sources that have been widely explored (; ; ). Additional sources, such as trophectoderm (TE) biopsy samples, follicular fluid, and endometrial or uterine fluid, have also been explored, though these are either invasive or indirectly reflect embryo physiology (; ; ). The relative invasiveness and diagnostic value of these biological sources are illustrated in Figure 1.
FIGURE 1
2.1 Spent culture medium (SCM)
Embryos, as living organisms, are capable of secreting and releasing a variety of biological molecules, including microRNAs (miRNAs), into their surrounding culture medium. Several studies have demonstrated that the miRNA profile in spent culture medium (SCM) is linked to blastocyst morphology, developmental competence, and implantation potential. Therefore, determining the miRNA pattern in spent culture medium (SCM) can be used as a non-invasive biomarker to assess embryo quality in vitro fertilization (IVF) processes (; ). However, the amount of RNA released into the culture medium is very low, which makes its extraction and accurate identification challenging. On the other hand, the possibility of sample contamination with RNA from peripheral cells, such as cumulus cells surrounding the oocyte or embryo, as well as compounds present in laboratory reagents, can lead to inaccurate or ambiguous results. Therefore, the precise isolation of embryo-specific miRNAs from other sources must be carefully performed to ensure reliable analyses (). Different biological sources of embryo-secreted miRNAs, together with their main advantages, limitations, and clinical relevance, are summarized in Table 1.
TABLE 1
| Source | Advantages | Limitations | Clinical evidence/Reported associations | Type of evidence/Study design |
|---|---|---|---|---|
| Spent culture medium (SCM) | Direct secretion from embryos; non-invasive; easy to collect during IVF culture | Low RNA yield; risk of contamination from maternal cells or culture reagents | Associations with blastocyst morphology, embryo viability, implantation and pregnancy outcomes reported across multiple studies | Observational cohort studies; targeted miRNA profiling (qRT-PCR/microarray) |
| Blastocoel fluid (BF) | Enriched in extracellular vesicles and miRNAs; closely reflects embryo physiology | Extremely small volume; technically challenging extraction and analysis | Distinct miRNA profiles reported between euploid and aneuploid blastocysts; associations with implantation potential | Observational comparative studies (euploid vs. aneuploid embryos) |
| Trophectoderm (TE) biopsy | Provides molecular validation; gold standard for chromosomal assessment | Invasive; not suitable as a routine non-invasive biomarker | Widely used for PGT-A; confirms molecular patterns observed in SCM and/or BF | Clinical diagnostic studies (PGT-A-based analyses) |
| Follicular fluid | Reflects oocyte microenvironment; miRNAs involved in oocyte maturation and fertility | Mixed maternal and oocyte origin; limited embryo specificity | Altered miRNA profiles associated with PCOS and infertility-related conditions | Observational studies in infertility populations |
| Endometrial/uterine fluid | Non-invasive sampling; provides insight into implantation environment | Mixture of maternal and embryonic signals; limited specificity for embryo origin | miRNA profiles linked to endometrial receptivity and implantation success | Exploratory observational studies; receptivity-focused analyses |
Sources of embryo-derived microRNAs: key advantages, limitations, and level of clinical evidence.
For SCM, and BF, current evidence is largely observational and exploratory, highlighting the need for standardized protocols and prospective clinical validation before routine clinical application.
2.2 Blastocoel fluid (BF)
During blastocyst development, the blastocoel cavity enlarges, and the fluid within it contains extracellular vesicles enriched with miRNAs. These vesicles play a crucial role in cellular signaling and gene expression regulation during early embryonic development, indicating the presence of complex regulatory mechanisms that are initiated by the embryo (; ; ). Studies have shown that miRNA profiles in BF can show significant differences between euploid and aneuploid embryos. These differences imply the potential of BF to provide reliable and non-invasive biomarkers for the detection of chromosomal status and embryo competence (; ). While the extraction and analysis of miRNA and DNA from blastocoel fluid (BF) is challenging due to the small sample size and the need for sensitive and precise methods, with the advancement of molecular technologies, this pathway has been proposed as a new strategy in assisted reproductive technology (ART) to improve the selection of high-quality embryos and increase the implantation success rate ().
2.3 Trophectoderm (TE) biopsy
Trophectoderm (TE) biopsy is used for preimplantation genetic testing (PGT-A). Although it is an invasive procedure, it remains the gold standard for genetic health screening and detection of chromosomal abnormalities in IVF (; ). Some studies have shown that microRNA and mRNA can be extracted from trophectoderm samples, and specific molecular patterns associated with aneuploidy and implantation success can be identified (). This provides important biological evidence in confirming embryo-derived microRNAs detected in non-invasive samples such as blastocoel fluid (BF) or culture medium. This means that molecular findings from TE biopsy provide biological validity to data obtained from less invasive samples (). However, TE biopsy itself, due to its invasive nature, cannot replace non-invasive methods in clinical practice ().
2.4 Other sources
Follicular fluid is the environment in which the oocyte grows and develops and contains a collection of microRNAs. These miRNAs regulate gene expression in various pathways that control oocyte maturation, health, and fertility (; ). In diseases such as polycystic ovary syndrome, the microRNA profile in follicular fluid is altered, which can lead to reduced oocyte quality (). In addition, the cumulus cells that surround the oocyte also produce and secrete microRNAs and extracellular vesicles containing these RNAs, which act as molecular messengers for communication with the oocyte and help regulate signaling pathways related to oocyte growth, maturation, and fertilization (). Endometrial fluid is another important source of microRNAs that provide the uterine environment for embryo implantation. miRNAs in this fluid may play a role in the regulatory processes of implantation and embryo maintenance in the uterus; changes in the expression of these miRNAs may affect implantation success and pregnancy health (). While these fluids provide valuable insights into the reproductive microenvironment, they represent a mixture of maternal and embryonic contributions, which limits their specificity as embryo-derived biomarkers (; ). Nevertheless, these non-embryo-specific sources may hold promise in multi-omics strategies that integrate both embryonic and maternal signals for a more comprehensive assessment of implantation potential ().
3 miRNAs and chromosomal aneuploidy
Recent research has highlighted embryo-secreted microRNAs as promising indicators of chromosomal status (; ; ). reported that miR-191 levels were increased in the culture medium of aneuploid embryos. This miRNA has been associated with activation of the PI3K/AKT and MAPK pathways in other cellular models, suggesting a possible role in promoting cell survival and reducing apoptosis, which may allow chromosomally abnormal embryos to persist rather than undergo natural elimination. (). reported differential expression of miR-661 and miR-20a between euploid and aneuploid blastocysts in blastocoel fluid (BF) (). In addition, reported specific miRNAs, such as miR-21-5p and miR-661, in spent culture media that were linked not only to embryo developmental potential but also suggested a possible link to chromosomal constitution (). Studies suggest that miR-20a plays an important role in G1/S progression by modulating the E2F/Cyclin D1 axis; its increased expression may lead to accelerated and insufficient passage through cell-cycle checkpoints (). miR-661 has been linked to reduced cell adhesion and induction of epithelial-mesenchymal transition (EMT) in several cellular models, reflecting cellular instability and stress responses that may parallel chromosomal imbalance in embryos (). In addition, miR-21-5p may influence apoptosis-related signaling by targeting PTEN and modulating the PI3K/AKT pathway, as reported in other cellular contexts, which could support cell survival in embryos with chromosomal abnormalities ().
Also, in their systematic review, reported that miR-19b, miR-517c, miR-518e, miR-522, miR-92a, and miR-106a were consistently downregulated in aneuploid blastocysts, reinforcing the significant association between miRNA patterns and chromosomal errors (). Among these, miR-19b, miR-92a, and miR-106a are members of the miR-17∼92 family, which has been suggested to regulate cell-cycle progression by modulating Cyclins and CDKs, as well as TGF-β and Wnt signaling pathways. Reduced expression of these miRNAs may impair checkpoint control and contribute to irregular chromosomal segregation (). analyzed trophectoderm biopsies and showed that miR-30c and miR-372 were downregulated in aneuploid blastocysts. miR-30c has been suggested to modulate the Wnt/β-catenin pathway involved in blastocyst development and differentiation, and its reduced expression may disrupt the coordination of cell division. On the other hand, miR-372, which belongs to the RAS/MAPK and TGF-β signaling axes, has been suggested to participate in maintaining the pluripotency of embryonic cells. Its reduced expression in aneuploid embryos may indicate a loss of the natural balance between pluripotency and differentiation (). The embryo-secreted microRNAs associated with chromosomal aneuploidy and checkpoint dysregulation are shown in Figure 2. Key miRNAs implicated in aneuploidy, their signaling pathways, and reported biological effects are listed in Table 2.
FIGURE 2
TABLE 2
| miRNA | Primary pathway/Target | Functional role/Biological effect | Supporting references |
|---|---|---|---|
| miR-191 | PI3K/AKT, MAPK | Promotes cell survival, inhibits apoptosis → persistence of abnormal embryos | ; |
| miR-661 | EMT, cell adhesion | Reduces cell adhesion and promotes instability; marker of cellular stress and aneuploidy | ; ; |
| miR-21-5p | PTEN/PI3K/AKT | Anti-apoptotic; enhances survival of chromosomally abnormal embryos | ; |
| miR-20a | E2F/Cyclin D1 axis | Dysregulated G1/S transition → abnormal cell division and chromosomal missegregation | ; |
| miR-19b, miR-92a, miR-106a (miR-17∼92 cluster) | Cyclins/CDKs, TGF-β, Wnt | Regulate cell-cycle checkpoints; downregulation causes segregation errors in aneuploidy | ; |
| miR-30c | Wnt/β-catenin | Controls blastocyst differentiation; reduced expression disrupts cell-division coordination | |
| miR-372 | RAS/MAPK, TGF-β | Maintains pluripotency; downregulation leads to imbalance between pluripotency and differentiation |
Key embryo-derived miRNAs associated with aneuploidy and their biological pathways.
4 miRNAs and implantation potential
Successful implantation depends on a complex interplay between embryo competence and endometrial receptivity. Even chromosomally normal embryos may fail to implant due to inadequate molecular signaling or impaired embryo–endometrium crosstalk (; ). Recent studies suggest that microRNAs (miRNAs) secreted by embryos and present in maternal reproductive fluids may serve as biomarkers of implantation potential (; ).
demonstrated that human embryos release miR-191 into the culture medium and that its levels are associated with implantation outcomes. This miRNA has been linked to activation of the PI3K/AKT and MAPK pathways, which promote cell survival and inhibit apoptosis, potentially supporting the persistence of embryos capable of implantation (). In addition, showed that miRNAs in blastocoel fluid (BF) are connected to the Wnt/β-catenin and RAS/MAPK pathways and that changes in their expression can disrupt the balance between pluripotency and differentiation and affect implantation capacity ().
reported that high-quality embryos secrete miR-320a, this miRNA enhances the migration of endometrial stromal cells (hESCs) and prepares the receptive field for implantation through cytoskeletal rearrangement and activation of genes related to cell motility (). identified three miRNAs—miR-199a-5p, miR-483-5p, and miR-432-5p—in the spent culture medium (SCM) of human embryos, whose expression was associated with successful implantation. Pathway analysis suggested that these miRNAs were involved in cell-cycle regulation and apoptosis, indicating their potential as markers of blastocyst growth and viability (). analyzed more than 60 blastocysts and detected 53 distinct miRNAs. Eight miRNAs, including miR-191-5p, miR-320a, miR-92a-3p, miR-509-3p, miR-378a-3p, miR-28-3p, miR-512-5p, and miR-181a-5p, showed the strongest association with implantation outcomes. Pathway enrichment analysis indicated that these miRNAs are involved in PI3K/AKT, MAPK/ERK, cell-cycle, and survival pathways, suggesting that their coordinated activity may influence implantation potential (). Recently, compared miRNAs derived from blastocoel fluid (BF) and spent culture medium (SCM), revealing distinct expression patterns between the two sources. Some miRNAs specific to spent culture medium (SCM) were associated with endometrial receptivity, adhesion, and invasion pathways ().
Additionally, studies have shown that uterine fluid miRNA profiles are disrupted in women with recurrent implantation failure, suggesting a disruption in the embryo-endometrial communication (). Similarly, specific miRNA expression in endometrial fluid can non-invasively identify an implanting (receptive) endometrium (). In addition, distinct plasma miRNA patterns during the preimplantation period are associated with biochemical pregnancy loss after embryo transfer, reinforcing the role of systemic signaling of miRNAs in early pregnancy outcomes (). However, the molecular overlap between implantation-related miRNAs and those linked to general embryo stress complicates their interpretation. For example, reported that miR-21-5p (among others) is involved in both stress/inflammatory pathways and implantation-associated signaling, highlighting this overlap(). A schematic representation of the main embryo and endometrium-derived miRNAs and their signaling interactions during implantation is shown in Figure 3. miRNAs associated with implantation potential, their roles, and sample origins are presented in Table 3.
FIGURE 3
TABLE 3
| miRNA | Source/Sample | Main pathway/Function | Role in implantation | Supporting references |
|---|---|---|---|---|
| miR-191 | Spent culture medium (SCM) | PI3K/AKT, MAPK | Promotes embryo survival and implantation competence through anti-apoptotic signaling | |
| miR-320a | Spent culture medium (SCM) | Cytoskeletal and migration genes | Secreted by high-quality embryos; enhances migration of endometrial stromal cells and receptivity | |
| miR-199a-5p | SCM | Cell-cycle, apoptosis regulation | Associated with successful implantation and improved blastocyst development | |
| miR-483-5p | SCM | Apoptosis regulation | Positively correlates with embryo viability and implantation outcome | |
| miR-432-5p | SCM | Cell-cycle progression | Marker of developmental competence and implantation success | |
| miR-92a-3p | Blastocoel fluid/SCM | PI3K/AKT, MAPK | Strongly linked to implantation outcome; participates in survival and adhesion pathways | |
| miR-509-3p | Blastocoel fluid | PI3K/AKT | Correlated with implantation success; may regulate embryo–endometrium crosstalk | |
| miR-378a-3p | Blastocoel fluid | MAPK/ERK | Contributes to cellular proliferation and differentiation supporting implantation | |
| miR-28-3p | Blastocoel fluid | Cell-cycle control | Associated with embryo quality and implantation potential | |
| miR-512-5p | Blastocoel fluid | TGF-β/survival | Positively linked to implantation competence | |
| miR-181a-5p | Blastocoel fluid | MAPK, cell adhesion | Supports embryo–endometrial communication and trophoblast invasion | |
| miR-21-5p | Endometrium/plasma | PTEN/PI3K/AKT | Dual role in stress and implantation; modulates inflammatory and apoptotic responses | ; |
| miR-21-5p, miR-661 | SCM/BF | Endometrial receptivity and adhesion | Indicate implantation competence; involved in invasion and attachment processes | ; |
| miR-191-5p, miR-320a, miR-92a-3p | SCM/BF | PI3K/AKT, MAPK, cell-cycle | Co-regulated network supporting implantation success | ; |
| Uterine fluid miRNAs (various) | Uterine fluid | Receptivity pathways | Dysregulated in recurrent implantation failure | |
| Endometrial fluid miRNAs (various) | Endometrial fluid | Implantation receptivity | Identify receptive vs. non-receptive endometrium |
Key microRNAs associated with implantation potential.
5 Methods of miRNA profiling in IVF
Accurate detection and quantification of embryo-derived microRNAs in non-invasive samples such as spent culture medium (SCM) or blastocoel fluid (BF) remain challenging because of the extremely low RNA content and limited sample volume (). To overcome these limitations, several analytical platforms have been developed, each offering distinct advantages and constraints. Among them, qRT-PCR remains the most widely used because of its high sensitivity, specificity, and relatively low cost. This approach enables detailed analysis of known miRNAs but has limited capacity to identify novel or low-abundance species (). Microarray technology allows simultaneous screening of hundreds of miRNAs and offers broader coverage than qRT-PCR, although its lower sensitivity and background hybridization noise can affect data quality (). Next-generation sequencing (NGS) provides the most comprehensive overview, enabling unbiased discovery of known and novel miRNAs, detection of isoforms, and identification of sequence variants. However, it requires specialized bioinformatics expertise, high-quality input material, and remains expensive. Building on these approaches, digital PCR (dPCR) has recently been introduced for absolute quantification of embryo-derived miRNAs, offering higher precision than conventional qRT-PCR (). Although not yet widely adopted in reproductive medicine, dPCR shows strong potential for rapid and clinically scalable applications ().
Regardless of the platform used, challenges such as low RNA extraction efficiency, risk of contamination, lack of consensus on normalization, and absence of standardized laboratory protocols still hinder reproducibility and inter-study comparisons (; ). Overall, developing standardized procedures for isolation, quantification, and analysis of miRNA data is a key prerequisite for integrating these technologies into routine IVF practice. The advantages, limitations, and recommended applications of the major miRNA profiling methods are summarized in Table 4.
TABLE 4
| Method | Advantages | Limitations | Typical applications in IVF research | Current clinical readiness |
|---|---|---|---|---|
| qRT-PCR | Very high sensitivity and specificity; relatively low cost; widely available instruments; short turnaround time | Limited to known miRNAs; low throughput; depends on normalization strategy | Targeted quantification and validation of candidate miRNAs in SCM or BF | Research and targeted validation |
| Microarray | Simultaneous screening of hundreds of miRNAs; broader coverage than qRT-PCR | Lower sensitivity for low-abundance miRNAs; cross-hybridization; semi-quantitative | Exploratory and comparative studies (e.g., euploid vs. aneuploid embryos) | Discovery-phase only |
| Next-generation sequencing (NGS) | Unbiased detection of known and novel miRNAs; identification of isoforms and sequence variants; comprehensive profiling | High cost; complex library preparation; requires advanced bioinformatics expertise; longer turnaround time | Biomarker discovery; comprehensive miRNA landscape characterization | Discovery-phase only |
| Digital PCR (dPCR) | Absolute quantification; very high precision and sensitivity for low-abundance targets; minimal dependence on reference genes | Limited availability; higher cost per assay; not yet standardized for IVF samples | Rapid quantification of selected miRNA panels; potential same-cycle embryo assessment | Near-clinical translational potential |
Comparison of methods for profiling embryo-derived microRNAs in IVF.
While qRT-PCR, remains the most commonly used platform in IVF-related miRNA, studies, emerging technologies such as dPCR, offer improved precision and faster turnaround times, making them promising candidates for future clinical implementation following multicenter validation and standardization.
6 Limitations and challenges
Although microRNAs have emerged as promising non-invasive biomarkers for assessing embryo viability and chromosomal status, several obstacles still prevent their entry into routine use in IVF. Embryo-derived miRNAs are present at extremely low levels, often near the detection limits of current assays (; ; ). Variability in RNA extraction efficiency, reverse transcription, and amplification introduces technical noise and compromises reproducibility (). Spent culture medium (SCM) and blastocoel fluid (BF) are often contaminated by maternal cells, sperm remnants, or culture reagents, so distinguishing embryo-specific miRNAs from background signals therefore remains a critical challenge (; ).
Studies employ different RNA isolation kits, input volumes, and normalization strategies. This heterogeneity limits comparability across studies, thereby preventing meta-analysis (). Embryo-to-embryo heterogeneity and developmental stage–specific expression patterns further complicate interpretation (). Moreover, some miRNAs associated with aneuploidy or implantation failure overlap with stress-induced miRNAs, undermining specificity (). Most studies to date have small sample sizes and lack prospective validation (). Consequently, predictive accuracy remains moderate, and no consensus panel of miRNAs has yet been established. The integration of miRNA testing into IVF workflows would require robust, rapid, and cost-effective assays. Current technologies, such as NGS, are costly and time-consuming, thus posing barriers to clinical translation ().
6.1 Normalization challenges in embryo-derived miRNA studies
Normalization of miRNA expression in embryo culture samples remains a key limitation when comparing results across studies. Variations in RNA extraction yield, reverse transcription efficiency, and amplification bias can introduce significant error, especially given the extremely low RNA content of embryo-derived media. Some researchers use exogenous spike-ins, such as cel-miR-39, to adjust for technical differences, while others rely on endogenous reference miRNAs, including miR-16 or miR-191, that appear relatively stable in preimplantation settings. For example, evaluated miR-16, miR-191, and miR-106 as stable references for preimplantation mouse embryos (). In addition, several studies have applied global mean or multi-gene normalization strategies supported by algorithms like NormFinder and geNorm to improve reproducibility. Achieving consensus on standardized normalization approaches will be essential for future clinical translation of embryo-secreted miRNA analyses.
7 Future directions
Future research should prioritize the development of standardized protocols for sample collection, RNA isolation, normalization strategies, and data interpretation to improve reproducibility across embryo-derived microRNA studies. The lack of harmonized methodologies remains a major barrier to cross-study comparison and clinical translation, underscoring the need for consensus-driven technical guidelines (; ).
Prospective, multicenter clinical studies with adequately powered cohorts are essential to validate candidate miRNA panels and to establish clinically actionable thresholds for embryo selection (; ). Such validation frameworks will be critical for distinguishing biologically meaningful signals from stress-related or culture-induced miRNA expression.
Technological advances, particularly digital PCR and microfluidic-based platforms, offer promising opportunities for rapid and sensitive detection of low-abundance embryo-secreted miRNAs and may enable same-cycle embryo assessment in IVF laboratories (; ). In parallel, integrating miRNA profiling with complementary modalities such as time-lapse imaging, metabolomics, and artificial intelligence–based modeling may enhance predictive accuracy beyond single-parameter approaches (; ).
Finally, the translation of miRNA-based embryo assessment tools into routine IVF practice should be guided by robust regulatory frameworks and ethical oversight to ensure embryo safety, data integrity, and equitable clinical implementation ().
8 Conclusion
Accumulating evidence indicates that embryos actively secrete microRNAs into their surrounding environment, particularly into spent culture medium and blastocoel fluid, and that distinct miRNA signatures are associated with chromosomal status and implantation potential. These findings highlight embryo-derived miRNAs as promising non-invasive biomarkers that may complement existing embryo assessment strategies. However, current evidence remains largely observational, and technical challenges, including low RNA yield, contamination risk, and lack of standardized protocols, limit immediate clinical implementation. Continued methodological refinement and large-scale validation will be essential to define the clinical utility of miRNA-based embryo evaluation in IVF.
Statements
Author contributions
ME: Visualization, Writing – original draft, Methodology, Conceptualization, Investigation, Writing – review and editing. MN-E: Conceptualization, Writing – review and editing, Supervision.
Funding
The author(s) declared that financial support was not received for this work and/or its publication.
Acknowledgments
All scientific content, analyses, and interpretations were fully conceived and performed by the authors.
Conflict of interest
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Summary
Keywords
aneuploidy, embryo selection, implantation, IVF, microRNA, non-invasive biomarkers
Citation
Esmaeilivand M and Nasr-Esfahani MH (2026) Embryo-secreted microRNAs enable non-invasive assessment of chromosomal status and viability in in vitro fertilization. Front. Cell Dev. Biol. 13:1747211. doi: 10.3389/fcell.2025.1747211
Received
15 November 2025
Revised
10 December 2025
Accepted
16 December 2025
Published
05 January 2026
Volume
13 - 2025
Edited by
Antonio Diez Juan, Vitrolife, Sweden
Reviewed by
Claudia Omes, San Matteo Hospital Foundation (IRCCS), Italy
Arwa Almutlaq, King Saud University, Saudi Arabia
Updates
Copyright
© 2026 Esmaeilivand and Nasr-Esfahani.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Masoumeh Esmaeilivand, m.esmaeilivand@gmail.com
Disclaimer
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