JBRA Assist. Reprod. 2026 2026;00(0):00-00
REVIEW
doi: 10.5935/1518-0557.20260107
1Graduate Program in Cellular and Molecular Biology Applied to Health, Lutheran University of Brazil (ULBRA). Canoas, Rio Grande do Sul, Brazil
CONFLICT OF INTEREST
The authors declare that they have no competing interests.
Abstract
Fragile X syndrome is a monogenic disorder caused by the expansion of CGG trinucleotide repeats in the fragile X mental retardation 1 (FMR1) gene and is a major cause of inherited intellectual disability and reproductive impair-ment. Preimplantation genetic testing for monogenic disor-ders (PGT-M) has become an important strategy in assisted reproduction to prevent the transmission of FMR1-related disorders. This narrative review aimed to summarize cur-rent evidence on the molecular basis, technical approaches, clinical outcomes, and challenges associated with PGT-M for FMR1 CGG repeat expansions. A literature search was performed in the PubMed database, including English-lan-guage original studies, clinical investigations, and reviews. The reviewed studies demonstrate that advances in multi-plex PCR, linked-marker analysis, and next-generation se-quencing have significantly improved diagnostic accuracy, overcoming earlier limitations related to CGG repeat analy-sis, allele dropout, and mosaicism. Although women carry-ing FMR1 premutations frequently present with diminished ovarian reserve and reduced response to ovarian stimula-tion, pregnancy and live birth rates per embryo transfer are comparable to those of non-carriers when individual-ized stimulation protocols are applied. The combined ap-plication of PGT-M and Preimplantation Genetic Testing for Aneuploidy may be considered in selected clinical scenarios to optimize embryo selection, although indications should be individualized. In addition to its clinical benefits, PGT-M raises ethical, psychological, and economic considerations, emphasizing the importance of genetic counseling in re-productive decision-making. Overall, PGT-M represents a safe and effective tool in assisted reproduction for couples at risk of transmitting FMR1 related disorders, with grow-ing relevance in clinical practice and public health.
Keywords: preimplantation genetic testing, monogenic diseases, FMR1, fragile X syndrome, human reproduction
INTRODUCTION
Fragile X syndrome (FXS) is a monogenic disorder characterized by neurodevelopmental impairments. It affects approximately 1 in 4,000 males and 1 in 8,000 females, with intellectual disability and autism spectrum disorder (ASD) as its main clinical outcomes (Salcedo-Arellano et al., 2020). In individuals with FXS, the underlying molecular alteration is the expansion of a polymorphic CGG repeat in the 5′ untranslated region (5′ UTR) of the fragile X mental retardation 1 (FMR1) gene. Full mutation alleles (>200 CGG repeats) are typically associated with hypermethylation of the FMR1 promoter region, leading to transcriptional silencing and absence or severe reduction of the fragile X mental retardation protein (FMRP), which characterizes FXS. In contrast, premutation alleles (55-200 CGG repeats) remain transcriptionally active and are associated with elevated FMR1 mRNA levels, resulting in RNA-mediated cellular toxicity that underlies premutation-associated disorders such as fragile X associated tremor/ataxia syndrome (FXTAS) and fragile X associated primary ovarian insufficiency (FXPOI) (Haham et al., 2018). Although FXS is the most recognized clinical manifestation, premutation alleles of the FMR1 gene are also clinically relevant. These are linked to clinical conditions that manifest later, during adulthood, such as FXTAS and FXPOI (Kumari & Usdin, 2020). In a Brazilian study, 52 patients diagnosed with premature ovarian insufficiency who were followed at an infertility clinic were evaluated. Mutations in the FMR1 gene were identified in 3.8%, and the most frequently observed allele sizes were 28 and 30 CGG repeat alleles (Ramos et al., 2022).
Studies have demonstrated that premutation carriers (≥55 CGG repeats) may transmit alleles with an increased number of CGG repeats to their offspring. Risk estimates for expansion to a full mutation are primarily based on the maternal CGG repeat number and family history assessment. Although it is not possible to accurately predict the exact magnitude of repeat expansion from one generation to the next, the probability of CGG repeat expansion is well established and warrants careful clinical consideration (Nolin et al., 2015).
The instability of CGG repeat expansions in the FMR1 gene represents a central biological mechanism underlying transmission risk in fragile X associated disorders. The presence and number of AGG interruptions within the CGG repeat tract exert a stabilizing effect and may modify the probability of repeat expansion during maternal transmission. From a clinical perspective, this variability directly influences the assessment of reproductive risk and highlights the importance of individualized genetic counseling rather than relying solely on CGG repeat size for risk estimation (Nolin et al., 2015). Thus, accurate molecular characterization contributes not only to diagnostic classification but also to informed reproductive decision making and appropriate expectation management for affected couples.
Expansion beyond 200 CGG repeats leads to methylation of the FMR1 promoter region and transcriptional silencing of the gene, resulting in reduced or absent levels of the FMRP. Deficiency of FMRP promotes the persistence of immature neuronal phenotypes and reduced neuroplasticity, which can impair cognitive function and learning abilities (Ranjan et al., 2023). FMRP is an RNA-binding protein that regulates the translation of a specific subset of messenger RNAs that shuttle between the nuclear and cytoplasmic compartments and associates with polyribosomes during translation (Dokras & Barlow, 2022; Liu et al., 2023).
In this context, preimplantation genetic testing (PGT) has become increasingly relevant and can be applied to monogenic disorders (PGT-M), chromosomal structural rearrangements (PGT-SR), and aneuploidy detection (PGT-A). Currently, preimplantation genetic testing involves extended embryo culture to the blastocyst stage, followed by biopsy of multiple trophectoderm cells rather than a single blastomere at the cleavage stage. The biopsied material undergoes whole genome amplification (WGA), allowing reliable downstream genetic analysis while preserving embryonic developmental potential (De Rycke & Berckmoes, 2020; Fesahat et al., 2020). Genetic diagnosis in contemporary PGT-M relies on a combined strategy including direct detection of the pathogenic variant together with linkage or haplotyping analysis using short tandem repeats (STRs) or single nucleotide polymorphisms (SNPs), thereby reducing diagnostic errors such as allele dropout and recombination events (Ogilvie et al., 2005; Kieffer et al., 2016). Strict laboratory quality control procedures, including contamination monitoring and amplification assessment, are essential to ensure diagnostic accuracy and reliability when analyzing limited embryonic DNA samples obtained during PGT-M (Chen et al., 2018). Despite the high diagnostic accuracy achieved with contemporary PGT-M approaches, confirmatory prenatal testing through procedures such as chorionic villus sampling or amniocentesis is generally recommended during pregnancy to validate the embryonic genetic diagnosis, in accordance with current clinical guidelines (Ethics Committee of the American Society for Reproductive Medicine, 2018). The development and validation of family specific informational tests using samples from affected first degree family members currently offer high accuracy rates (Dokras & Barlow, 2022). Despite significant advances in PGT-M technologies, diagnostic interpretation remains influenced by technical limitations such as allele dropout, recombination events, and potential contamination. Strategies including linkage analysis and haplotyping approaches are essential to mitigate these risks and increase diagnostic accuracy and reliability. Understanding these limitations is fundamental during pre-test counseling, as residual uncertainty may influence the number of embryos available for transfer and clinical decision-making throughout assisted reproduction treatment cycles. In parallel, it is estimated that approximately 2-4% of couples of reproductive age are at risk of conceiving a child with an autosomal recessive or X-linked genetic disorder, underscoring the clinical relevance of preimplantation genetic testing strategies (Capalbo et al., 2021).
Several studies suggest that only a narrow range of CGG repeats (26-34 repeats) in the FMR1 gene represents the truly normal interval and is associated with adequate expression of the FMRP (Schuettler et al., 2011; Noto et al., 2016). In contrast, alleles classified as “high-normal” (35-54 CGG repeats) and “low-normal” (<26 CGG repeats) have been associated with reduced protein expression levels and an increased risk of reproductive alterations, including diminished ovarian reserve, primary ovarian insufficiency, and polycystic ovary syndrome, which may ultimately contribute to infertility. Despite these observations, the available literature shows inconsistent and sometimes conflicting results regarding the association between the number of CGG repeats in the FMR1 gene and ovarian reserve (Gleicher et al., 2012; 2015; Pastore et al., 2014; Maslow et al., 2016). Consequently, the clinical relevance of mutations in the FMR1 gene in women with idiopathic infertility remains controversial and has not yet been fully established, indicating the need for further well designed studies to clarify this relationship. In this context, the present review aimed to describe the use of the PGT-M testing and the clinical outcomes of patients with alterations in the FMR1 gene.
MATERIALS AND METHODS
This study was conducted as a narrative literature review aimed at summarizing current evidence regarding FMR1 gene alterations, FXS, and the clinical application of PGT-M in assisted reproduction.
A literature search was performed in the PubMed database to identify relevant publications. The last search was conducted in November 2025. The search strategy included combinations of the following terms: (“FMR1” OR “fragile X syndrome”) AND (“preimplantation genetic testing” OR “PGT-M”) AND (“assisted reproduction” OR “human reproduction”). Articles published in English were considered eligible. Included studies comprised original research articles, clinical studies, and review articles addressing molecular mechanisms, reproductive implications, laboratory methodologies, or clinical outcomes related to FMR1 alterations and PGT-M. Studies not directly related to reproductive genetics, PGT or FMR1-associated conditions were excluded.
Study selection was performed through screening of titles and abstracts, followed by full-text evaluation based on relevance to the objectives of this review. In addition, the reference lists of relevant articles were manually screened to identify additional studies of potential relevance. Evidence was qualitatively synthesized through thematic analysis, focusing on molecular mechanisms, technical approaches, reproductive outcomes, and current clinical challenges associated with the application of PGT-M in reproductive medicine. Given the narrative nature of this review, no formal risk-of-bias assessment or quantitative meta-analysis was performed.
Molecular Aspects of Preimplantation Genetic Testing for Monogenic Diseases (PGT-M)
Appropriate implementation of PGT-M requires a clear definition of the mutant alleles that may be transmitted to the offspring of couples undergoing in vitro fertilization (IVF) in combination with this technique. Given the heterogeneity of mutation types and gene structures, the genotyping strategy used in PGT-M must be individualized for each couple to accurately detect the pathogenic variant of interest (Chen et al., 2018). Accordingly, pre-PGT-M testing is recommended prior to initiating IVF cycles to improve the accuracy and reliability of the PGT-M assay. This preparatory step typically requires DNA samples from both parents and, in some cases, from additional family members to enable informative haplotyping and reliable mutation tracking (Fesahat et al., 2020). PGT-M involves the biopsy and genetic analysis of embryonic cells prior to implantation, allowing the identification of known familial pathogenic variants. Based on these results, only embryos that are free of the mutation of interest are selected for transfer to the uterine cavity, thereby reducing the risk of transmitting inherited genetic disorders (Zou et al., 2024). For a considerable period, the application of PGT-M for FXS was limited by the low informativeness of CGG repeat analysis, particularly in cases in which the normal allele of the female carrier was identical in size to the allele of the male partner, thereby compromising accurate allele discrimination (Platteau et al., 2002). Subsequent methodological advances have been developed in analytical approaches to overcome these limitations. Notably, the multiplex assay described by Kieffer et al. (2016) incorporates five novel, highly polymorphic FMR1-linked SSRs, resulting in substantial improvements in diagnostic accuracy. The high heterozygosity of these markers increases overall test informativeness compared with previously described FMR1-linked markers, while the co-amplification of normal CGG repeats and informative microsatellites within a single PCR reaction further enhances diagnostic reliability in informative couples. These methodological advances have minimized the risk of discarding potentially healthy embryos due to inconclusive or inaccurate diagnoses and have contributed to improved clinical success rates among couples undergoing PGT-M for FXS, particularly in clinical settings with a limited number of embryos available for analysis, such as women carrying FMR1 premutations associated with FXPOI (Persico et al., 2023).Currently, PGT-M protocols for FMR1-related disorders rely on a multiplex polymerase chain reaction approach designed to detect expanded FMR1 alleles through the simultaneous amplification of multiple informative polymorphic markers located within approximately 1 Mb of the FMR1 CGG repeat region (Persico et al., 2023). The use of fluorescent multiplex PCR enables the incorporation of linked markers into the analysis, thereby minimizing technical limitations inherent to PCR analysis of limited embryonic DNA samples, such as allele dropout and contamination, and improving overall diagnostic robustness (Ogilvie et al., 2005).Although embryonic mosaicism represents a major interpretative challenge in preimplantation genetic testing, particularly in PGT-A, the principal diagnostic risks in PGT-M arise primarily from technical factors such as allele dropout, recombination events, DNA contamination, and phasing errors. Consequently, linkage analysis and haplotyping strategies constitute essential components of contemporary PGT-M protocols to increase diagnostic accuracy and reliability (De Rycke & Berckmoes, 2020; Hu et al., 2021). Given that embryonic aneuploidy represents an important factor influencing implantation failure and miscarriage, the use of PGT-A may be considered in selected clinical scenarios, such as advanced maternal age or recurrent implantation failure, with the aim of supporting embryo selection. However, indications for PGT-A should be individualized, and genetic counseling should address the potential benefits, limitations, and ongoing uncertainties regarding clinical outcomes in specific patient populations (Capalbo et al., 2021; Ethics Committee of the American Society for Reproductive Medicine, 2018).
Use of Preimplantation Genetic Testing for Mono-genic Diseases (PGT-M)
In 1990, Handyside and colleagues were the first to report live births achieved through IVF followed by PGT for an X-linked disorder (Handyside et al., 1990). Since then, PGT has been widely adopted as a diagnostic tool for a broad spectrum of monogenic disorders, enabling the birth of unaffected children worldwide (Tur-Kaspa et al., 2014). Over recent decades, advances as well as challenges in PGT-M have driven multidisciplinary collaboration to broaden its clinical applications; however, multiple technical, ethical, and clinical issues remain to be carefully considered (Dokras & Barlow, 2022). Each year, the number of monogenic conditions eligible for testing continues to increase. Concurrently, analytical methods have become more robust, and the indications for PGT-M have expanded to include applications such as human leukocyte antigen (HLA) typing and the use of PGT-M for late-onset disorders (Ogilvie et al., 2005; Chantrasiri et al., 2025; Schadwell et al., 2025).The application of PGT-M is particularly relevant in reproductive medicine, as genetic alterations are frequently associated with infertility and adverse reproductive outcomes. Many fertile individuals who elect to undergo screening for monogenic disorders do so after experiencing the termination of affected pregnancies, highlighting a preventive rather than fertility-driven indication for testing (Gianaroli et al., 2003). Among the primary motivations for pursuing PGT-M are the desire to conceive an unaffected child, a history of recurrent miscarriages, prior pregnancy termination due to fetal abnormalities, and the presence of affected children or relatives within the family (Lee et al., 2020). Despite its established clinical value, PGT-M remains underutilized in neurological and psychiatric practice, as neurologists and clinical psychiatrists infrequently discuss this option with patients. Consequently, relatively few individuals seek genetic counseling or actively inquire about PGT-M, underscoring a gap between advances in reproductive genetics and their integration into routine clinical care (Zou et al., 2024).Among the challenges associated with PGT-M from the patient perspective, the procedure is often described as costly and psychologically demanding, underscoring the need for comprehensive genetic and reproductive counseling throughout the decision-making process. From the standpoint of fertility centers, additional challenges include the need to individualize diagnostic strategies for each case while managing the inherent difficulties of reproductive cycles that may yield no transferable embryos, particularly in patients with compromised reproductive potential (Zanetti et al., 2019). Although the overall number of reproductive cycles incorporating PGT-M remains relatively low, its utilization is expected to increase along with the expansion of preconception genetic screening and growing awareness of this technology. Importantly, available evidence suggests that pregnancy outcomes following embryo transfer in PGT-M cycles are reassuring across all maternal age groups, supporting the clinical feasibility and safety of this approach (Chada et al., 2022). Despite the high diagnostic accuracy achieved with PGT-M, confirmatory prenatal testing through procedures such as chorionic villus sampling or amniocentesis is generally recommended to validate the embryonic genetic findings during pregnancy and ensure diagnostic concordance (Ethics Committee of the American Society for Reproductive Medicine, 2018).Evidence indicates that the role of PGT-M extends beyond the prevention of severe inherited disorders, as it may also contributing to the reduction of miscarriage risk. Ethical considerations surrounding the use of PGT-M have been widely discussed, particularly with respect to the non-transfer of affected embryos, a practice that may be associated with reduced emotional distress and is often perceived as ethically more acceptable than prenatal diagnosis followed by pregnancy termination. Furthermore, the possibility of adult-onset or chronic genetic conditions, which frequently entail long-term medical care and substantial healthcare costs, leads many couples to regard the initial financial burden of PGT-M as a relatively smaller and justified investment within their reproductive planning (Ethics Committee of the American Society for Reproductive Medicine, 2018).
PGT-M for Fragile X Syndrome
The primary limitation of PGT-M in FMR1-related disorders concerns female patients carrying premutations, who are at increased risk of primary ovarian insufficiency and frequently exhibit a reduced response to ovarian stimulation. Nevertheless, comparable pregnancy and live birth rates per embryo transfer have been reported in this population when compared with non-carriers, supporting the feasibility of PGT-M in appropriately selected cases (Persico et al., 2023). In addition, emerging evidence indicates that carriers of full FMR1 mutations may also experience varying degrees of ovarian insufficiency, further complicating reproductive planning (Tsafrir et al., 2010). Considering these risks, fertility preservation strategies should be discussed early with affected women. Specifically, oocyte cryopreservation has been recommended for premutation carriers as a proactive approach to preserve reproductive potential, particularly given the elevated risk of primary ovarian insufficiency associated with FMR1 alterations (Sonigo et al., 2021).Carriers of the FMR1 premutation have been shown to exhibit a reduced ovarian response compared with individuals carrying the full mutation. Consistently, women with the FMR1 premutation tend to present elevated baseline follicle-stimulating hormone (FSH) levels, a finding indicative of diminished ovarian reserve (Wittenberger et al., 2007; Avraham et al., 2017). As a result, premutation carriers are generally considered poor responders to exogenous gonadotropin stimulation, which may limit the number of embryos available for PGT-M analysis. However, evidence from a retrospective cohort study suggests that this limitation may be partially mitigated. Selected FMR1 premutation carriers have demonstrated an ovarian response comparable to that of individuals carrying the full mutation when higher total doses of FSH are administered, supporting the use of individualized ovarian stimulation protocols to compensate for reduced ovarian reserve and enable a response similar to that observed in individuals carrying the full mutation (Ranisavljevic et al., 2020).In Israel, preconception genetic screening for the FMR1 is offered free of charge to all women of reproductive age. FMR1 premutation carriers with more than 70 CGG repeats or a family history of FXS are eligible for IVF combined with PGT-M. Evidence from a retrospective cohort study indicates that many women opted for PGT-M primarily because of a history of pregnancy termination related to FXS and advanced maternal age. In contrast, patients who had previously undergone unsuccessful IVF cycles often chose not to pursue additional IVF attempts with PGT-M (Haham et al., 2018).In China, a long-term review of PGT-M implementation over the past 24 years has highlighted the growing relevance of this technology, particularly given the country’s high burden of genetic diseases. The expansion of PGT-M has been associated with substantial benefits, not only for individual and public health, but also from an economic perspective, by reducing the long-term costs associated with inherited disorders (Liu et al., 2023). Furthermore, evidence from clinical studies suggests that women carrying non-mutated FMR1 alleles within the high-normal range (35-54 CGG repeats) may experience altered IVF outcomes, including a reduced number of live births, underscoring the clinical relevance of FMR1 CGG repeat length even outside the premutation range (Zhou et al., 2022).
Reproductive Pathways and Decision-Making Fol-lowing Unsuccessful In Vitro Fertilization
Women carrying FMR1 premutations (55-200 CGG repeats) present specific reproductive challenges that directly influence assisted reproduction strategies and clinical decision making. Genetic counseling plays a central role in aligning reproductive expectations with the biological limitations associated with FMR1-related ovarian dysfunction. In this context, counseling should integrate molecular genetic information, embryological outcomes, and reproductive prognosis, since the success of assisted reproduction combined with PGT-M depends not only on embryo genetic status but also on ovarian response, embryo developmental competence, and the likelihood of obtaining transferable embryos. These aspects should be discussed prior to treatment initiation to establish realistic expectations regarding the possible need for multiple stimulation cycles, variable reproductive outcomes, and the potential for treatment failure despite appropriate clinical and laboratory management.Female premutation carriers are at increased risk of FXPOI, a well-established reproductive manifestation of the FMR1 premutation, with approximately 20-30% of carriers developing premature ovarian insufficiency, particularly among individuals with 80-100 CGG repeats. The premutation has been associated with RNA-mediated toxic effects that disrupt ovarian function, contributing to accelerated ovarian aging, diminished ovarian reserve, and reduced oocyte yield during controlled ovarian stimulation (Huang et al., 2019). As a consequence, unsuccessful IVF cycles in these patients may reflect rapidly declining ovarian reserve and may require timely reproductive decision making.In clinical practice, premutation carriers frequently present poor ovarian response, characterized by low estradiol levels and a limited number of retrieved oocytes compared with age matched controls. Because of the reduced oocyte yield, multiple stimulation cycles may be necessary to accumulate embryos for PGT-M (Haham et al., 2018). However, even when embryos are obtained, the number of transferable embryos may remain limited. In addition to reduced oocyte numbers, embryos derived from premutation carriers may harbor unstable CGG repeats that can expand to a full mutation (>200 repeats) during transmission. Therefore, the application of PGT-M to identify embryos without pathogenic expansion may substantially reduce the number of embryos considered suitable for transfer, further limiting reproductive success (Streuli et al., 2009).These biological and genetic constraints have important implications for cycle planning and patient expectations, since treatment may require repeated stimulation cycles and may still result in cycles without transferable embryos. Early reproductive planning is therefore particularly relevant for premutation carriers. Fertility preservation strategies, including oocyte or embryo cryopreservation, may be considered when ovarian reserve remains adequate, ideally soon after identification of the premutation (Streuli et al., 2009).When ovarian reserve becomes severely compromised or repeated cycles fail to generate transferable embryos, donor oocytes or donor embryos may represent appropriate reproductive alternatives. The use of donor gametes not only increases the probability of pregnancy but also eliminates the risk of transmitting the FMR1 mutation to offspring, which may be an important consideration for affected couples (Noto et al., 2016).Overall, reproductive counseling for FMR1 mutation carriers should integrate genetic risk assessment, ovarian prognosis, and individualized reproductive planning in order to support informed clinical decision making and patient centered reproductive care.
CONCLUSION
Preimplantation genetic testing for monogenic disorders (PGT-M) has become an important strategy in assisted reproduction for couples carrying pathogenic variants associated with inherited conditions such as FXS. By enabling the selection of embryos unaffected by the causative mutation prior to implantation, PGT-M offers a preventive reproductive approach that reduces the risk of transmitting genetic disease to offspring. Because FXS follows an X linked inheritance pattern, female carriers have a 50 percent probability of transmitting the mutation to each child, whereas affected or carrier males transmit the mutation to all daughters and to none of their sons (Finucane et al., 2012). In this context, the incorporation of PGT-M into IVF protocols represents a clinically relevant option for couples seeking to prevent the transmission of FMR1 related disorders.
Compared with conventional prenatal diagnosis, which identifies genetic abnormalities during pregnancy, PGT-M allows reproductive decision making before embryo transfer, thereby avoiding the psychological burden that may arise when a genetic diagnosis is established during gestation. Nevertheless, the use of embryo biopsy and genetic selection raises ethical considerations and requires careful discussion with patients. For this reason, genetic counseling remains a fundamental component of clinical care, ensuring that couples understand the benefits, limitations, and ethical implications associated with the use of PGT-M.
Women carrying FMR1 premutations represent a particularly challenging clinical group in assisted reproduction. These patients frequently present diminished ovarian reserve and an increased risk of fragile X associated primary ovarian insufficiency, which may reduce oocyte yield and limit the number of embryos available for genetic testing. Consequently, treatment strategies often require individualized planning that integrates ovarian prognosis, genetic transmission risk, and the potential need for alternative reproductive options.
Taken together, the available evidence supports several key clinical implications for reproductive specialists and laboratory teams:
• FMR1 premutation carriers present unique reproductive challenges, including reduced ovarian reserve and an increased risk of FXPOI, which may limit embryo availability during IVF cycles.Overall, the integration of molecular genetics, reproductive medicine, and specialized counseling is critical to improving clinical outcomes and guiding reproductive planning for couples affected by FMR1 related disorders.
• PGT-M represents a valuable strategy to prevent transmission of the FMR1 mutation, although clinicians should recognize that diagnostic constraints and limited embryo numbers may influence treatment outcomes.
• Decisions regarding the combination of PGT-M with additional genetic testing strategies should be individualized, taking into account patient characteristics, ovarian response, and reproductive prognosis.
• Multidisciplinary genetic counseling involving clinicians, embryologists, and genetic specialists remains essential to support informed reproductive decision making and optimize patient centered care.
Acknowledgements:
This study was supported by the Lutheran University of Brazil (ULBRA), Coordination for the Improvement of Higher Education Personnel (CAPES; Finance Code 001), Brazil.
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