Search Results (260)

Background: Preimplantation genetic testing for polygenic diseases (PGT-P) is a reproductive technology that has made it possible to assign risk scores to embryos for various complex polygenic conditions such as diabetes, hypertension, breast cancer, and schizophrenia. Whether there is public interest in utilizing PGT-P and what public opinions are regarding this technology is unknown. Therefore, the objective of our study was to evaluate the opinion of the general United States (US) public regarding PGT-P. Methods: A web-based questionnaire consisting of 25 questions was administered to a nationally representative sample of adult US residents according to age and sex. The survey contained a description of PGT-P, followed by questions with Likert-scale responses ranging from strongly agree to strongly disagree. Results: Of the 715 respondents recruited, 673 (94%) completed the survey. Most respondents agreed that use of PGT-P is ethical (54%), and another 37% were neutral; however, approximately 9% of respondents disagreed and were opposed to the use of PGT-P. Those that opposed PGT-P cited that it was “unethical” (46%) or “not natural” (39%), believed children could be negatively affected (31%), or stated that it went against their religion (15%). The majority of respondents did not know whether PGT-P was safe for embryos (68%) or children (67%) and felt that anyone should be able to utilize it (53%). Conclusions: Participants who were younger, were Atheist, or were Democrats were more likely to agree that “PGT-P is ethical”. This study identified that more than half of respondents supported the use of PGT-P. However, concerns regarding its safety and ethical implications persist. Full article

Background/Objectives: Embryo selection in IVF is traditionally based on morphology, yet many high-quality embryos fail to implant. Preimplantation genetic testing for aneuploidy (PGT-A) using next-generation sequencing (NGS) has been proposed to improve selection by identifying euploid embryos. However, its effectiveness in women of advanced maternal age remains unclear due to limited randomized data. This pilot trial assessed the feasibility of a full-scale RCT comparing PGT-A to morphology-based selection in women aged 35–42. Methods: This single-centre, two-arm parallel RCT (NCT05009745) enrolled women aged 35–42 undergoing IVF/ICSI with ≥3 good-quality day-3 embryos. Participants were randomized (1:1) to either embryo selection by morphology with fresh transfer or PGT-A with frozen transfer of a single euploid embryo. Allocation concealment was achieved via a secure web-based randomization platform; patients and clinicians were unblinded, but the biostatistician remained blinded. The primary outcome was feasibility of recruitment, randomization, and adherence. Results: Between June 2021 and January 2023, 138 women consented (recruitment rate: 55.8%, 95% CI: 49.7–62.0%) and 100 were randomized. Protocol adherence was 94%. Barriers to recruitment included preference for private PGT-A (19%) or fresh transfer (6%). Among biopsied embryos, 51.4% were euploid and 6.6% low-level mosaic. Intention-to-treat analysis showed no significant differences between PGT-A and control groups in clinical pregnancy rate (50% vs. 40%), live birth rate (50% vs. 38%), or miscarriage rate (12% vs. 8%). Cumulative live birth rate after up to three SETs was 72% vs. 52%, respectively (p > 0.05). No multiple pregnancies occurred. Conclusions: RCTs of PGT-A in older women are feasible. A multicentre design with broader inclusion criteria could improve recruitment and allow better assessment of clinical benefit. Full article

Bovine serum albumin (BSA), the most commonly used protein in preimplantation embryo culture media, performs a variety of physiological functions. However, its involvement in long-term effects remains largely unclear. To investigate its physiological importance in culture media, we examined the developmental and metabolic consequences of BSA deprivation during preimplantation stages in mice. Embryos cultured in BSA-free media during specific time windows exhibited impaired blastocyst formation, with continuous deprivation from the two-pronuclei (2PN) stage significantly reducing trophectoderm (TE) and inner cell mass (ICM) cell numbers (p < 0.05), indicating compromised viability. Short-term BSA deprivation similarly disrupted lineage allocation, underscoring the sensitivity of early embryos to nutrient availability during cell fate determination. Although birth rates remained unaffected, suggesting compensatory mechanisms, longitudinal analysis revealed sex-specific metabolic dysfunction. Male offspring developed progressive glucose intolerance by 16 weeks, exhibiting elevated fasting glucose levels (p < 0.05) and impaired glucose clearance, whereas females showed no significant alterations in glucose metabolism. This study demonstrates that protein restriction during the preimplantation period not only disrupts early embryonic development but also programs long-term metabolic dysfunction, underscoring the importance of optimizing culture conditions in assisted reproductive technologies to minimize future health risks. Full article

This study presents the first successful generation and comprehensive characterization of trophoblastic organoids (TOs) and the derivation of three-dimensional cavity- or sac-like structures—termed lacunoids/cystoids—from sheep intracytoplasmic sperm injection (ICSI) embryos. TOs were generated from sheep ICSI embryos for the first time and were shown to express trophoblastic markers at levels comparable to those in embryonic tissue. Detailed morphological characterization was conducted for both the TOs and the derived lacunoids/cystoids. Additionally, the TOs’ interactions with endometrial organoids (EOs), as well as those with preimplantation embryos, were investigated through co-culture experiments. The TOs expressed key trophoblastic markers, including CDX2, GATA3, syncytin-1, KRT18, KRT7, and Sox2, confirming their validity as a model for studying sheep trophoblast biology. The generation of lacunoids/cystoids from the TOs further revealed their structural and developmental characteristics, contributing valuable insights into early placental development and trophoblast-related pathologies. The TOs also supported extended embryonic development, and their co-culture with EOs induced dynamic changes in gene expression, particularly in angiogenesis-related genes, in both organoid types. This novel and reproducible in vitro model offers a reliable platform to study early placental development, effectively recapitulating the biological crosstalk between the trophectoderm and endometrium. The in-depth characterization of TOs and lacunoids/cystoids highlights their potential to advance our understanding of trophoblast differentiation and related developmental disorders. Full article

Oxidative stress poses a challenge to in vitro embryo culture. As a flavonoid, galangin (GAL) has been shown to have antioxidant effects, but the effect and antioxidant capacity of GAL in the in vitro development of porcine parthenogenetic embryos are still unknown. In this study, we demonstrated that 1 µM GAL significantly increased the blastocyst rate, decreased the accumulation of intracellular reactive oxygen species (ROS), increased the glutathione (GSH) level, and enhanced mitochondrial function in early porcine embryos. Nuclear factor erythroid-2-related factor 2 (Nrf2) was identified as the target gene of GAL via network pharmacology, and the transcript levels of related antioxidant enzymes (HO-1, NQO1, SOD2, and CAT) were found to be increased. Since Nrf2 has seven domains, we constructed Nrf2 mutants lacking different domains in vitro. We found that GAL specifically binds to the Neh1 domain of Nrf2. Subsequent embryonic experiments demonstrated that the antioxidant effect of GAL was abolished after Nrf2 deletion. These results suggest that GAL can directly bind to Nrf2 to regulate the level of oxidative stress and improve mitochondrial function in embryos. Full article

Assisted reproduction technology (ART) has advanced significantly over the past four decades, leading to improved pregnancy outcomes and a reduction in complications, particularly those associated with multiple pregnancies. These improvements largely stem from advances in understanding embryonic physiology, which has enabled better culture conditions. As a result, embryologists can now efficiently culture embryos to the blastocyst stage and successfully cryopreserve them for future use. However, while incubators aim to replicate the maternal environment of the oviduct and uterus, embryos in vitro are cultured in static conditions, unlike the dynamic, constantly changing environment they experience in vivo. Key factors such as pH, temperature, osmolality, and gas concentrations are crucial for establishing optimal embryo development and implantation potential. Moreover, the vitrification procedure for gametes or embryos can introduce oxidative stress, as well as osmotic shock and cryoprotectant toxicity, which may affect embryo viability and increase the risk of birth defects. Since the first successful ART birth in 1978, over 10 million babies have been conceived through these techniques. Although most of these children are healthy, concerns exist about potential birth defects or changes linked to the handling of gametes and embryos. The preimplantation period is marked by significant epigenetic reprogramming, which can be influenced by ART procedures such as ovarian stimulation, in vitro fertilization, embryo culture, and cryopreservation. However, the long-term health implications for offspring remain uncertain. Epigenetic reprogramming during early embryogenesis is essential for proper embryo development and can be changed by ART-related conditions. These concerns have raised questions about the possible connection between ART and a higher risk of birth defects or other changes in children born through these methods. Therefore, we conducted a scoping review following PRISMA-ScR guidelines to map evidence on ART-related risks, including epigenetic and birth defect outcomes. Full article

Background: Charcot–Marie–Tooth disease (CMT) is a genetically and clinically heterogeneous group of progressive peripheral neuropathies. Preimplantation genetic testing for monogenic disorders (PGT-M), a well-established assisted reproductive technology used to detect specific genetic mutations in embryos before implantation, has been used in common CMT subtypes (e.g., CMT1A); however, data on its application across rarer subtypes and in de novo cases remain limited. In this study, we aimed to evaluate the effectiveness of PGT-M using karyomapping in achieving clinical pregnancies and healthy births in families affected by various CMT types, including the previously unreported subtypes CMT1B and CMT2. Methods: We analyzed 31 PGT-M cycles from 13 families with genetically confirmed CMT, including cases of previously unreported subtypes CMT1B and CMT2. A total of 150 embryos were biopsied. Through 19 embryo transfer cycles, 21 embryos were transferred. In one de novo case, karyomapping was performed using amniotic fluid from an affected fetus as a reference. Results: Of the 19 embryo transfers, 15 resulted in clinical pregnancies. Prenatal diagnosis confirmed that all fetuses were unaffected, and all pregnancies resulted in healthy live births. Successful phasing using amniotic fluid from an affected fetus enabled accurate embryo selection and led to the birth of healthy twins. Conclusions: PGT-M using karyomapping is a rapid and reliable method for achieving successful pregnancies in families affected by diverse CMT subtypes, including de novo cases, and supports broader applicability to other monogenic disorders. Full article

Background/Objectives: Preimplantation genetic screening improves embryo selection in intracytoplasmic sperm injection cycles, especially for women of advanced maternal age. As chromosomal normality declines with age, high-dose gonadotropins are commonly used to enhance follicular response. This study compares minimal and high-dose stimulation protocols in terms of euploidy, pregnancy, and live birth rates following single embryo transfer. Methods: In this prospective study, 198 women aged 38–45 years were enrolled and divided into two groups: minimal stimulation (100 mg clomiphene citrate and 75 IU human menopausal gonadotropin) and high stimulation (300–450 IU gonadotropins). Women with severe male factor infertility, endometriosis, or absolute tubal factor were excluded. Clinical outcomes were compared using a t-test or Mann–Whitney U test. Results: Baseline characteristics were similar between groups. The high-dose group had a significantly higher number of retrieved oocytes (p = 0.009) and metaphase II oocytes (p = 0.003). However, there were no significant differences in euploid embryo rates (35.4% vs. 37.4%, p = 0.768), clinical pregnancy rates (67.6% vs. 69.4%, p > 0.999), gestational sac rates (58.8% vs. 58.3%, p > 0.999), or live birth rates (47.1% vs. 50.0%, p = 0.995). Conclusions: This is the first prospective study to compare euploid embryo rates, pregnancy rates, and live birth rates between minimal stimulation protocol and high stimulation protocol in AMA patients. Although there has been no difference in euploid and pregnancy rates, minimal stimulation protocol has advantages in cost and comfort. Full article

Preimplantation genetic testing (PGT) has been used in various forms over the last two decades. PGT involves testing early embryos following in vitro fertilization and has now become an accepted part of genetic testing. Nowadays, PGT serves as a resource for couples who have a family history of monogenic disorders, wherein the fetus is at high risk of inheriting the condition. PGT is also used to improve pregnancy outcomes in IVF patients in cases of recurrent IVF implantation failure, recurrent miscarriages, as well as male factor. It is also used in screening for sex-linked disorders and sourcing stem cells for therapy. The latest PGT direction is polygenic embryo screening (PES, PGT-P), which allows the identification of embryos that are at elevated risk for significant diseases in adulthood, such as coronary artery disease (CAD), diabetes, hypertension, and breast cancer. As the prevalence and the potential for the use of PES grow, fundamental ethical issues have been underlined, raising concerns about the broader implications of genetic testing. This narrative review summarizes indications, methods, applications, and limitations for PGT, with a particular focus on PES. Full article

Preimplantation genetic testing for aneuploidy (PGT-A) is widely used to select euploid embryos for in vitro fertilization (IVF), but its accuracy in predicting the implantation potential for full segmental aneuploid (Seg-A) embryos remains unclear. In this study, we investigated chromosomal concordance between clinically biopsied trophectoderm (TE) and inner cell mass (ICM) in 175 donated blastocysts, which comprised those clinically diagnosed as euploid (13), Seg-A (36), segmental mosaicism (Seg-M) (60), whole-chromosome aneuploid (Who-A) (52), and whole-chromosome mosaicism (14). Using next-generation sequencing (NGS), we found that TE–ICM concordance rates were higher for euploid (85%) and Who-A (94%) embryos but significantly lower for Seg-A (25%) and Seg-M embryos (33%). For Seg-A, the euploidy rate in the ICM was 19% and the euploidy rate in the ICM was 63% for Seg-M. These low concordance rates may be due to technical and biological artifacts of PGT-A for Seg-A. Despite the significant discordance between TE and ICM, a subset of Seg-A embryos demonstrated euploidy. While clinically diagnosed euploid embryos remain the preferred choice, Seg-A embryos should be considered as having implantation potential. In particular, Seg-A results should be clearly distinguished from Who-A results and not routinely categorically discarded. Further research is required to refine the selection criteria, aided by parental karyotyping or re-biopsy, and to develop more reliable embryo assessment methods to ensure the accurate evaluation of reproductive potential and support shared decision making between doctors and patients. Full article

Background and Objectives: This meta-analysis aimed to determine whether pre-implantation uterine artery (UtA) Doppler measurements are associated with clinical pregnancy in women undergoing assisted reproductive technologies (ART). Materials and Methods: A systematic search of MEDLINE, Scopus, and the Cochrane Library from inception until 25 March 2025 was conducted to identify relevant studies. Additional records were retrieved through grey literature searching and manual reference checks. Eligible publications were observational studies or clinical trials that evaluated UtA Doppler indices prior to embryo transfer in adult women undergoing ART. Studies were required to report on clinical pregnancy rates, while those enrolling participants under 18 years of age, lacking Doppler data, or providing no pregnancy endpoints were excluded. Three reviewers independently assessed study quality using the Newcastle–Ottawa Scale and the Quality in Prognosis Studies tool. Meta-analyses were performed using a random-effects model to calculate mean differences (MDs) with 95% confidence intervals (CIs). Heterogeneity was examined via Cochran’s Q and the I² statistic. Sensitivity analyses excluded studies at high risk of bias. Results: In total, 12 studies met the inclusion criteria, including a population of 3317 women. Women who achieved clinical pregnancy had a lower mean UtA pulsatility index (PI) (MD, −0.26; 95% CI, −0.46 to −0.06) and a higher peak systolic velocity (PSV) (MD, 8.59; 95% CI, 2.31 to 14.87) than those who did not conceive. Subgroup analyses showed that UtA PI measured during the menstrual cycle was lower in clinical pregnancy cases (MD, −0.38; 95% CI, −0.66 to −0.10). Measurements on the day of hCG administration or the day before showed a non-significant difference in UtA PI (MD, −0.43; 95% CI, −1.03 to 0.17), while assessments on the day of embryo transfer showed no significant difference between groups (MD, −0.02; 95% CI, −0.28 to 0.24). Conclusions: This meta-analysis suggests that lower UtA PI and higher PSV prior to embryo transfer are associated with higher clinical pregnancy rates in ART, particularly when measurements are taken during the menstrual cycle. Although these findings highlight a potential role for uterine hemodynamics in successful clinical pregnancy, UtA Doppler alone may not be a reliable predictor. Future studies should focus on earlier-cycle Doppler measurements and their integration into multifactorial models to improve prognostic accuracy. Full article

There are two types of noninvasive biomarkers of human embryo developmental potential: those based on a direct assessment of embryo morphology over time and those using spent media after embryo in vitro culture as source of information. Both are derived from previously acquired knowledge on different aspects of pre-implantation embryo development. These aspects include embryo morphology and kinetics, chromosomal ploidy status, metabolism, and embryonic gene transcription, translation, and expression. As to the direct assessment of morphology and kinetics, pertinent data can be obtained by analyzing sequential microscopic images of in vitro cultured embryos. Spent media can serve a source of genomic, metabolomic, transcriptomic and proteomic markers. Methods used in the early pioneering studies, such as microscopy, fluorescence in situ hybridization, autoradiography, electrophoresis and immunoblotting, or enzyme-linked immunosorbent assay, are too subjective, invasive, and/or time-consuming. As such, they are unsuitable for the current in vitro fertilization (IVF) practice, which needs objective, rapid, and noninvasive selection of the best embryo for uterine transfer or cryopreservation. This has been made possible by the use of high-throughput techniques such as time-lapse (for direct embryo evaluation), next-generation sequencing, quantitative real-time polymerase chain reaction, high-performance liquid chromatography, nanoparticle tracking analysis, flow cytometry, mass spectroscopy, Raman spectroscopy, near-infrared spectroscopy, and nuclear magnetic resonance spectroscopy (for spent culture media analysis). In this review, individual markers are presented systematically, with each marker’s history and current status, including available methodologies, strengths, and limitations, so as to make the essential information accessible to all health professionals, even those whose expertise in the matter is limited. Full article

Embryogenesis and tumorigenesis share several key biological characteristics, such as rapid cell proliferation, high plasticity, and immune evasion. This similarity indicates that developmental pathways can be hijacked, leading to the formation of malignant cell states. With regard to this, cancer can be regarded as a stem cell disease. On the contrary, a fetus, in many ways, has similar characteristics to the “ideal tumor”, such as immune evasion and rapid growth. Therefore, deciphering the molecular mechanisms beneath these phenomena will help us to understand the embryonic origins of cancer. This review discusses the relationship between embryogenesis and tumorigenesis, highlighting the potential roles played by DUX4. DUX4 is involved in the activation of the zygote genome and then facilitates the establishment of totipotency in pre-implantation embryos, whereas the misexpression of DUX4 is associated with different types of cancer. Taken together, this indicates that DUX4 performs analogous functions in these two processes and connects embryogenesis and tumorigenesis. Through examining DUX4, this review underscores the importance of developmental mechanisms in cancer biology, suggesting that the insights gained from studying embryonic processes may provide novel therapeutic strategies. As we continue to explore the complex relationship between cancer and embryogenesis, elucidating the role of DUX4 in linking these two processes will be critical for developing targeted therapies that exploit developmental pathways. Full article

Background/Objectives: Male infertility is becoming a serious problem affecting about 7% of all men worldwide and is a major or contributory factor in 50% of infertile couples overall. Men with abnormal semen parameters have a significantly increased risk of aneuploidy, presenting a serious concern in programmes of assisted reproductive technologies. Recently, the introduction of preimplantation genetic testing for aneuploidies (PGT-A) has increased the pregnancy rate and live births. We investigated the effect of PGT-A on the success of IVF treatment in couples with the male factor of infertility. Methods: Two experimental groups and one control group were studied: Group A (110 couples)—male partners with abnormal semen parameters, with PGT-A; Group B (110 couples)—male partners with abnormal semen parameters, without PGT-A; and Group C (105 couples)—control, male partners with normal spermograms, with PGT-A. A Day 3 blastomere biopsy was followed by FISH-based PGT-A. A total of 880 embryos from Group A and 890 embryos from Group C was analysed. Results: In patients with abnormal semen parameters, embryonic aneuploidy was twice as common compared to the control (13.6% vs. 5.8%, p < 0.001). Group B had the lowest clinical pregnancy rate (28.2%), with two out of three pregnancies ending in a miscarriage. Only 10% of IVF cycles in this group resulted in live birth compared with 35.5% for Group A and 49.5% for Group C. Conclusions: Our data demonstrate that PGT-A screening as part of IVF treatment drastically increases the clinical pregnancy rate and chances of live birth in couples where male partners have semen abnormality. Full article

To minimise the influence of chromosomal abnormalities during IVF treatment, embryos can be screened before transfer using preimplantation genetic testing. This typically involves an invasive trophectoderm biopsy at the blastocyst stage, where 4–8 cells are collected and analysed. However, emerging evidence indicates that, as embryos develop in vitro in culture media, they release cell-free DNA into the media, providing an alternative source of genetic material that can be accessed non-invasively. Spent blastocyst media samples that contain embryo cell-free DNA demonstrate high informativity rates and ploidy concordance when compared with the corresponding trophectoderm, inner cell mass, or whole blastocyst results. However, optimising this non-invasive approach requires several changes to embryo culture protocols, including additional embryo washes to tackle contamination and extending embryo culture time to maximise the amount of cell-free DNA released into the culture media. In this review, we discuss this novel non-invasive approach for aneuploidy detection and embryo prioritisation, as well as the current data and future prospects for utilising cell-free DNA analysis to identify structural rearrangements and single gene disorders. Full article