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Molecular Human Reproduction Jan 2022Sperm DNA damage is considered a predictive factor for the clinical outcomes of patients undergoing ART. Laboratory evidence suggests that zygotes and developing embryos...
Sperm DNA damage is considered a predictive factor for the clinical outcomes of patients undergoing ART. Laboratory evidence suggests that zygotes and developing embryos have adopted specific response and repair mechanisms to repair DNA damage of paternal origin. We have conducted a systematic review in accordance with guidelines from Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to identify and review the maternal mechanisms used to respond and repair sperm DNA damage during early embryonic development, how these mechanisms operate and their potential clinical implications. The literature search was conducted in Ovid MEDLINE and Embase databases until May 2021. Out of 6297 articles initially identified, 36 studies were found to be relevant through cross referencing and were fully extracted. The collective evidence in human and animal models indicate that the early embryo has the capacity to repair DNA damage within sperm by activating maternally driven mechanisms throughout embryonic development. However, this capacity is limited and likely declines with age. The link between age and decreased DNA repair capacity could explain decreased oocyte quality in older women, poor reproductive outcomes in idiopathic cases and patients who present high sperm DNA damage. Ultimately, further understanding mechanisms underlying the maternal repair of sperm DNA damage could lead to the development of targeted therapies to decrease sperm DNA damage, improved oocyte quality to combat incoming DNA insults or lead to development of methodologies to identify individual spermatozoa without DNA damage.
Topics: Aged; Animals; DNA Damage; DNA Repair; Embryonic Development; Female; Humans; Male; Oocytes; Pregnancy; Spermatozoa
PubMed: 34954800
DOI: 10.1093/molehr/gaab071 -
Reviews in Endocrine & Metabolic... Dec 2023Polycystic ovary syndrome (PCOS) is recognized as one of the most prevalent endocrinopathy in women at reproductive age. As affected women tend to have poorer assisted... (Review)
Review
Polycystic ovary syndrome (PCOS) is recognized as one of the most prevalent endocrinopathy in women at reproductive age. As affected women tend to have poorer assisted reproductive technology (ART) outcomes, PCOS has been suggested to endanger oocyte quality and competence development. The aim of this systematic review was to summarize the available evidence on how the follicular fluid (FF) profile of women with PCOS undergoing in vitro fertilization (IVF) treatment differs from the FF of normo-ovulatory women. For that, an electronic search in PubMed and Web of Science databases was conducted (up to December 2021). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses - PRISMA guidelines were followed, and the Newcastle-Ottawa Scale was used to assess the risk of bias in the included studies. Data retrieved from papers included (n=42), revealed that the FF composition of women with PCOS compared to those without PCOS predominantly diverged at the following molecular classes: oxidative stress, inflammatory biomarkers, growth factors and hormones. Among those biomarkers, some were proposed as being closely related to pathophysiological processes, strengthening the hypothesis that low-grade inflammation and oxidative stress play a critical role in the pathogenesis of PCOS. Notwithstanding, it should be noticed that the available data on PCOS FF fingerprints derives from a limited number of studies conducted in a relatively small number of subjects. Furthermore, phenotypic heterogeneity of PCOS hampers wider comparisons and weakens putative conclusions. Therefore, future studies should be focused at comparing well characterized patient subgroups according to phenotypes.
Topics: Female; Humans; Polycystic Ovary Syndrome; Follicular Fluid; Fertilization in Vitro; Oocytes; Biomarkers
PubMed: 37493841
DOI: 10.1007/s11154-023-09819-z -
Human Reproduction Update Apr 2021Delayed parenthood, by both women and men, has become more common in developed countries. The adverse effect of advanced maternal age on embryo aneuploidy and... (Meta-Analysis)
Meta-Analysis
Is there an association between paternal age and aneuploidy? Evidence from young donor oocyte-derived embryos: a systematic review and individual patient data meta-analysis.
BACKGROUND
Delayed parenthood, by both women and men, has become more common in developed countries. The adverse effect of advanced maternal age on embryo aneuploidy and reproductive outcomes is well known. However, whether there is an association between paternal age (PA) and embryonic chromosomal aberrations remains controversial. Oocyte donation (OD) is often utilized to minimize maternal age effects on oocyte and embryo aneuploidy, thus providing an optimal model to assess the effect of PA. Several studies have revealed a higher than expected rate of aneuploidy in embryos derived from young oocyte donors, which warrants examination as to whether this may be attributed to advanced PA (APA).
OBJECTIVE AND RATIONALE
The objective of this systematic review and individual patient data (IPD) meta-analysis is to evaluate existing evidence regarding an association between PA and chromosomal aberrations in an OD model.
SEARCH METHODS
This review was conducted according to PRISMA guidelines for systematic reviews and meta-analyses. Medline, Embase and Cochrane databases were searched from inception through March 2020 using the (MeSH) terms: chromosome aberrations, preimplantation genetic screening and IVF. Original research articles, reporting on the types and/or frequency of chromosomal aberrations in embryos derived from donor oocytes, including data regarding PA, were included. Studies reporting results of IVF cycles using only autologous oocytes were excluded. Quality appraisal of included studies was conducted independently by two reviewers using a modified Newcastle-Ottawa Assessment Scale. A one-stage IPD meta-analysis was performed to evaluate whether an association exists between PA and aneuploidy. Meta-analysis was performed using a generalized linear mixed model to account for clustering of embryos within patients and clustering of patients within studies.
OUTCOMES
The search identified 13 032 references, independently screened by 2 reviewers, yielding 6 studies encompassing a total of 2637 IVF-OD cycles (n = 20 024 embryos). Two 'low' quality studies using FISH to screen 12 chromosomes on Day 3 embryos (n = 649) reported higher total aneuploidy rates and specifically higher rates of trisomy 21, 18 and 13 in men ≥50 years. One 'moderate' and three 'high' quality studies, which used 24-chromosome screening, found no association between PA and aneuploidy in Day 5/6 embryos (n = 12 559). The IPD meta-analysis, which included three 'high' quality studies (n = 10 830 Day 5/6 embryos), found no significant effect of PA on the rate of aneuploidy (odds ratio (OR) 0.97 per decade of age, 95% CI 0.91-1.03), which was robust to sensitivity analyses. There was no association between PA and individual chromosome aneuploidy or segmental aberrations, including for chromosomes X and Y (OR 1.06 per decade of age, 95% CI 0.92-1.21). Monosomy was most frequent for chromosome 16 (217/10802, 2.01%, 95% CI 1.76-2.29%) and trisomy was also most frequent for chromosome 16 (194/10802, 1.80%, 95% CI 1.56-2.06%).
WIDER IMPLICATIONS
We conclude, based on the available evidence, that APA is not associated with higher rates of aneuploidy in embryos derived from OD. These results will help fertility practitioners when providing preconception counselling, particularly to older men who desire to have a child.
Topics: Aged; Aneuploidy; Female; Fertilization in Vitro; Humans; Male; Oocyte Donation; Oocytes; Paternal Age; Pregnancy; Preimplantation Diagnosis
PubMed: 33355342
DOI: 10.1093/humupd/dmaa052 -
JBRA Assisted Reproduction Mar 2023The aim of this study is to analyze the efficacy of the dual trigger (human chorionic gonadotropin (hCG) + GnRH agonists) compared to the conventional trigger (hCG) in... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
The aim of this study is to analyze the efficacy of the dual trigger (human chorionic gonadotropin (hCG) + GnRH agonists) compared to the conventional trigger (hCG) in terms of oocyte retrieval (number and oocyte maturity), fertilization rate or number of embryos with two pronuclei, number of high-quality embryos, number of transferred embryos, number of cryopreserved embryos, implantation rate, positive β-hCG rate, ongoing pregnancy rate, abortion rate, and live birth rate.
METHODS
This search performed in this systematic review included all literature published in the PubMed database of studies on controlled ovarian stimulation with dual trigger compared with conventional trigger. The meta-analysis included clinical trials and prospective cohort studies.
RESULTS
Statistically significant differences between groups (dual trigger vs. hCG trigger) in terms of number of oocytes retrieved and live birth rate favored the dual trigger protocol. No statistically significant differences were found in the other studied variables. A tend favoring the dual trigger protocol was observed in all studied parameters.
CONCLUSIONS
Dual trigger seems to be more effective in GnRH antagonist cycles in terms of embryo and pregnancy outcome.
Topics: Female; Pregnancy; Humans; Sperm Injections, Intracytoplasmic; Prospective Studies; Ovulation Induction; Gonadotropin-Releasing Hormone; Fertilization in Vitro; Oocytes; Chorionic Gonadotropin; Retrospective Studies
PubMed: 36356171
DOI: 10.5935/1518-0557.20220035 -
Journal of Assisted Reproduction and... Oct 2023The biggest cell in the human body, the oocyte, encloses almost the complete machinery to start life. Despite all the research performed to date, defining oocyte quality... (Review)
Review
The biggest cell in the human body, the oocyte, encloses almost the complete machinery to start life. Despite all the research performed to date, defining oocyte quality is still a major goal of reproductive science. It is the consensus that mature oocytes are transcriptionally silent although, during their growth, the cell goes through stages of active transcription and translation, which will endow the oocyte with the competence to undergo nuclear maturation, and the oocyte and embryo to initiate timely translation before the embryonic genome is fully activated (cytoplasmic maturation). A systematic search was conducted across three electronic databases and the literature was critically appraised using the KMET score system. The aim was to identify quantitative differences in transcriptome of human oocytes that may link to patient demographics that could affect oocyte competence. Data was analysed following the principles of thematic analysis. Differences in the transcriptome were identified with respect to age or pathological conditions and affected chromosome mis segregation, perturbations of the nuclear envelope, premature maturation, and alterations in metabolic pathways-amongst others-in human oocytes.
Topics: Humans; Oocytes; Oogenesis; Transcriptome; Cytoplasm; RNA, Messenger
PubMed: 37558907
DOI: 10.1007/s10815-023-02906-9 -
Journal of Assisted Reproduction and... Feb 2024Although significant improvements in assisted reproductive technology (ART) outcomes have been accomplished, a critical question remains: which embryo is most likely to... (Review)
Review
PURPOSE
Although significant improvements in assisted reproductive technology (ART) outcomes have been accomplished, a critical question remains: which embryo is most likely to result in a pregnancy? Embryo selection is currently based on morphological and genetic criteria; however, these criteria do not fully predict good-quality embryos and additional objective criteria are needed. The cumulus cells are critical for oocyte and embryo development. This systematic review assessed biomarkers in cumulus-oocyte complexes and their association with successful IVF outcomes.
METHODS
A comprehensive search was conducted using PubMed, Embase, Scopus, and Web of Science from inception until November 2022. Only English-language publications were included. Inclusion criteria consisted of papers that evaluated genetic biomarkers associated with the cumulus cells (CCs) in humans and the following three outcomes of interest: oocyte quality, embryo quality, and clinical outcomes, including fertilization, implantation, pregnancy, and live birth rates.
RESULTS
The search revealed 446 studies of which 42 met eligibility criteria. Nineteen studies correlated genetic and biochemical biomarkers in CCs with oocyte quality. A positive correlation was reported between oocyte quality and increased mRNA expression in CCs of genes encoding for calcium homeostasis (CAMK1D), glucose metabolism (PFKP), extracellular matrix (HAS2, VCAN), TGF-β family (GDF9, BMP15), and prostaglandin synthesis (PTGS2). Nineteen studies correlated genetic and biochemical biomarkers in CCs with embryo quality. A positive correlation was reported between embryo quality and increased mRNA expression in CCs of genes encoding for extracellular matrix (HAS2), prostaglandin synthesis (PTGS2), steroidogenesis (GREM1), and decreased expression of gene encoding for hormone receptor (AMHR2). Twenty-two studies assessed genetic and biochemical biomarkers in CCs with clinical outcomes. Increased expression of genes encoding for extracellular matrix (VCAN), and TGF-β family (GDF9, BMP15) were positively correlated with pregnancy rate.
CONCLUSION
Genetic biomarkers from cumulus cells were associated with oocyte quality (CAMK1D, PFKP, HAS2, VCAN, GDF-9, BMP-15, PTGS2), embryo quality (GREM1, PTGS2, HAS2), and pregnancy rate (GDF9, BMP15, VCAN). These results might help guide future studies directed at tests of cumulus cells to devise objective criteria to predict IVF outcomes.
Topics: Pregnancy; Female; Humans; Cumulus Cells; Cyclooxygenase 2; Oocytes; Fertilization in Vitro; Reproductive Techniques, Assisted; Genetic Markers; RNA, Messenger; Transforming Growth Factor beta; Prostaglandins
PubMed: 37947940
DOI: 10.1007/s10815-023-02984-9 -
Journal of Assisted Reproduction and... Mar 2023While delayed parenthood is increasing worldwide, the effect of paternal age on in vitro fertilization (IVF) outcomes remains unclear. The egg donation model appears to... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
While delayed parenthood is increasing worldwide, the effect of paternal age on in vitro fertilization (IVF) outcomes remains unclear. The egg donation model appears to be relevant to studying the independent impact of paternal age on clinical outcome, but the available studies are heterogeneous and contradictory. This systematic review and meta-analysis aimed to assess the relationship between paternal age and live birth rate (LBR) in egg donation cycles.
METHODS
A systematic search of the literature was conducted in PubMed, Embase, and the Cochrane Library from inception to June 30, 2021. All studies on egg donation cycles where LBR is reported according to male age were included. Study selection, bias assessment, and data extraction were performed by two independent reviewers according to the Cochrane methods.
RESULTS
Eleven studies involving 10,527 egg donation cycles were finally included. The meta-analysis showed a slight but significant and linear decrease in LBR with increasing paternal age (estimate - 0.0055; 95% CI (- 0.0093; - 0.0016), p = 0.006), with low heterogeneity (I = 25%). No specific threshold was identified. A similar trend toward decreased clinical pregnancy rate with advancing paternal age was found but did not reach statistical significance (p = 0.07).
CONCLUSION
This meta-analysis demonstrates that increasing paternal age is associated with a slight but significant and linear decrease in the live birth rate in egg donation cycles, with no apparent threshold effect. Although this requires further confirmation, this information is important for counseling men who are considering delayed childbearing.
Topics: Pregnancy; Female; Male; Humans; Birth Rate; Paternal Age; Pregnancy Rate; Fertilization in Vitro; Oocytes; Live Birth; Retrospective Studies; Oocyte Donation
PubMed: 36652117
DOI: 10.1007/s10815-023-02714-1 -
International Journal of Molecular... Aug 2022Worldwide, infertility affects between 10 and 15% of reproductive-aged couples. Female infertility represents an increasing health issue, principally in developing... (Review)
Review
Worldwide, infertility affects between 10 and 15% of reproductive-aged couples. Female infertility represents an increasing health issue, principally in developing countries, as the current inclinations of delaying pregnancy beyond 35 years of age significantly decrease fertility rates. Female infertility, commonly imputable to ovulation disorders, can be influenced by several factors, including congenital malformations, hormonal dysfunction, and individual lifestyle choices, such as smoking cigarettes, stress, drug use and physical activity. Moreover, diet-related elements play an important role in the regulation of ovulation. Modern types of diet that encourage a high fat intake exert a particularly negative effect on ovulation, affecting the safety of gametes and the implantation of a healthy embryo. Identifying and understanding the cellular and molecular mechanisms responsible for diet-associated infertility might help clarify the confounding multifaceted elements of infertility and uncover novel, potentially curative treatments. In this view, this systematic revision of literature will summarize the current body of knowledge of the potential effect of high-fat diet (HFD) exposure on oocyte and follicular quality and consequent female reproductive function, with particular reference to molecular mechanisms and pathways. Inflammation, oxidative stress, gene expression and epigenetics represent the main mechanisms associated with mammal folliculogenesis and oogenesis.
Topics: Animals; Diet, High-Fat; Female; Humans; Infertility, Female; Mammals; Oocytes; Oogenesis; Ovulation; Pregnancy
PubMed: 36012154
DOI: 10.3390/ijms23168890 -
Human Reproduction Update Apr 2021IVM was implemented in medically assisted reproduction 25 years ago. IVM does not involve controlled ovarian stimulation (COS) and is mainly indicated in patients with... (Meta-Analysis)
Meta-Analysis
BACKGROUND
IVM was implemented in medically assisted reproduction 25 years ago. IVM does not involve controlled ovarian stimulation (COS) and is mainly indicated in patients with a high risk of ovarian hyperstimulation syndrome, in particular in patients with polycystic ovary syndrome (PCOS); it is also an acknowledged option in fertility protection. However, the in-vitro culture of immature oocytes raises concerns over their developmental potential and the putative impact on children's health. Although an increasing number of studies on obstetric and neonatal outcomes of IVM children and their development have been published in recent years, study designs are difficult to compare, since IVM is used in women with various indications and IVM protocols do not follow the same standards.
OBJECTIVE AND RATIONALE
The aim of this systematic review was to evaluate the current evidence from IVM children of an impact of in-vitro culture of immature oocytes. Primary outcome parameters were birthweight and children's development up to the age of 2 years. We also compared pregnancy pathologies and the outcome of IVM children and COS children in relation to maternal indications, in particular PCOS, and to the type of IVM protocols with or without ovulation trigger as the secondary outcome parameters. IVM is an accepted clinical option for many centres; however, a comprehensive analysis of the available data is needed to establish whether the use of human oocytes that are fully matured in vitro is safe for both children and their mothers.
SEARCH METHODS
Google Scholar and PubMed were used for identifying peer-reviewed original articles and reviews through January 2020. A total of 191 studies were screened and 16 studies were included in the qualitative synthesis. Studies were stratified according to indications, the use of an ovulation trigger and multiplicity.
OUTCOMES
Birthweights of IVM singletons and multiples were comparable to their respective COS controls: birthweights were also similar if the analysis was restricted to mothers with PCOS. IVM children had a comparable birthweight to COS children, irrespective of whether an ovulation trigger was used in IVM cycles or not. The frequency of gestational diabetes (GD) in singleton pregnancies was comparable between IVM and COS, regardless of infertility background. There was also no difference in GD frequency between IVM and COS, if an hCG ovulation trigger in IVM cycles was used or not. Hypertensive disorders in singleton pregnancies of women with PCOS were significantly more frequent after IVM compared to COS, in particular if IVM cycles were performed only with in-vitro matured oocytes. There was no difference in the preterm birth rate of singleton pregnancies between IVM and COS. Preterm birth rates were still similar if only women diagnosed with PCOS were compared and whether an ovulation trigger in IVM was used or not. The malformation rate in IVM children did not differ in COS children versus children after natural conception. At the age of 2 years, IVM singletons showed similar anthropometric and mental development compared to COS children or children from natural conception.
WIDER IMPLICATIONS
The higher incidence of hypertensive disorders in IVM pregnancies needs monitoring during pregnancy. Current data on the development of IVM children are encouraging, although the quality of many studies is limited and long-term data beyond 2 years are scarce. Further studies should be based on generally accepted IVM protocols. Studies on long-term outcomes beyond 2 years are needed to search for potential long-time sequelae of IVM.
Topics: Child, Preschool; Female; Humans; Infant, Newborn; Oocytes; Ovulation; Ovulation Induction; Polycystic Ovary Syndrome; Pregnancy; Premature Birth
PubMed: 33377477
DOI: 10.1093/humupd/dmaa056 -
International Journal of Molecular... Apr 2022Gamete membrane fusion is a critical cellular event in sexual reproduction. In addition, the generation of knockout models has provided a powerful tool for testing the... (Review)
Review
Gamete membrane fusion is a critical cellular event in sexual reproduction. In addition, the generation of knockout models has provided a powerful tool for testing the functional relevance of proteins thought to be involved in mammalian fertilization, suggesting IZUMO1 and TMEM95 (transmembrane protein 95) as essential proteins. However, the molecular mechanisms underlying the process remain largely unknown. Therefore, the aim of this study was to summarize the current knowledge about IZUMO1 and TMEM95 during mammalian fertilization. Hence, three distinct databases were consulted-PubMed, Scopus and Web of Science-using single keywords. As a result, a total of 429 articles were identified. Based on both inclusion and exclusion criteria, the final number of articles included in this study was 103. The results showed that IZUMO1 is mostly studied in rodents whereas TMEM95 is studied primarily in bovines. Despite the research, the topological localization of IZUMO1 remains controversial. IZUMO1 may be involved in organizing or stabilizing a multiprotein complex essential for the membrane fusion in which TMEM95 could act as a fusogen due to its possible interaction with IZUMO1. Overall, the expression of these two proteins is not sufficient for sperm-oocyte fusion; therefore, other molecules must be involved in the membrane fusion process.
Topics: Animals; Cattle; Fertilization; Immunoglobulins; Male; Mammals; Membrane Proteins; Sperm-Ovum Interactions; Spermatozoa
PubMed: 35409288
DOI: 10.3390/ijms23073929