Impaired Oocyte Quality Research Articles

Advanced maternal age affects their frozen-thawed embryo susceptibility to high oxygen environment

Preimplantation embryos can experience stress from laboratory interventions and a sub-optimal culture environment. Though research has demonstrated advanced maternal age impairs oocyte quality, the response of embryos derived from such oocytes to vitrification-thawing and culture in a high oxygen (O2) environment in the assisted reproductive technology laboratory is unknown. Therefore, in this study, embryos produced by in vitro fertilization (IVF) using oocytes from two- and eight-month-old Swiss albino mice were vitrified and thawed during their 6–8 cell stage. and cultured at low oxygen (5%) tension (LOT) and high oxygen (20%) tension (HOT). Embryo development, apoptosis, inner cell mass (ICM) outgrowth proliferation ability in vitro and pluripotency were assessed. Embryos from advanced maternal age cultured at HOT showed reduced fertilizing ability (p < 0.05), poor survival post-thawing (p < 0.05), and increased apoptosis (p < 0.01) in comparison to sibling embryos cultured at LOT. Importantly, the extended culture of vitrified-thawed embryos from advanced maternal age led to a significant (p < 0.001) reduction in complete ICM outgrowth formation at HOT in comparison to the LOT environment. The findings of this study suggest that HOT is detrimental to embryos from advanced maternal age, and importantly, vitrified-thawed embryos are more susceptible to stress, which could have negative implications, especially during the peri-implantation developmental period.

Melatonin partially rescues defects induced by tranexamic acid exposure during oocyte maturation in mice.

Tranexamic acid (TXA) is widely used among young women because of its ability to whiten skin and treat menorrhagia. Nevertheless, its potential effects on oocyte maturation and quality have not yet been clearly clarified. Melatonin (MT) is an endogenous hormone released by the pineal gland and believed to protect cells from oxidative stress injury. In the present study, we used an in vitro maturation model to investigate the toxicity of TXA and the protective role of MT in mouse oocytes. Compared with the control group, the TXA-exposed group had significantly lower nuclear maturation (57.72% vs. 94.08%, P < 0.001) and early embryo cleavage rates (38.18% vs. 87.66%, P < 0.001). Further study showed that spindle organization (52.56% vs. 18.77%, P < 0.01) and chromosome alignment (33.23% vs. 16.66%, P < 0.01) were also disrupted after TXA treatment. Mechanistically, we have demonstrated that TXA induced early apoptosis of oocytes (P < 0.001) by raising the level of reactive oxygen species (P < 0.001), which was consistent with an increase in mitochondrial damage (P < 0.01). Fortunately, all these effects except the spindle defect were successfully rescued by an appropriate level of MT. Collectively, our findings indicate that MT could partially reverse TXA-induced oocyte quality deterioration in mice by effectively improving mitochondrial function and reducing oxidative stress-mediated apoptosis.NEW & NOTEWORTHY Tranexamic acid is increasingly used to whiten skin, reverse dermal damages, and treat heavy menstrual bleeding in young women. However, its potential toxicity in mammalian oocytes is still unclear. Our study revealed that tranexamic acid exposure impaired the mouse oocyte quality and subsequent embryo development. Meanwhile, melatonin has been found to exert beneficial effects in reducing tranexamic acid-induced mitochondrial dysfunction and oxidative stress.

Polystyrene nanoplastics induce apoptosis, autophagy, and steroidogenesis disruption in granulosa cells to reduce oocyte quality and fertility by inhibiting the PI3K/AKT pathway in female mice

BackgroundNanoplastics (NPs) are emerging pollutants that pose risks to living organisms. Recent findings have unveiled the reproductive harm caused by polystyrene nanoparticles (PS-NPs) in female animals, yet the intricate mechanism remains incompletely understood. Under this research, we investigated whether sustained exposure to PS-NPs at certain concentrations in vivo can enter oocytes through the zona pellucida or through other routes that affect female reproduction.ResultsWe show that PS-NPs disrupted ovarian functions and decreased oocyte quality, which may be a contributing factor to lower female fertility in mice. RNA sequencing of mouse ovaries illustrated that the PI3K-AKT signaling pathway emerged as the predominant environmental information processing pathway responding to PS-NPs. Western blotting results of ovaries in vivo and cells in vitro showed that PS-NPs deactivated PI3K-AKT signaling pathway by down-regulating the expression of PI3K and reducing AKT phosphorylation at the protein level, PI3K-AKT signaling pathway which was accompanied by the activation of autophagy and apoptosis and the disruption of steroidogenesis in granulosa cells. Since PS-NPs penetrate granulosa cells but not oocytes, we examined whether PS-NPs indirectly affect oocyte quality through granulosa cells using a granulosa cell–oocyte coculture system. Preincubation of granulosa cells with PS-NPs causes granulosa cell dysfunction, resulting in a decrease in the quality of the cocultured oocytes that can be reversed by the addition of 17β-estradiol.ConclusionsThis study provides findings on how PS-NPs impact ovarian function and include transcriptome sequencing analysis of ovarian tissue. The study demonstrates that PS-NPs impair oocyte quality by altering the functioning of ovarian granulosa cells. Therefore, it is necessary to focus on the research on the effects of PS-NPs on female reproduction and the related methods that may mitigate their toxicity.

Improved low-invasive mRNA electroporation method into immature mouse oocytes visualizes protein dynamics during development†.

One of the major causes of oocyte quality deterioration, chromosome segregation abnormalities manifest mainly during meiosis I, which occurs before and during ovulation. However, currently, there is a technical limitation in the introduction of mRNA into premature oocytes without impairing embryonic developmental ability. In this study, we established a low-invasive electroporation (EP) method to introduce mRNA into pre-ovulatory, germinal vesicle (GV) mouse oocytes in an easier manner than the traditional microinjection method. The EP method with an optimized impedance value resulted in the efficient introduction of mRNAs encoding enhanced green fluorescent protein (EGFP) into the GV oocytes surrounded by cumulus cells at a survival rate of 95.0%. Furthermore, the introduction of histone H2B-EGFP mRNA into the GV oocytes labeled most of the oocytes without affecting the blastocyst development rate, indicating the feasibility of the visualization of oocyte chromosomal dynamics that enable us to assay chromosomal integrity in oocyte maturation and cell count in embryonic development. The establishment of this EP method offers extensive assays to select pre-implantation embryos and enables the surveying of essential factors for mammalian oocyte quality determination.

Bisphenol M inhibits mouse oocyte maturation in vitro by disrupting cytoskeleton architecture and cell cycle processes

Bisphenol M (BPM), an alternative to bisphenol A (BPA), is commonly utilized in various industrial applications. However, BPM does not represent a safe substitute for BPA due to its detrimental effects on living beings. This research aimed to assess the influence of BPM exposure on the in vitro maturation of mouse oocytes. The findings revealed that BPM exposure had a notable impact on the germinal vesicle breakdown (GVBD) rate and polar body extrusion (PBE) rate throughout the meiotic progression of mouse oocytes, ultimately resulting in meiotic arrest. Investigations demonstrated that oocytes exposure to BPM led to continued activation of spindle assembly checkpoint. Further studies revealed that securin and cyclin B1 could not be degraded in BPM-exposed oocytes, and meiosis could not realize the transition from the MI to the AI stage. Mechanistically, BPM exposure resulted in abnormal spindle assembly and disrupted chromosome alignment of oocytes. Additionally, abnormal positioning of microtubule organizing center-associated proteins implied that MTOC may be dysfunctional. Furthermore, an elevation in the acetylation level of α-tubulin in oocytes was observed after BPM treatment, leading to decreased microtubule stability. In addition to its impact on microtubules, BPM exposure led to a reduction in the expression of the actin, signifying the disruption of actin assembly. Further research indicated a heightened incidence of DNA damage in oocytes following BPM exposure. Besides, BPM exposure induced alterations in histone modifications. The outcomes of this experiment demonstrate that BPM exposure impairs oocyte quality and inhibits meiotic maturation of mouse oocytes.

Glucose metabolism disorder related to follicular fluid exosomal miR-122-5p in cumulus cells of endometriosis patients.

Elevated expression of miR-122-5p in exosomes in the follicular fluid of patients with endometriosis impairs glucose metabolism in cumulus cells and may further impair oocyte quality. Endometriosis (EMs) affects fertility in women of childbearing age in many ways. The underlying mechanisms, including the decrease in oocyte quality, require further investigation. Exosomes, small vesicles responsible for intercellular information exchange, have been found to be involved in many biological events, including follicle development and oocyte meiosis recovery. From the perspective of follicular fluid exosomes, this study aimed to elucidate the mechanisms involved in EMs-related oocyte quality decline. Follicular fluid was collected from three groups of women: the untreated EMs group (EMs_UT), the satisfactorily treated EMs group (EMs_ST), and the control group (Ctrl). Mouse cumulus-oocyte complexes (COCs) were co-cultured with exosomes extracted from follicular fluid during in vitro maturation. Oocyte quality and cumulus cell function were assessed. High-throughput sequencing of miRNA in exosomes was conducted. The function of differentially expressed miRNAs was studied by using SVOG human ovarian granulosa cells transfected with an miRNA mimic and inhibitor. It was found that the follicular fluid exosomes from patients with untreated EMs reduced both the rate of maturation and the quality of mouse oocytes. Overexpression of miR-122-5p in untreated EMs inhibited the translation of key aldolase enzymes related to glucose metabolism and partly impaired glucose metabolism in the cumulus cells of patients with endometriosis. miR-122-5p was also observed to reduce proliferation and increase apoptosis after cell transfection with an miR-122-5p mimic and inhibitor. Further experiments are needed to determine whether there are additional small molecules in the follicular fluid of patients with endometriosis that could be involved in damaging oocyte quality and to identify where harmful substances in follicular fluid exosomes are loaded.

O-217 Evaluating the impact of obesity on oocyte quality, using 2 main factors in cumulus cells (CC) and follicular fluid (FF) which reflect oocyte quality

Abstract Study question How obesity impacts oocyte quality through analysis of mtDNA expression in CC and levels of proteins BMP-15 and HSPG2 in FF? Summary answer There is correlation between increased BMI and lower levels of BMP15 and a decreased expression of mtDNA that reflect decreased oocyte quality in overweight women. What is known already Obesity impacts female health and impairs fertility. There is limited evidence suggesting that obesity impairs oocyte quality. BMP-15 (Bone morphogenetic protein 15) is a protein synthesized by oocyte, is a factor predicting quality of the oocyte and female fertility. Heparan sulfate proteoglycan 2 (HSPG2) is a protein secreted from granulosa cells and there are limited studies regarding the function of HSPG2 in reproduction including oocyte quality. BMP-15 and HSPG2 secreted to FF. Oocyte quality was demonstrated to be influenced by mtDNA (mitochondrial DNA) content in CC. Study design, size, duration Prospective observational cohort study performed between February 2022 until June 2022 in a single university-affiliated hospital. Total of 50 patients were enrolled. Participants/materials, setting, methods Women who underwent IVF or ICSI cycles were included. Exclusion criteria were patients older than 40 years, fertility preservation, unbalanced endocrine disorders and less than 4 follicles at the time of OPU (oocyte pick-up). Follicular fluid and cumulus cells were collected following OPU. mtDNA was assessed by quantitative real-time PCR. BMP-15 and HSPG2 were measured with ELISA method quantitatively. Lipid profile, hormonal profile and C-reactive protein were evaluated in blood and follicular fluid samples. Main results and the role of chance Patients were divided based on BMI, 28 patients with BMI &amp;lt; 25 (Group 1) and 22 with BMI &amp;gt; 25 (Group 2). A significant increase in BMP-15 in FF (38.8 ± 32.5 vs. 14.3 ± 10.8 ng/ml; p = 0.001) and mitochondrial DNA in CC (1.10 ± 0.3 vs. 0.87 ± 0.18 Fold change expression; p = 0.016) were found in group 1. Significantly higher CRP in blood (7.1 ± 5.4 vs. 3.4 ± 4.3; p = 0.015) and FF (5.2 ± 3.8 vs. 1.5 ± 1.6; p = 0.002) and LDL level in blood (91 ± 27 vs. 71 ± 22; p = 0.008) in group 2. HDL levels were significantly higher in group 1 in the blood (50 ± 12 vs. 62 ± 18; p = 0.015) and FF (20.9 ± 7.2 vs. 34 ± 26; p = 0.05). The fresh clinical pregnancy rate demonstrated a trend toward better results in group 1 (47.8% vs. 28.6%: p = 0.31), as well as in FET (69.2% vs. 53.8; P = 0.69). Limitations, reasons for caution Research included relatively small number of participants. We can’t report our cumulative pregnancy rate since not all frozen embryos were transferred yet. Wider implications of the findings Obesity is an increasing worldwide problem and impairs fertility outcome. Our study demonstrates decreased oocyte quality in the group of overweight women through 2 important markers BMP-15 and mtDNA. We recommend our patients to lose weight and improve their lifestyle in order to overcome those impaired quality markers. Trial registration number Not applicable

P-684 Anti-müllerian hormone predictive value for cumulative pregnancy rate in non-infertile women following four intrauterine insemination with donor sperm

Abstract Study question Are anti-Müllerian hormone (AMH) levels predictive of cumulative pregnancy rate in non-infertile women undergoing intrauterine insemination with donor sperm (ds-IUI)? Summary answer AMH has limited predictive value for clinical pregnancy after 4 cycles of ds-IUI in non-infertile women. Decreased AMH concentration does not necessarily reduce pregnancy rates. What is known already Physiologically, pregnancy rates decline due to oocyte quality deterioration upon advancing maternal age. AMH is a widely-used marker of ovarian reserve and follicular response but not an infertility test, despite being sometimes referred to as such. This misconception can lead to unnecessary complex ART treatments only based on low AMH. Indeed, the predictive value of AMH for natural conception and IUI remains uncertain and highly controversial in the literature. Study design, size, duration This multicenter prospective observational study evaluated the correlation between AMH levels and pregnancy rates in 182 non-infertile women undergoing ds-IUI. Participants were recruited from June 2020 to December 2022 from three centers: Hospital del Mar in Barcelona (Spain), Fertty Clinic in Barcelona (Spain) and Clinica de la Mujer in Viña del Mar (Chile). Participants/materials, setting, methods The study included women aged 25-39 years, normal BMI, regular periods, and without ovarian pathology or endometriosis, who were undergoing ds-IUI for severe oligoasthenoteratozoospermia, female partner, or single status. Baseline AMH and antral follicle count (AFC) by TVUS was registered. Reproductive outcomes were compared between women with AMH &amp;gt;1.1 and AMH ≤1.1 ng/mL. The main outcome was the cumulative clinical pregnancy rate after up to 4 ds-IUIs in a 3-year frame. Main results and the role of chance Kaplan Meier’s analysis did not show cumulative pregnancy rate superiority in women with AMH &amp;gt;1.1 ng/mL vs &amp;lt; 1.1 ng/mL (log rank Mentel Cox 1,502; p-value 0.46; ROC curve analysis predictor for clinical pregnancy, AUC=0.586). AMH and AFC were found to be significantly correlated (Pearson’s coefficient r = 0.632, p-value &amp;lt;0.001). Additionally, women who achieved pregnancy were found to be significantly younger (p-value &amp;lt;0.05) versus women who did not. However, no differences in AMH levels were found between them (p-value 0.33). Limitations, reasons for caution Limitations of the study include interpretation of results in extreme concentrations of AMH, potential impact of polycystic ovary syndrome (PCOS) in women with high AMH values, lower representation of patients with low AMH levels, and variability in ovulation induction regimens prior to ds-IUI (exposure to different rFSH dosages). Wider implications of the findings AMH is not a reliable predictor for pregnancy in ds-IUI. Even women with extremely low AMH levels can achieve successful outcomes, which are associated with age. The results of this multicenter study support that low AMH should not be used as an exclusion criterion for non-infertile women seeking ds-IUI. Trial registration number IRB Protocol ID 2020/9445

The role of declining ataxia-telangiectasia-mutated (ATM) function in oocyte aging

Despite the advances in the understanding of reproductive physiology, the mechanisms underlying ovarian aging are still not deciphered. Recent research found an association between impaired ATM-mediated DNA double-strand break (DSB) repair mechanisms and oocyte aging. However, direct evidence connecting ATM-mediated pathway function decline and impaired oocyte quality is lacking. The objective of this study was to determine the role of ATM-mediated DNA DSB repair in the maintenance of oocyte quality in a mouse oocyte knockdown model. Gene interference, in vitro culture, parthenogenesis coupled with genotoxicity assay approaches, as well as molecular cytogenetic analyses based upon next-generation sequencing, were used to test the hypothesis that intact ATM function is critical in the maintenance of oocyte quality. We found that ATM knockdown impaired oocyte quality, resulting in poor embryo development. ATM knockdown significantly lowered or blocked the progression of meiosis in vitro, as well as retarding and reducing embryo cleavage after parthenogenesis. After ATM knockdown, all embryos were of poor quality, and none reached the blastocyst stage. ATM knockdown was also associated with an increased aneuploidy rate compared to controls. Finally, ATM knockdown increased the sensitivity of the oocytes to a genotoxic active metabolite of cyclophosphamide, with increased formation of DNA DSBs, reduced survival, and earlier apoptotic death compared to controls. These findings suggest a key role for ATM in maintaining oocyte quality and resistance to genotoxic stress, and that the previously observed age-induced decline in oocyte ATM function may be a prime factor contributing to oocyte aging.

Surfeit locus protein 4 modulates endoplasmic reticulum function and maintains oocyte quality

ABSTRACT Surfeit locus protein 4 is a cargo receptor mediating cargo transport from the endoplasmic reticulum lumen to the Golgi apparatus. Loss of Surf4 gene led to embryonic lethality in mice. However, the role of Surf4 during oocyte development remains unknown. In this study, we generated the mouse model with oocyte-specific knockout of Surf4 gene. We found that adult mice with deletion of Surf4 showed normal folliculogenesis, ovulation and fertility. However, loss of Surf4 slightly impaired oocyte quality, thus led to partial oocyte meiotic arrest and reduced ratio of blastocyst formation. Consistent with this, the distribution of endoplasmic reticulum was disturbed in Surf4-deficient oocytes in mice. These results demonstrated that although Surf4 is dispensable for female mouse fertility, Surf4 modulates endoplasmic reticulum arrangement and participates in regulation of developmental competence of oocytes.

Enhanced branched-chain amino acid metabolism improves age-related reproduction in C. elegans.

Reproductive ageing is one of the earliest human ageing phenotypes, and mitochondrial dysfunction has been linked to oocyte quality decline; however, it is not known which mitochondrial metabolic processes are critical for oocyte quality maintenance with age. To understand how mitochondrial processes contribute to Caenorhabditis elegans oocyte quality, we characterized the mitochondrial proteomes of young and aged wild-type and long-reproductive daf-2 mutants. Here we show that the mitochondrial proteomic profiles of young wild-type and daf-2 worms are similar and share upregulation of branched-chain amino acid (BCAA) metabolism pathway enzymes. Reduction of the BCAA catabolism enzyme BCAT-1 shortens reproduction, elevates mitochondrial reactive oxygen species levels, and shifts mitochondrial localization. Moreover, bcat-1 knockdown decreases oocyte quality in daf-2 worms and reduces reproductive capability, indicating the role of this pathway in the maintenance of oocyte quality with age. Notably, oocyte quality deterioration can be delayed, and reproduction can be extended in wild-type animals both by bcat-1 overexpression and by supplementing with vitamin B1, a cofactor needed for BCAA metabolism.

Mitochondrial replacement techniques for treating infertility

Mitochondrial replacement techniques (MRTs) usually aim to prevent the genetic transmission of maternally inherited mitochondrial diseases. Until now, only the UK and Australia have implemented specific legal regulations of MRTs....

Reactive oxygen species signalling in the deterioration of quality of mammalian oocytes cultured in vitro: Protective effect of antioxidants

The in vitro fertilization (IVF) is the first choice of infertile couples worldwide to plan for conception. Besides having a significant advancement in IVF procedure, the success rate is still poor. Although several approaches have been tested to improve IVF protocol, minor changes in culture conditions, physical factors and/or drug treatment generate reactive oxygen species (ROS) in oocytes. Due to large size and huge number of mitochondria, oocyte is more susceptible towards ROS-mediated signalling under in vitro culture conditions. Elevation of ROS levels destabilize maturation promoting factor (MPF) that results in meiotic exit from diplotene as well as metaphase-II (M-II) arrest in vitro. Once meiotic exit occurs, these oocytes get further arrested at metaphase-I (M-I) stage or metaphase-III (M-III)-like stage under in vitro culture conditions. The M-I as well as M-III arrested oocytes are not fit for fertilization and limits IVF outcome. Further, the generation of excess levels of ROS cause oxidative stress (OS) that initiate downstream signalling to initiate various death pathways such as apoptosis, autophagy, necroptosis and deteriorates oocyte quality under in vitro culture conditions. The increase of cellular enzymatic antioxidants and/or supplementation of exogenous antioxidants in culture medium protect ROS-induced deterioration of oocyte quality in vitro. Although a growing body of evidence suggests the ROS and OS-mediated deterioration of oocyte quality in vitro, their downstream signalling and related mechanisms remain poorly understood. Hence, this review article summarizes the existing evidences concerning ROS and OS-mediated downstream signalling during deterioration of oocyte quality in vitro. The use of various antioxidants against ROS and OS-mediated impairment of oocyte quality in vitro has also been explored in order to increase the success rate of IVF during assisted reproductive health management.

Dysregulation of ferroptosis-related genes in granulosa cells associates with impaired oocyte quality in polycystic ovary syndrome.

Poor oocyte quality remains one of the major challenges for polycystic ovary syndrome (PCOS) patients during in vitro fertilization (IVF) treatment. Granulosa cells (GCs) in PCOS display altered functions and could cause an unfavorable microenvironment for oocyte growth and maturation. Ferroptosis is a new form of programmed cell death, but its role in PCOS has been largely unclarified. Ferroptosis-related differentially expressed genes (DEGs) of GCs in women with PCOS were identified by bioinformatic analyses of GSE155489 and GSE168404 datasets. Functional enrichment analyses were conducted using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Core ferroptosis-related genes were further screened by random forest, and evaluated for diagnostic value by receiver operating characteristic curve analyses. Gene expression was validated by real-time quantitative polymerase chain reaction of collected GC samples, and analyzed for association with oocyte quality. In addition, gene regulatory network was constructed based on predicted RNA interactions and transcription factors, while potential therapeutic compounds were screened through molecular docking with crystallographic protein structures. A total of 14 ferroptosis-related DEGs were identified. These DEGs were mainly enriched in reactive oxygen species metabolic process, mitochondrial outer membrane, antioxidant activity as well as ferroptosis and adipocytokine signaling pathways. Eight core ferroptosis-related genes (ATF3, BNIP3, DDIT4, LPIN1, NOS2, NQO1, SLC2A1 and SLC2A6) were further selected in random forest model, which showed high diagnostic performance for PCOS. Seven of them were validated in GC samples, and five were found to be significantly and positively correlated with one or more oocyte quality parameters in PCOS patients, including oocyte retrieval rate, mature oocyte rate, normal fertilization rate, and good-quality embryo rate. Gene regulatory network revealed JUN and HMGA1 as two important transcription factors, while dicoumarol and flavin adenine dinucleotide were predicted as small molecules with therapeutic potential. This is the first comprehensive report to study the differential expression of ferroptosis-related genes in GCs of PCOS and their clinical relevance with oocyte quality. Our findings could provide novel insights on the potential role of GC ferroptosis in PCOS pathogenesis, diagnosis, and targeted treatment.

What is the impact of endometriosis and the AFS stage on cumulative pregnancy rates in IVF programs?

BackgroundEndometriosis is commonly observed in infertile women and can be staged with regard to severity [e.g. according to the American Fertility Society (AFS) classification]. This condition can cause infertility through impaired oocyte quality, fertilization disorders, tubal lesions, adhesions, deep infiltration, and adenomyosis. Although women with endometriosis often turn to in vitro fertilization (IVF) programs, the literature data on IVF outcomes are sometimes contradictory (i.e. the same as in other etiologies of infertility, or worse). The objective of the present study was to assess and compare pregnancy rates in women with and without endometriosis and according to the endometriosis stage.MethodsWe retrospectively studied clinical and ongoing pregnancy rates in IVF and the cumulative pregnancy rates after frozen/thawed embryo transfers, in women without endometriosis (group A) or with endometriosis (group B). We further compared groups in which endometriosis was staged according to the revised AFS classification: stage 1/2 (group C), stage 3/4 (group D, without endometrioma), and endometrioma alone (group E).ResultsWe documented 430 cycles in group A and 460 in group B (including 56 in group C, 88 in group D and 316 in group E). After fresh or frozen/thawed embryo transfers, the differences in ongoing pregnancy rates between groups A and B were not significant. However the cumulative rates per couple were significantly lower (p < 0.05) in group D.ConclusionsWe recommend IVF for women with endometriosis because the pregnancy rates are similar to those observed for women with other types of infertility. This approach is in line with the international guidelines issued by assisted reproductive technology societies. These results again raise the question of whether surgical resection of deep infiltrating endometriosis (stage 3/4) should be recommended before admission to an IVF program.Trial registration This study was approved by an institutional review board (CPP Ouest VI, Brest, France): reference: B2020CE.43

Apigenin delays postovulatory oocyte aging by reducing oxidative stress through SIRT1 upregulation

After ovulation, senescent oocytes inevitably experience reduced quality and defects in embryonic development. Apigenin (API) is a flavonoid with a wide range of pharmacological effects. Therefore, this study examined the protective effects of API on the quality of porcine oocytes during in-vitro ageing and the underlying mechanisms. The results showed that API treatment could reduce the activation rate after aging for 48 h. In addition, API significantly reduced reactive oxygen species, abnormal distribution of mitochondria, early apoptosis in ageing oocytes, increased glutathione, and mitochondrial adenosine triphosphate levels in ageing oocytes. Importantly, API increased the embryonic development rate in aged oocytes. We also examined molecular changes, finding decreased sirtuin 1 expression in in-vitro postovulatory oocytes, but API reversed this effect. Our results suggest that API attenuates the deterioration of oocyte quality during in-vitro ageing, possibly by reducing oxidative stress through the upregulation of sirtuin 1.

Aberrantly High FBXO31 Impairs Oocyte Quality in Premature Ovarian Insufficiency.

Premature ovarian insufficiency (POI), which is defined as loss of ovarian function that occurs before the age of 40, causes menstrual disturbances, infertility, and diverse health problems in females. Despite the limited understanding of the molecular basis underlying POI pathology, we had previously demonstrated that the cooperation of miR-106a and FBXO31 plays a pivotal role in diminished ovarian reserve (DOR), with FBXO31 serving as a putative target of miR-106a. In this study, we found that FBXO31 is aberrantly expressed in granulosa cells of POI patients, leading to accumulated reactive oxygen species (ROS) and cell apoptosis via the p53/ROS pathway. Furthermore, our results demonstrated that high levels of FBXO31 in mouse ovaries impair oocyte quality. Our study revealed that FBXO31 may serve as a novel indicator and play a significant role in the etiology of POI.

Free Androgen Index Might Not Be a Perfect Predictor of Infertility Outcomes in Patients with Polycystic Ovary Syndrome Undergoing Frozen Embryo Transfer:A Retrospective Cohort Study.

It is well known that androgen excess impairs oocyte quality, endometrial receptivity and even embryo invasion to some extent. Free androgen index (FAI) is strongly recommended to evaluate active androgen. Previous studies have showed conflicting conclusions on the effect of hyperandrogenism on the pregnancy outcomes in patients with polycystic ovary syndrome (PCOS). This study aims to analyze the influence of hyperandrogenemia based on FAI on frozen embryo transfer (FET) outcomes in patients with PCOS. Patients diagnosed with PCOS who underwent their first FET between January 2017 and April 2022 were stratified into two cohorts using FAI, a highly recommended parameter: PCOS with hyperandrogenemia (n=73) and PCOS without hyperandrogenemia (n=255). Basic and infertility characteristics were analyzed using Student's t-test or chi-square (χ2) statistics. Logistic regression analysis was performed to verify whether FAI was helpful in predicting pregnancy outcomes in women with PCOS. Body mass index (BMI), total gonadotropin (Gn), basal serum follicle-stimulating hormone (bFSH), basal serum testosterone (bT), sex hormone binding globulin (SHBG), and FAI were significantly different between the two groups. (P=0.005, P<0.001, P<0.001, P<0.001, and P<0.001, respectively). However, clinical pregnancies, abortions, and live births did not differ significantly. Further regression analyses showed that FAI was not related to clinical pregnancy, abortion, or live birth rates (adjusted odds ratio (OR)=0.978, 95% confidence interval (CI)=0.911-1.050, P=0.539; adjusted OR=1.033, 95% CI=0.914-1.168, P=0.604; and adjusted OR=0.976, 95% CI=0.911-1.047, P=0.499, respectively). FAI was not associated with pregnancy outcomes in patients with PCOS; that is, it did not reflect any negative effects of hyperandrogenemia on pregnancy outcomes in patients with PCOS and was not an informative clinical parameter. Therefore, more attention should be paid to the factors that influence the accuracy of FAI in reflecting androgen levels in vivo, and further discussion is needed.

Down-regulation of the FTO gene in follicular fluid of infertile women with ovarian endometriosis

Objective To evaluate FTO concentrations in follicular fluid (FF) of women with ovarian endometriosis (OE) and controls women without OE undergoing in vitro fertilization-embryo transfer (IVF-ET). Methods FTO concentrations in FF were measured in 74 patients (37 in the control group and 37 in the OE group) by ELISA. We measured the expression of FTO in GCs of 40 patients (19 in the control group and 21 in the OE group) by RT-qPCR. The level of m6A in GCs was measured in 20 patients (10 in the control group and 10 in the OE group) by colorimetry. Results Compared with the control group, FTO concentrations in FF (6.92 ± 0.44 vs. 5.67 ± 0.40 ng/ml) (p <.05) and FTO mRNA level in GCs of OE group were decreased significantly (p <.05), and the level of m6A was increased (0.21 ± 0.01 vs. 0.17 ± 0.03 ng) (p >.05). Conclusions The FTO concentrations in FF of infertility women with OE are decreased, which may be related to the impaired oocyte quality in endometriosis patients.

Clinical outcome of different embryo transfer strategies after late rescue ICSI procedure: a 10-year total fertilisation failure cohort study

BackgroundLate rescue intracytoplasmic sperm injection (r-ICSI) has not been widely accepted as an alternative solution for unexpected total fertilisation failure (TFF) after in vitro fertilisation (IVF), due to the time-dependent in vitro deterioration of oocyte quality and endometrial growth not being synchronised with embryo development. This study aimed to evaluate the safety profile and effectiveness of freeze-all blastocyst transfer in combination with late r-ICSI.MethodsThis was a retrospective cohort study carried out at the Reproductive Centre of Peking University Third Hospital, Beijing, China. All participants received treatment between 2009 and 2019. 2,270 patients in the aggregate encountered unexpected TFF during 149,054 cycles of IVF and adopted a late r-ICSI procedure. Among these patients, 263 women did not have cleavage-stage embryos available for evaluation. The remaining patients were grouped according to different embryo transfer (ET) strategies (926 women in Group 1 underwent fresh ET, 365 women in Group 2 underwent freeze-all ET, 716 women in Group 3 experienced blastulation failure). Patients received different ET strategies after r-ICSI, with the main outcome measures included live birth rate (LBR), cumulative live birth rate (cLBR), and conservative cLBR.ResultsTFF occurred in 7.4% of all IVF cycles. Group 1 tended to be older at oocyte retrieval, with more infertile years, higher follicle-stimulating hormone (FSH) levels, higher gonadotropin consumption, and fewer oocytes retrieved. Group 2 exhibited considerably better LBRs following the first ET cycle (37.53% vs. 4.64%) and cLBRs (52.60% vs. 8.21%). After adjustment for covariates using binary logistic regression analyses, Group 2 still showed better obstetric performance in LBRs [OR:11.77, 95% CI (8.42–16.45)], cLBRs (OR:11.29, 95% CI (7.84–16.27)], and conservative cLBRs (OR:2.55, 95% CI (1.83–3.55)]. Additionally, the two groups showed similar miscarriage rates, whilst no new-borns with malformations or congenital diseases were reported.ConclusionsFreeze-all blastocyst stage ET serves as an optimal strategy to support late r-ICSI. However, for women with limited oocytes available for r-ICSI use, weighing the benefits against the costs of the procedure might be prudent before implementing in vitro blastulation.