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Background: Hematopoietic stem cell transplantation (HSCT) is an approach that has significantly improved the prognosis and survival of hematological patients. However, ovarian dysfunction and infertility following HSCT have gained increasing attention. Live births have been reported following ovarian tissue cryopreservation prior to HSCT and subsequent retransplantation of these tissues. Still, the feasibility of ovarian tissue cryopreservation (OTC) following graft failure (GF) of HSCT remains unknown. In this study, we report the first case of OTC following a GF of allogenic HSCT (allo-HSCT), as well as the cryopreservation of four MII oocytes via in vitro maturation with informed consent. Despite the lack of clinical outcomes after cryopreserved ovarian tissue retransplantation, we documented an interesting case in a woman after GF of allo-HSCT exhibiting functional ovaries and emphasized a clinical dilemma: whether OTC should be offered to women suffering from GF of HSCT. Case presentation: A 22-year-old woman with severe aplastic anemia who had suffered GF of allo-HSCT from her sibling brother [HLA allele match (7/10)] with a reduced dose conditioning regimen including fludarabine, cyclophosphamide, and antithymocyte globulin came to our reproductive center for fertility preservation, as she was about to receive the second allo-HSCT. We evaluated the ovarian reserve of this patient. Hormone assessments showed an anti-Müllerian hormone level of 3.921 ng/mL, a follicle-stimulating hormone level of 5.88 IU/L, a luteinizing hormone level of 10.79 IU/L, and an estradiol level of 33.34 pg/mL. Antral follicle counts accessed transvaginally showed 12-15 follicles. All assessments indicated a well-protected ovarian reserve. Due to the urgency of the second allo-HSCT, the patient decided to undergo ovarian cryopreservation. Laparoscopic surgery proceeded. Ovarian tissues were successfully cryopreserved using vitrification technology, and histologic evaluation demonstrated a follicle density of 20 per 2 × 2 mm2 biopsy with good viability. Four MII oocytes were obtained via in vitro maturation technology and cryopreserved. After the second HSCT, the patient relieved from aplastic anemia but suffered iatrogenic premature ovarian failure as predicted. Conclusion: OTC is applicable to fertility preservation in those undergoing GF of HSCT with benign hematological disorders and especially those who are about to receive the second HSCT.

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OBJECTIVE: To compare oocyte maturation rates and pregnancy outcomes in women with polycystic ovary syndrome (PCOS) undergoing biphasic in vitro maturation (capacitation [CAPA]-IVM) with versus without follicle-stimulating hormone (FSH) priming. DESIGN: Randomized, controlled, assessor-blinded trial SUBJECTS: Women aged 18-37 years with PCOS and an indication for CAPA-IVM. INTERVENTION: Participants were randomized (1:1) to undergo CAPA-IVM with or without FSH priming. The FSH priming group had two days of FSH injections before oocyte pick-up; no FSH was given in the non-FSH group. After CAPA-IVM, day-5 embryos were vitrified for transfer in a subsequent cycle. MAIN OUTCOME MEASURE(S): The primary endpoint was number of matured oocytes. Secondary outcomes included rates of live birth, implantation, clinical pregnancy, ongoing pregnancy, pregnancy complications, obstetric and perinatal complications, and neonatal complications. RESULTS: The number [interquartile range] of matured oocytes did not differ significantly in the non-FSH versus FSH group (13 [9-18] vs. 14 [7-8]; absolute difference -1 [95% confidence interval (CI) -5, 4]); other oocyte and embryology outcomes did not differ between groups. Rates of ongoing pregnancy and live birth were both 38.3% in the non-FSH group and both 31.7% in the FSH group (risk ratio for both outcomes: 1.21, 95% CI 0.74-1.98). Maternal complications were infrequent and occurred at a similar rate in the two groups; there were no preterm deliveries before 32 weeks' gestation. CONCLUSION: These findings open the possibility of a new, hormone-free approach to infertility treatment of women with PCOS.

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Zinc oxide nanoparticles (ZnO-NPs) have garnered significant attention in biological applications due to their known antioxidant properties. However, their potential impact on assisted reproduction techniques remains largely unexplored, particularly in the context of oocyte quality maintenance within in vitro culture systems, where free radicals can exert detrimental effects. This study investigated the effects of incorporating ZnO-NPs to in vitro maturation (IVM) media on the developmental, cryosurvival, and metabolic profiles of bovine embryos. Three concentrations of ZnO-NPs (0, 1.0, and 1.5 µg/mL) were evaluated. We observed, for the first time, that the inclusion of ZnO-NPs at a concentration of 1.0 µg/mL led to a significant increase in the number of embryonic cells (p < 0.05) accompanied by a reduction in reactive oxygen species production (p < 0.05). Notably, ZnO-NPs did not alter embryonic development, cryosurvival rates, or mitochondrial viability. These findings suggested that ZnO-NPs has antioxidant properties and are compatible with bovine oocytes. Consequently, they may serve as promising supplements to the IVM media, potentially enhancing the efficiency of assisted reproduction techniques.

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Objective: To review the outcomes of in vitro maturation (IVM) and in vitro fertilization (IVF) in women with empty follicle syndrome (EFS). The study evaluated the genetic underpinnings of EFS by analyzing mutations. Materials and Methods: This retrospective case series involving 17 women with EFS over at least 2 IVF cycles was conducted. The study also employed whole-exome sequencing to analyze the genetic mutations. The treatment approaches included letrozole-primed IVM, follicle-stimulating hormone (FSH)-human chorionic gonadotrophin (hCG)-primed IVM, and conventional IVF. Results: The average female age was 31.5±4.6 years, and the duration of infertility was 7.3±3.5 years. Four patients underwent IVF. IVM oocyte collections yielded oocytes in 12 of 13 subjects. Of these, 75% (9/12) yielded MII oocytes after 48 h of IVM media incubation. Six subjects had fertilized embryos, resulting in a 40.9% intracytoplasmic sperm injection (ICSI) fertilization rate (9 embryos/22 MII oocytes). Genetic analysis revealed mutations in seven patients. This study demonstrated the partial efficacy of letrozole-primed IVM plus growth hormone and FSH-hCG primed IVM protocols. No pregnancies or live births were recorded after IVM. One ongoing pregnancy post-IVF and one spontaneous live birth were observed. Conclusion: Inter-cycle variabilities were observed in women with oocyte maturation abnormalities (OMAs). Almost all patients with EFS had oocytes collected during IVM following IVF. These oocytes have limited potential for maturation, fertilization, and live birth, as demonstrated by the low rates observed after IVM culture and ICSI. These conditions are observed in OMAs due to defects in the oocyte machinery. The proposed flowchart provides a comprehensive classification approach for various forms of EFS.

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In vitro maturation (IVM) of oocytes represents an assisted reproductive technique that involves the minimal or absence of ovarian stimulation and is beneficial to specific groups of patients. It is based on the collection of immature cumulus-oocyte complexes (COCs) from antral follicles, which are cultured in vitro until they reach the metaphase II (MII) stage. Once maturation is completed, IVM oocytes are normally fertilized, as during a conventional IVF protocol. On the other hand, ovarian rejuvenation through the intraovarian platelet-rich plasma (PRP) injection represents an innovative procedure intended to restore ovarian fertility and development, and it is used to enhance ovarian stimulation outcomes. Here, we report a case of a 47-year-old woman who underwent an assisted reproductive technology cycle (ART) with PRP injection and IVM, which resulted in a successful pregnancy.

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Objective: This paper serves as an up-to-date narrative review of the most effective methods and outcomes of ovarian tissue cryopreservation (OTC) with new data comparing this method to oocyte and embryo cryopreservation as well as its utility in restoration of endocrine function. Background: Data on OTC are becoming more available as more patients are achieving cancer remission and choosing to use their cryopreserved tissue to conceive or restore endocrine function. With OTC only recently becoming a non-experimental method of fertility preservation, it is important to evaluate, compare, and optimize current practices to improve live birth outcomes. Methods: A literature search of meta-analyses, systematic reviews, case series, retrospective studies, and randomized control trials was performed using the PubMed database with multiple search terms. Discussion: Current practices and outcomes of OTC remain heterogeneous, though they are becoming more streamlined with the emerging data on successful live births. Multiple aspects of OTC have been studied to optimize protocols, particularly methods of cryopreserving, in vitro maturation, and transplantation. In vitro follicle maturation is a novel application with emerging data on methods and outcomes. OTC is a versatile method not only for fertility preservation but also for hormone restoration as well. With wider usage of OTC, ethical dilemmas will need to be addressed. Conclusions: OTC can be used as fertility preservation for a variety of patients. Recent studies suggest it may be comparable to embryo cryopreservation, but with growing data on live births, comparative studies should continue to be performed. In vitro follicle maturation (IVFM) is a promising application of ovarian tissue harvesting. Data are lacking on cost-effectiveness, patient satisfaction, and morbidity associated with OTC.

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This review addresses the current understanding of In Vitro Maturation (IVM) treatment, including indications and effective treatment protocols influencing oocyte developmental competence. A comprehensive literature search was performed to gather relevant studies, clinical trials, and reviews related to IVM. Databases such as PubMed, MEDLINE, and pertinent medical journals were searched. The selected literature was analyzed and synthesized to offer a comprehensive overview. IVM has emerged as a promising technique for inducing maturation in immature oocytes across various developmental stages. Its applications extend to areas utilizing In Vitro Fertilization (IVF), gaining traction as a treatment option for Polycystic Ovary Syndrome (PCOS) and fertility preservation in cancer patients. Recent advancements have led to improved global pregnancy rates, resulting in successful births. IVM also holds potential in reducing risks associated with conventional IVF, including ovarian hyperstimulation syndrome and multiple pregnancies. Despite these advantages, IVM adoption in clinical practice remains limited. Ongoing research aims to refine therapeutic protocols and expand clinical indications. IVM holds promise in assisted reproductive technology, spanning applications from cancer patient fertility preservation to addressing PCOS. Enhanced pregnancy rates highlight efficacy, while risk reduction compared to IVF underscores its importance. Further research is needed for optimal use across patient groups, emphasizing protocol refinement and expanded applications.

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Objectives of the current study were to examine the effects of exogenous expression of PGC-1α, which is a transcription factor responsive for controlling mitochondrial DNA (mtDNA) replication, mitochondria quantity control, mitochondrial biogenesis, and reactive oxygen species (ROS) maintenance, in porcine oocytes during in-vitro maturation (IVM) on the developmental competence, as well as mitochondrial quantity and function. Exogenous over-expression of PGC-1α by injection of the mRNA construct into oocytes 20 h after the start of IVM culture significantly increased the copy number of mtDNA in the oocytes, but reduced the incidences of oocytes matured to the metaphase-II stage after the IVM culture for totally 44 h and completely suppressed the early development in vitro to the blastocyst stage following parthenogenetic activation. The exogenous expression of PGC-1α also significantly induced spindle defects and chromosome misalignments. Furthermore, markedly higher ROS levels were observed in the PGC-1α-overexpressed mature oocytes, whereas mRNA level of SOD1, encoded for a ROS scavenging enzyme, was decreased. These results conclude that forced expression of PGC-1α successfully increase mtDNA copy number but led to increased ROS production, evidently by downregulation of SOD1 gene expression, inducement of spindle aberration/chromosomal misalignment, and consequently reduction in the meiotic and developmental competences of porcine oocytes.

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A 15-year-old female with Hodgkin's lymphoma underwent ovarian tissue cryopreservation for preserving fertility in Reproductive Department of Sir Run Run Shaw Hospital, Zhejiang University School of Medical after receiving one course of chemotherapy. During the ovarian tissue cryopreservation, one MⅡmature oocyte and three germinal vesicle oocytes were found. The three immature oocytes underwent in vitro maturation but failed. Ultimately, one mature oocyte and 12 ovarian cortex slices were cryopreserved using vitrification. This case indicates that for patients with established gonadal axis feedback, ovarian tissue cryopreservation may not be the only method for fertility preservation. It is advisable to consider ovarian stimulation and oocyte retrieval for oocyte cryopreservation. Alternatively, for individuals in the ovulation phase of their menstrual cycle, attempting oocyte retrieval before ovarian tissue cryopreservation to obtain mature oocytes from the natural cycle, followed by oocyte cryopreservation, may enhance the likelihood of successful fertility preservation.

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Oocyte vitrification allows for the storing of endangered breed female gametes. Cryoprotectant (CPA) concentration and exposure time should ensure cell protection with minimal toxicity. In the present study, a high concentration-rapid exposure (HC-RE) and a low concentration-slow exposure (LC-SE) vitrification protocol, using dimethyl sulfoxide (DMSO) and ethylene glycol (EG) as permeating CPAs, were evaluated on meiotic competence and bioenergetic-oxidative status of pre-pubertal lamb immature COCs after in vitro maturation (IVM). For each protocol, COCs vitrified through a traditional protocol and fresh ones were used as controls. Both protocols allowed COC morphology preservation after vitrification-warming (V-W) and cumulus expansion after IVM. The maturation rate (7% and 14%) was comparable to the vitrified control (13% and 21%) but not satisfactory compared to fresh ones (58% and 64%; p < 0.001). The rate of mature oocytes displaying a perinuclear/subcortical (P/S) mitochondrial distribution pattern, an index of cytoplasmic maturity, was comparable between vitrified and fresh oocytes. The LC-SE vitrification protocol did not affect quantitative bioenergetic-oxidative parameters compared to both controls whereas HC-RE protocol significantly reduced intracellular reactive oxygen species (ROS) levels, indicating cell viability loss. In conclusion, to improve pre-pubertal lamb immature COC vitrification, the combination of low CPA concentrations with prolonged exposure time could be more promising to investigate further.

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To obtain high-quality bovine oocytes, the effects of vitamin C (VC) on the IVM of bovine oocytes and early embryo development were investigated. The results showed the following. (1) The IVM medium containing 50 µg/mL VC improved the oocyte maturation rate but did not affect the parthenogenetic embryo development. (2) The IVC medium containing 20 µg/mL VC improved the cleavage rate of the IVF embryos and enhanced the mRNA transcriptions of pluripotency gene Oct4, Sox2, Cdx2, and Nanog in the blastocysts but had no effects on the blastocyst rate. (3) Combining supplementation of 50 µg/mL VC in IVM medium + 20 µg/mL VC in IVC medium (named as VC 50/20, similar hereinafter) elevated the cleavage rate of IVF embryos and enhanced the mRNA expressions of Oct4, Sox2, Cdx2, and Nanog in the blastocysts. (4) Combination of VC 0/20 and VC 50/20 enhanced the transcription of anti-apoptotic gene Bcl-2 and VC 50/0 weakened the transcription of pro-apoptotic gene Bax, while VC 0/40 and VC 0/60 increased Bax expression and diminished the Bcl-2/Bax ratio in blastocysts. Together, employing 50 µg/mL VC improves the IVM of bovine oocytes and combination of VC 50/20 potentially changes bovine embryo quality by enhancing the expressions of the pluripotency genes and regulating the expressions of apoptosis-related genes.

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In vitro maturation of oocytes (IVM) represents an assisted reproductive technique that involves the minimal or absence of ovarian stimulation and is beneficial to specific groups of patients. These may include women with polycystic ovarian syndrome and/or patients who need a fertility preservation option before undergoing gonadotoxic treatment. However, when IVM is applied in cases where it is not recommended, it can be considered as an add-on technique, as described by the ESHRE Guideline Group on Female Fertility Preservation. Interestingly, IVM has not been proven yet to be as effective as conventional IVF in the laboratory, in terms of clinical pregnancy and live birth rates, while concerns have been raised for its long-term safety. As a result, both safety and efficacy of IVM remain still questionable and additional data are needed to draw conclusions.

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Background: Amphiregulin (AR) is a growth factor that resembles the epidermal growth factor (EGF) and serves various functions in different cells. However, no systematic studies or reports on the role of AR in human oocytes have currently been performed or reported. This study aimed to explore the role of AR in human immature oocytes during in vitro maturation (IVM) and in vitro fertilization (IVF) in achieving better embryonic development and to provide a basis for the development of a pre-insemination culture medium specific for cumulus oocyte complexes (COCs). Methods: First, we examined the concentration of AR in the follicular fluid (FF) of patients who underwent routine IVF and explored the correlation between AR levels and oocyte maturation and subsequent embryonic development. Second, AR was added to the IVM medium to culture immature oocytes and investigate whether AR could improve the effects of IVM. Finally, we pioneered the use of a fertilization medium supplemented with AR for the pre-insemination culture of COCs to explore whether the involvement of AR can promote the maturation and fertilization of IVF oocytes, as well as subsequent embryonic development. Results: A total of 609 FF samples were examined, and a positive correlation between AR levels and blastocyst formation was observed. In our IVM study, the development potential and IVM rate of immature oocytes, as well as the fertilization rate of IVM oocytes in the AR-added groups, were ameliorated significantly compared to the control group (All P < 0.05). Only the IVM-50 group had a significantly higher blastocyst formation rate than the control group (P < 0.05). In the final IVF study, the maturation, fertilization, high-quality embryo, blastocyst formation, and high-quality blastocyst rates of the AR-added group were significantly higher than those of the control group (All P < 0.05). Conclusion: AR levels in the FF positively correlated with blastocyst formation, and AR involvement in pre-insemination cultures of COCs can effectively improve laboratory outcomes in IVF. Furthermore, AR can directly promote the in vitro maturation and developmental potential of human immature oocytes at an optimal concentration of 50 ng/ml.

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PURPOSE: To assess the developmental competence of oocytes matured following rescue in vitro maturation (IVM). METHODS: PubMed, EmBASE, and SCOPUS were systematically searched for peer-reviewed original papers using relevant keywords and Medical Subject Heading terms. Study quality was assessed using the Newcastle-Ottawa Scale. Odds ratios with a 95% confidence interval were calculated by applying a random effects model. The primary outcomes were fertilization and blastulation rates. Secondary outcomes included abnormal fertilization, cleavage, euploidy, clinical pregnancy, and live-birth rates. RESULT: Twenty-four studies were included in the meta-analysis. The oocytes matured following rescue IVM showed significantly reduced fertilization, cleavage, blastulation, and clinical pregnancy rates compared to sibling in vivo-matured oocytes. No significant differences were found for the euploidy and live-birth rates in euploid blastocyst transfer. In poor responders, a reduced fertilization rate was observed using in vitro-matured GV but not with in vitro-matured MI. A reduced cleavage rate in MI matured overnight compared to < 6 incubation hours was found. CONCLUSION: Our results showed compromised developmental competence in oocytes matured following rescue IVM. However, in poor responders, rescue IVM could maximize the efficiency of the treatment. Notably, our data suggests using in vitro MI matured within 6 incubation hours. CLINICAL TRIAL REGISTRATION NUMBER: CRD42023467232.

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Polycystic ovary syndrome (PCOS) is an endocrinological disorder affecting women of reproductive age, characterized by hormonal imbalance leading to metabolic and reproductive dysregulations. This case report revolves around a 30-year-old husband and his 27-year-old partner. The male partner had normozoospermia, and the female spouse had PCOS, according to the couple's diagnostic evaluations. The female patient received ovarian stimulation specifically to assist with PCOS, and the retrieved oocytes were then matured in vitro. After intracytoplasmic sperm injection (ICSI), fertilization and embryonic development were successful. Treatment of PCOS-related infertility presents many challenges, and in vitro maturation (IVM) and its potential as an effective assisted fertility method are discussed. To optimize treatment outcomes, the conclusion shows the importance of IVM and other assisted reproductive techniques for infertility. It also focuses on the necessary continuous research and clinical experience. Clinical pregnancy was confirmed by measuring serum beta-human chorionic gonadotropin (ß-hCG) levels followed by ultrasound sonography (USG), which showed a normal growth rate of the fetus.

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Purpose: In vitro maturation (IVM) of oocytes obtained from ovarian tissue during ovarian tissue cryopreservation (OTC) is a technique for fertility preservation in patients with cancer obviating the need to postpone chemotherapy initiation. Little is known about IVM outcomes in hematological malignancies, especially post-chemotherapy. The purpose of this study was to evaluate the effect of cytotoxic treatment on the potential to retrieve immature oocytes and mature them in vitro and examine the association between serum inflammatory markers and these results. Methods: In this retrospective study, we evaluated inflammation markers, including B symptoms and IVM outcomes of 78 chemotherapy-naive and exposed patients diagnosed with Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), acute lymphoblastic leukemia (ALL), or acute myeloid leukemia (AML). Results: The mean number of oocytes found was 7.2 ± 7.2. The average number of oocytes matured by IVM was 2.8 ± 3.5, and a mean IVM rate was 32.1 ± 27.7%. All patients in the ALL and AML groups had previous exposure to chemotherapy before OTC, compared with 50.0% (7/14) and 31.9% (15/47) in the NHL and HL groups, respectively. Among patients with lymphoma, chemotherapy exposure was associated with the reduced number of retrieved oocytes (9.8 ± 7.7 vs. 5.3 ± 5.7 oocytes, p = 0.049) in the HL group but not with the number of mature oocytes or IVM rate. B symptoms were not associated with IVM outcomes. Lymphocyte count (ß = 1.584; p = 0.038) and lactate dehydrogenase (ß = 0.009; p = 0.043) were the only significant parameters associated with the number of matured oocytes in a linear regression model. Conclusion: IVM is a promising assisted reproductive technology, which holds great potential for patients in need of urgent fertility preservation or those who cannot receive hormonal stimulation. Our results demonstrate the feasibility of the technique even in the presence of B symptoms and elevated inflammation markers and in patients with previous exposure to chemotherapy.

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The in vitro maturation (IVM) rate of canine oocytes remains low compared to other mammals due to their unique reproductive characteristics. This study aimed to explore the effect of hormone supplementation during the IVM of canine immature oocytes on nuclear maturation and subsequently assess its potential application in canine somatic cell nuclear transfer (SCNT). Immature oocytes were collected and cultured in an IVM medium supplemented with hormones (follicle-stimulating hormone [FSH] and progesterone [P4]) or without hormones (control) for 24 hours. The maturation rates of oocytes in the hormone-treated group (94.92 ± 3.15%) were significantly higher than those in the control group (61.01 ± 4.23%). Both in vitro and in vivo matured oocytes underwent NT to evaluate their utility, and the fusion rates were higher in the in vitro matured group than those in the vivo matured group, not significant between in vivo and in vitro matured group (73.28% and 82.35%, respectively). As a result, 14 fused embryos from the in vitro matured group were transferred into two surrogates, with one surrogate achieving a successful pregnancy and delivering four puppies. Whereas in the in vivo matured group, 85 fused embryos were transferred to 8 surrogate mothers, leading to three surrogates becoming pregnant and delivering one, four, and two puppies. The pregnancy rates were not significant between both groups (50% and 37.50%), but the number of offspring exhibited a significant difference (28.57% and 8.23%). In conclusion, we achieved a remarkable milestone by successfully producing cloned puppies using in vitro matured oocytes, underscoring the feasibility of canine cloning from in vitro recovered oocytes. It is important to note that this study focused only on immature oocytes after ovulation and only during the estrus stage. Further research targeting other stages of the estrous cycle could potentially enhance canine cloning efficiency.

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In assisted reproduction techniques, oocytes encounter elevated levels of reactive oxygen species (ROS) during in vitro maturation (IVM). Oxidative stress adversely affects oocyte quality, hampering their maturation, growth, and subsequent development. Thus, mitigating excessive ROS to safeguard less viable oocytes during IVM stands as a viable strategy. Numerous antioxidants have been explored for oocyte IVM, yielding considerable effects; however, several aspects, including solubility, stability, and safety, demand attention and resolution. In this study, we developed nanoparticles by self-assembling endogenous bilirubin and melatonin hormone coated with bilirubin-conjugated glycol chitosan (MB@GBn) to alleviate oxidative stress and enhance oocyte maturation. The optimized MB@GBn exhibited a uniform spherical shape, measuring 128 nm in particle size, with a PDI value of 0.1807 and a surface potential of +11.35 mV. The positively charged potential facilitated nanoparticle adherence to the oocyte surface through electrostatic interaction, allowing for functional action. In vitro studies demonstrated that MB@GB significantly enhanced the maturation of compromised oocytes. Further investigation revealed MB@GB's effectiveness in scavenging ROS, reducing intracellular calcium levels, and suppressing mitochondrial polarization. This study not only offers a novel perspective on nano drug delivery systems for biomedical applications but also presents an innovative strategy for enhancing oocyte IVM.

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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.

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Objective: This study aims to investigate the developmental potential of immature oocytes and questions whether unstimulated in vitro maturation (IVM) can be used as a treatment in women with oocyte maturation abnormalities. Material and Methods: This cohort study was conducted between September 2019 and December 2022, and it included 12 women who underwent unstimulated, non-hCG priming IVM.Oocytes were incubated in in vitro maturation medium for 26-48 hours and evaluated to compare their maturation profiles with the immature oocytes retrieved from the same patients in their previous IVF cycles. Results: Among the twelve women in the study, eleven (91.6%) underwent whole exome sequencing (WES) analysis. Of these, ten women presented a total of 18 mutations, excluding Case 1, which had no previous mutation analysis. Of the mutations identified, 9 (50%) were located in the FSHR gene, 5 (27.8%) in the TUBB8 gene, 1 (5.6%) in the ZP1 gene, 1 (5.6%) in the SLFN14 gene, 1 (5.6%) in the AR gene, and 1 (5.6%) in the STEAP3 gene. Apart from one woman with resistant ovary syndrome,none of the women treated with unstimulated in vitro maturation had oocyte maturation . Remarkably, the only patient to achieve oocyte maturation in an unstimulated IVM cycle was Case 11, who had ROS and a single FSHR mutation. Conclusion: Unstimulated non hCG primed IVM has no value in the treatment of OMAS, except in cases with resistant ovary syndrome. However this study led our team to develop novel treatment options based on physiological mechanisms for some subtypes and supraphysiological approach for other subtypes of oocyte maturation abnormalities.