BACKGROUNDOocyte vitrification is widely used throughout the world, but its clinical efficacy is inconsistent and depends on the vitrification media. This study compared the developmental potential and clinical results of in vivo matured oocytes cryopreserved with different vitrification media.

METHODSThis retrospective study involved vitrified-warmed oocytes at one in vitro fertilization laboratory. Vitrification media kits comprised the MC kit (ethylene glycol [EG] plus 1,2-propanediol [PROH]), the KT kit (EG plus dimethyl sulphoxide [DMSO]), and the Modified kit (EG plus DMSO and PROH kit). Rates of oocyte survival and subsequent developmental potential were recorded and analyzed. The t-test and the Chi-square test were used to evaluate each method's efficacy.

RESULTSOocyte survival rate was significantly higher for the Modified kit (92.0%) than for the MC kit (88.2%) (P < 0.05) and the KT kit (77.3%) (P < 0.001). The rate of high-quality embryo development in the Modified kit group (35.8%) was significantly higher than in the MC kit group (29.0%) and the KT kit group (28.3%) (P < 0.001). No significant differences were observed in the clinical pregnancy and implantation rates among the MC, KT, and Modified kit groups (37.2% vs. 30.2% vs. 39.6%; 21.9% vs. 18.8% vs. 27.4%, respectively) (P > 0.05). The high-quality embryo rate per warmed oocyte was significantly higher (23.4%) in the Modified kit group than in the other groups (P < 0.001). The embryo utilization and live birth rates per warmed oocyte were the highest in the Modified kit group, but not significantly (P > 0.05).

CONCLUSIONSModified vitrification media are efficient for oocyte vitrification and, with further verification, may be able to replace commercially available media in future clinical applications.

Adult ; Cryopreservation ; methods ; Female ; Fertilization in Vitro ; methods ; Humans ; In Vitro Oocyte Maturation Techniques ; methods ; Oocytes ; cytology ; Pregnancy ; Retrospective Studies ; Vitrification

AIMTo study whether melatonin has effect on oocyte maturation of mouse in vitro.

METHODSMouse oocytes were cultured in maturation medium, HX-medium, or HX-medium supplemented with FSH, and the effects of MT on meiotic maturation of mouse oocyte were examined.

RESULTS(1) MT at all doses of 0.1 g/L, 0.02 g/L, 0.4 g/L or 0.8 g/L inhibited the formation of PB1 in CEO cultured in maturation medium and had no effect on GVBD. (2) MT could delay GVBD and the extrusion of PB1 in CEOs of mouse oocytes by dynamic curves. In contrast to the control, GVBD and PB1 extrusion of oocytes in the treated groups had been delayed by 8-10 hours and 3-4 hours respectively. (3) MT inhibited the effect of FSH on resumption of meiosis, but no effect on the formation of PB1. (4) MT and HX had cooperation effects on spontaneous oocyte maturation in CEO, but not in DO.

CONCLUSIONMT is able to affect mouse oocyte maturation and the regulation mechanisms may be related to cumulus cells.

Animals ; Female ; In Vitro Oocyte Maturation Techniques ; Melatonin ; pharmacology ; Mice ; Mice, Inbred Strains ; Oocytes ; drug effects ; physiology ; Oogenesis ; drug effects

Oocyte in vitro maturation (IVM) is an assisted reproductive technology in which oocytes are retrieved from the antral follicles of unstimulated or minimally stimulated ovaries. IVM of human oocytes has emerged as a promising procedure. This new technology has advantages over controlled ovarian stimulation such as reduction of costs, simplicity, and elimination of ovarian hyperstimulation syndrome. By elimination or reduction of gonadotropin stimulation, IVM offers eligible infertile couples a safe and convenient form of treatment, and IVM outcomes are currently comparable in safety and efficacy to those of conventional in vitro fertilization. IVM has been applied mainly in patients with polycystic ovary syndrome or ultrasound-only polycystic ovaries, but with time, the indications for IVM have expanded to other uncommon situations such as fertility preservation, as well as to normal responders. In this review, the current clinical experiences with IVM will be described.
Family Characteristics ; Female ; Fertility Preservation ; Fertilization in Vitro ; Gonadotropins ; Humans ; In Vitro Oocyte Maturation Techniques ; Infertility ; Oocytes ; Ovarian Hyperstimulation Syndrome ; Ovary ; Ovulation Induction ; Polycystic Ovary Syndrome ; Reproductive Techniques, Assisted

OBJECTIVE: The aims of this study were to investigate whether fertilization could induce the resumption of meiosis in mouse oocytes arrested at metaphase I (MI) after in vitro maturation (IVM), and to investigate the effect of Ca²⁺ chelator treatment at the time of fertilization on the transition from MI to metaphase II (MII). METHODS: MII-stage and arrested MI-stage mouse oocytes after IVM were fertilized, and then embryonic development was monitored. Blastocysts from each group were transferred into 2.5 days post-coitum pseudo-pregnant ICR mice. MI oocytes after IVM were treated with a Ca²⁺ chelator to investigate the effect of Ca²⁺ oscillations on their maturation. RESULTS: As insemination time increased, the number of oocytes in the MI group that reached the MII stage also increased. The blastocyst rates and total cell numbers in the MII group were significantly higher than in the MI group. No pregnancy occurred in the MI group, but 10 pregnancies were achieved (10 of 12) in the MII group. The proportion of MI oocytes that matured to MII oocytes after fertilization was significantly higher in the non-treated group than in the Ca²⁺ chelator-treated group. CONCLUSION: The findings that a higher proportion of MI-arrested oocytes progressed to MII after fertilization and that the MI-to-MII transition was blocked by Ca2+ chelator treatments before fertilization indicate that the maturation of MI oocytes to MII oocytes is associated with intracellular Ca²⁺ oscillations driven by fertilization.
Animals ; Blastocyst ; Calcium Signaling ; Cell Count ; Embryonic Development ; Female ; Fertilization ; In Vitro Oocyte Maturation Techniques ; In Vitro Techniques* ; Insemination* ; Meiosis ; Metaphase* ; Mice* ; Mice, Inbred ICR ; Oocytes* ; Pregnancy ; Spermatozoa*

OBJECTIVE: The aim of this study was to report a case series of in vitro matured (IVM) oocyte freezing in gynecologic cancer patients undergoing radical surgery under time constraints as an option for fertility preservation (FP). METHODS: Case series report. University-based in vitro fertilization center. Six gynecologic cancer patients who were scheduled to undergo radical surgery the next day were referred for FP. The patients had endometrial (n=2), ovarian (n=3), and double primary endometrial and ovarian (n=1) cancer. Ex vivo retrieval of immature oocytes from macroscopically normal ovarian tissue was followed by mature oocyte freezing after IVM or embryo freezing with intracytoplasmic sperm injection. RESULTS: A total of 53 oocytes were retrieved from five patients, with a mean of 10.6 oocytes per patient. After IVM, a total of 36 mature oocytes were obtained, demonstrating a 67.9% maturation rate. With regard to the ovarian cancer patients, seven IVM oocytes were frozen from patient 3, who had stage IC cancer, whereas one IVM oocyte was frozen from patient 4, who had stage IV cancer despite being of a similar age. With regard to the endometrial cancer patients, 15 IVM oocytes from patient 1 were frozen. Five embryos were frozen after the fertilization of IVM oocytes from patient 6. CONCLUSION: Immature oocytes can be successfully retrieved ex vivo from macroscopically normal ovarian tissue before radical surgery. IVM oocyte freezing provides a possible FP option in patients with advanced-stage endometrial or ovarian cancer without the risk of cancer cell spillage or time delays.
Cryopreservation* ; Embryonic Structures ; Endometrial Neoplasms ; Female ; Fertility Preservation ; Fertilization ; Fertilization in Vitro ; Freezing ; Humans ; In Vitro Oocyte Maturation Techniques ; In Vitro Techniques* ; Oocyte Retrieval* ; Oocytes* ; Ovarian Neoplasms ; Sperm Injections, Intracytoplasmic ; Uterine Neoplasms

Brain-derived neurotrophic factor (BDNF) can promote developmental competence in mammalian oocytes during in vitro maturation (IVM), but the role of BDNF in oocyte maturation at cellular level is not still clear. In this study, mouse cumulus-enclosed oocytes subjected to IVM were fertilized and cultured to blastocyst stage. Meiotic spindle configuration and cortical granules distribution during oocyte maturation in vitro were assessed by using immunofluorescence and laser confocal microscopy. The results showed that BDNF contributed to the complete preimplantation development of mouse oocytes compared to the control oocytes (13.78% vs. 5.92%; P<0.05). Further, BDNF did not accelerate nuclear maturation of IVM oocytes. For the BDNF-treated oocytes at meiosis I, Meiotic spindle areas were significantly smaller and the number of cytoplasmic microtubule organizing centers was greater than that in the control, and the percentages of oocytes showed spindles positioned near the oolemma and a well-formed cortical granule-free domain were significantly higher than that of the control. These morphological characteristics of the BDNF-treated oocytes were much closer to the oocytes matured in vivo than those of the control oocytes. In conclusion, BDNF can promote the developmental competence of mouse IVM oocytes, by improving the meiotic spindle configuration and location and cortical granules distribution at meiosis 1.
Animals ; Blastomeres ; cytology ; Brain-Derived Neurotrophic Factor ; pharmacology ; Female ; Fertilization in Vitro ; In Vitro Oocyte Maturation Techniques ; methods ; Male ; Mice ; Oocysts ; growth & development

OBJECTIVE: In order to increase the number of mature oocytes usable for intracytoplasmic sperm injection (ICSI), we aimed to investigate the effect of co-culturing granulosa cells (GCs) on human oocyte maturation in vitro, the fertilization rate, and embryo development. METHODS: A total of 133 immature oocytes were retrieved and were randomly divided into two groups; oocytes that were cultured with GCs (group A) and oocytes that were cultured without GCs (group B). After in vitro maturation, only oocytes that displayed metaphase II (MII) underwent the ICSI procedure. The maturation and fertilization rates were analyzed, as well as the frequency of embryo development. RESULTS: The mean age of the patients, their basal levels of follicle-stimulating hormone, and the number of oocytes recovered from the patients were all comparable between the two study groups. The number of oocytes that reached MII (mature oocytes) was 59 out of 70 (84.28%) in group A, compared to 41 out of 63 (65.07%) in group B (p=0.011). No significant difference between fertilization rates was found between the two study groups (p=0.702). The embryo development rate was higher in group A (33/59, 75%) than in group B (12/41, 42.85%; p=0.006). The proportion of highest-quality embryos and the blastocyst formation rate were significantly lower in group B than in group A (p=0.003 and p<0.001, respectively). CONCLUSION: The findings of the current study demonstrate that culturing immature human oocytes with GCs prior to ICSI improves the maturation rate and the likelihood of embryo development.
Blastocyst ; Coculture Techniques* ; Embryonic Development* ; Embryonic Structures* ; Female ; Fertilization ; Follicle Stimulating Hormone ; Granulosa Cells* ; Humans* ; In Vitro Oocyte Maturation Techniques ; Metaphase ; Oocytes* ; Pregnancy ; Sperm Injections, Intracytoplasmic

This study was conducted to investigate the effects of rapamycin treatment during in vitro maturation (IVM) on oocyte maturation and embryonic development after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT) in pigs. Morphologically good (MGCOCs) and poor oocytes (MPCOCs) were untreated or treated with 1 nM rapamycin during 0-22 h, 22-42 h, or 0-42 h of IVM. Rapamycin had no significant effects on nuclear maturation and blastocyst formation after PA of MGCOCs. Blastocyst formation after PA was significantly increased by rapamycin treatment during 22-42 h and 0-42 h (46.6% and 46.5%, respectively) relative to the control (33.3%) and 0-22 h groups (38.6%) in MPCOCs. In SCNT, blastocyst formation tended to increase in MPCOCs treated with rapamycin during 0-42 h of IVM relative to untreated oocytes (20.3% vs. 14.3%, 0.05 < p < 0.1), while no improvement was observed in MGCOCs. Gene expression analysis revealed that transcript abundance of Beclin 1 and microtubule-associated protein 1 light chain 3 mRNAs was significantly increased in MPCOCs by rapamycin relative to the control. Our results demonstrated that autophagy induction by rapamycin during IVM improved developmental competence of oocytes derived from MPCOCs.
Animals ; Embryonic Development/*drug effects ; Female ; In Vitro Oocyte Maturation Techniques/veterinary ; Nuclear Transfer Techniques/*veterinary ; Oocytes/growth & development ; *Parthenogenesis ; Sirolimus/*pharmacology ; Sus scrofa/*growth & development/metabolism

Oocytes retrieval, in vitro maturation (IVM) and fertilization (IVF) efficiency are inevitable steps towards in vitro production of embryos. In the present study, these parameters were investigated in the ovaries of prepubertal (n = 31) and pubertal (n = 61) black Bengal goats obtained from a slaughterhouse. Nuclear maturation was evaluated upon aspiration and following IVM in TCM-199 (Earle's salt with L-glutamine and sodium bicarbonate) for 27 h at 39degrees C under 5% CO2 in humidified air. The oocytes retrieval and efficiency (mean +/- SD) per prepubertal and pubertal goats were 5.2 +/- 0.6 and 6.8 +/- 0.6, and 77.3 +/- 0.1% and 80.5 +/- 0.6%, respectively. Anaphase I - telophase I stages differed significantly (7.3 +/- 0.8 vs. 2.6 +/- 0.2, p < 0.05) between the two groups of goats. After IVM, the percentages of metaphase II were significantly higher (66.3 vs. 60.3, p < 0.05) in pubertal goats than in their prepubertal counterparts. The percentages of normal in vitro fertilization (IVF) in Fert-Tyrode's albumin lactate pyruvate of pubertal goat oocytes did not differ between Percoll and swim-up sperm separation methods (36.7 +/- 0.9% vs. 32.7 +/- 1.3%, p > 0.05). Furthermore, sperm capacitation by heparin alone or in combination with ionomycin did not lead to a significant increase in the normal fertilization rate (34.8 +/- 1.7 vs. 32.2 +/- 1.5%, respectively) in the oocytes of pubertal goats. In conclusion, the ovaries of pubertal black Bengal goats obtained from the slaughterhouse could be used for in vitro embryo production. However, further optimization of the IVM and IVF techniques are necessary for satisfactory in vitro embryo production.
Animals ; Culture Techniques ; Embryonic Development/*physiology ; Female ; Fertilization in Vitro/*veterinary ; Goats/*embryology ; Male ; Oocyte Retrieval/veterinary ; Oocytes/*physiology ; Ovary/cytology ; Sexual Maturation ; Sperm Capacitation ; Tissue and Organ Harvesting/veterinary

Quercetin is a plant-derived flavonoid found in fruits or vegetables that has antioxidant properties and acts as a free radical scavenger. We investigated the effects of quercetin on porcine oocyte nuclear maturation and embryonic development after parthenogenetic activation. We then evaluated the antioxidant activities of quercetin by measuring reactive oxygen species (ROS) levels in matured oocytes. Immature oocytes were untreated or treated with 1, 10, and 50 microg/mL quercetin during in vitro maturation (IVM). Quercetin treatment did not improve oocyte nuclear maturation, but significantly higher blastocyst rates (p < 0.05) of parthenogenetically activated oocytes were achieved when the IVM medium was supplemented with an adequate concentration of quercetin (1 microg/mL). However, cleavage rates and blastocyst cell numbers were not affected. Oocytes treated with 1 or 10 microg/mL quercetin had significantly lower (p < 0.05) levels of ROS than the control and group treated with the highest concentration of quercetin (50 microg/mL). Moreover, this highest concentration was detrimental to oocyte nuclear maturation and blastocyst formation. Based on our findings, we concluded that exogenous quercetin reduces ROS levels during oocyte maturation and is beneficial for subsequent embryo development.
Animals ; Antioxidants/administration & dosage/*pharmacology ; Dose-Response Relationship, Drug ; In Vitro Oocyte Maturation Techniques/*veterinary ; Oocytes/cytology/*drug effects/physiology ; Quercetin/administration & dosage/*pharmacology ; Reactive Oxygen Species/*metabolism ; *Swine