Maturation Of Immature Human Oocytes Research Articles

Oocyte diameter predicts the maturation rate of human immature oocytes collected ex vivo

PurposeTo study the impact of oocyte diameter and cumulus cell mass on the potential for final maturation of immature human oocytes in vitro.MethodsImmature oocytes (n = 1563) from 75 women undergoing fertility preservation by ovarian tissue cryopreservation (14–41 years) were collected. After preparation of the ovarian cortex for freezing, immature oocytes were collected from the surplus medulla. After collection, IVM was performed according to standard published methods. The mass of cumulus cell surrounding the immature oocyte was grouped according to size. After IVM, each oocyte was photographed, measured, and the diameter was calculated as a mean of two perpendicular measurements.ResultsThe diameter of the oocytes ranged from 60 to 171 µm with a mean of 115 µm (SD:12.1) and an interquartile range from 107 to 124 µm. The oocyte diameter was positively associated with a higher incidence of MII (p < 0.001). MII oocytes had a significantly larger mean diameter than MI, GV, and degenerated oocytes. The size of the cumulus cell mass was significantly associated with the MII stage (p < 0.001) and larger oocyte diameter (p < 0.001). The results further confirm that the diameter of the fully grown oocyte is reached relatively early in human follicular development and that the factors governing oocyte maturation in vitro are connected to the surrounding cell mass and the oocyte.ConclusionThe diameter of the oocyte is a highly determining factor in the nuclear maturation of the human oocyte during in vitro maturation, and the size of the cumulus cell mass is closely positively associated with a larger diameter.

CoQ10 decreases aneuploidy rate and increases mitochondrial mass during in vitro maturation of human immature oocytes

CoQ10 decreases aneuploidy rate and increases mitochondrial mass during in vitro maturation of human immature oocytes

In vitro maturation of human immature oocytes for fertility preservation and research material

AimIn recent years, the importance of fertility preservation (FP) has increased. In vitro maturation (IVM), an important technique in FP, has started to be used in the clinic, but controversies persist regarding this technique. Here, a survey of IVM for FP is provided.MethodsBased on a literature review, the applications of FP, methods of FP, IVM of oocytes that had been collected in vivo and ex vivo, maturation of oocytes after IVM for FP, cryopreservation of oocytes for FP, explanation of the procedures to patients, and recent research on FP using IVM were investigated.ResultsAlthough IVM for FP remains controversial, the application of FP is expected to expand. Depending on the age and disease status of the patient, various methods of oocyte collection and ovarian stimulation, as well as various needle types and aspiration pressures, have been reported. The maturation rate of IVM in FP ranges widely and requires optimization in the future. In regard to cryopreservation for matured oocytes, the vitrification method is currently recommended.ConclusionRegarding FP for patients with cancer, the treatment of cancer is prioritized; thus, the time and use of medicines are often constrained. As several key points regarding IVM remain unclear, well‐designed and specific counseling for patients is necessary.

Comparison of blastocyst and Sage media for in vitro maturation of human immature oocytes.

In vitro maturation (IVM) of human oocytes is an attractive alternative to conventional assisted reproductive technology (ART) treatment, as it involves no or minimal ovarian stimulation. Currently, commercialized media specifically designed for IVM are often used. These media are expensive, have limited shelf life, and must be ordered in advance. If standard culture media can be used in place of the specialized IVM media, it would simplify management and make IVM more feasible and more widely employed in ART centers around the world, especially in developing countries where resources are scarce. This study was, therefore, conducted to test the hypothesis that blastocyst medium was as good as commercial IVM medium to support maturation and developmental competence of human immature oocytes as previously shown in the mouse system. Immature oocytes were obtained by needle aspiration from 89 pregnant women during cesarean deliveries between April 2012 and February 2013. Sibling oocytes were allocated to Sage IVM media (512 oocytes) or blastocyst medium (520 oocytes) and assessed for maturation 36 hours later. Mature oocytes were inseminated by intracytoplasmic sperm injection and cultured up to 144 hours. There was no difference in maturation rate (65.0% vs 68.7%; P = .218) or fertilization rate (66.9% vs 66.4%; P = .872) of oocytes matured in vitro in both media. There was also no difference in the formation of good-quality blastocysts (46.6% vs 45.9%; P = .889) in the 2 groups. Further study should be done to ascertain implantation and pregnancy potential of these embryos.

In vitro maturation of immature human oocytes for clinical application.

Meiotic progression in the oocyte is defined as oocyte maturation from reinitiation of the first meiotic division from the germinal vesicle (GV) stage to the metaphase-II (M-II) stage (Fig. 1), (Cha and Chian, Hum Reprod Update 4:103-120, 1998). Priming with FSH or HCG prior to immature oocyte retrieval improves oocyte maturation and pregnancy rates. The size of follicles may be an important feature for IVM treatment. The combination of natural-cycle IVF with immature oocyte retrieval followed by IVM is an attractive treatment for young women with all types of infertility without recourse to ovarian stimulation with an acceptable pregnancy rate.

Does supplementation of in-vitro culture medium with melatonin improve IVF outcome in PCOS?

Human pre-ovulatory follicular fluid (FF) contains a higher concentration of melatonin than serum. The aim of this study was to evaluate the effect of melatonin supplementation of culture medium on the clinical outcomes of an in-vitro maturation (IVM) IVF-embryo transfer programme for patients with polycystic ovarian syndrome (PCOS). Melatonin concentrations in the culture media of granulosa cells (GC) or cumulus-oocyte-complexes (COC) were measured and the clinical outcomes after using IVM media with or without melatonin were analysed. In the culture media of GC or COC, melatonin concentrations gradually increased. When human chorionic gonadotrophin priming protocols were used, implantation rates in the melatonin-supplemented group were higher than those of the non-supplemented control group (P<0.05). Pregnancy rates were also higher, although not significantly. The findings suggest that the addition of melatonin to IVM media may improve the cytoplasmic maturation of human immature oocytes and subsequent clinical outcomes. It is speculated that follicular melatonin may be released from luteinizing GC during late folliculogenesis and that melatonin supplementation may be used to improve the clinical outcomes of IVM IVF-embryo transfer.Melatonin is primarily produced by the pineal gland and regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. Interestingly, human pre-ovulatory follicular fluid contains a higher concentration of melatonin than serum. However, in contrast to animal studies, the direct role of melatonin on oocyte maturation in the human system has not yet been investigated. So, the aim of the study was to evaluate the effect of melatonin supplementation of culture medium on the clinical outcome of an in-vitro maturation (IVM) IVF-embryo transfer programme for PCOS patients. The melatonin concentrations in culture medium of granulosa cells (GC) or cumulus-oocyte-complexes (COC) were measured and the clinical outcomes of IVM IVF-embryo transfer using IVM medium alone or supplemented with melatonin were analysed. In the culture media of GC or COC, the melatonin concentration gradually increased. With human chorionic gonadotrophin priming, the pregnancy and implantation rates in the melatonin-supplemented group were higher than those of the non-supplemented control (P<0.05). Our findings suggest that follicular melatonin is released from luteinizing GC during late folliculogenesis and plays a positive role in oocyte maturation. Therefore, addition of melatonin into IVM medium may improve cytoplasmic maturation of human immature oocytes and subsequent clinical outcomes.

Clinical application of in vitro maturation of human immature oocytes for infertile women with polycystic ovary syndrome

To investigate clinical effect and safety of in vitro maturation (IVM) of human immature oocytes in infertile women with polycystic ovary syndrome by comparing with conventional in vitro fertilization(IVF)and intracytoplasmic sperm injection(ICSI). From Jan. 2003 to Dec. 2009, 157 infertile women with PCOS underwent 162 cycles IVM in Center for Reproductive Medicine, the First Affiliated Hospital of Anhui Medical University. In the mean time, 109 patients with PCOS underwent 114 IVF/ICSI cycles as control group 1 and 106 patients with other factors underwent 106 IVF/ICSI cycles as control group 2. Treatment and outcome of pregnancy and infant were compared among those 3 groups. No statistically significant difference were found in terms of the positive rate of hCG in urine [35.7% (56/157), 42.2% (46/109), 44.3% (47/106)], the rate of clinical pregnancy [29.3% (46/157), 37.6% (41/109), 41.5% (44/106)], the rate of entopic pregnancy [1.9% (3/157), 1.8% (2/109), 0.9% (1/106)], the rate of miscarriage [18.6% (8/43), 12.8% (5/39), 20.9% (9/43)] and the rate of live-birth [22.3% (35/157), 31.2% (34/109), 32.1% (34/106)] among three groups (IVM group, control group 1, control group 2, P > 0.05). The rate of preterm labor, low weight newborn, mean birth weight, ratio of male to female did not show significantly difference among 3 groups (P > 0.05). The average control ovarian stimulation was 6 days, the median dose of gonadotropin (Gn) was 675 IU, and the total hospital cost was (8392 ± 1328) RMB in IVM group, which were statistically lower than those in the other two control groups (P < 0.01). The rate of multiple pregnancy was 4.7% (2/43) and ovarian hyperstimulation syndrome (OHSS) 0 in IVM group, which were significantly lower than those in the other control group (P < 0.01). In vitro maturation is an effective treatment in infertile women with PCOS, it could obtain the similar pregnancy outcome and reduce total cost, the dosage of gonadotropin-releasing hormone and rate of OHSS compared with conventional IVF/ICSI.

In Vitro Maturation of Human Immature Oocytes

Ovarian stimulation regimes may be hazardous to a small proportion of women or may result in side effects. For such women IVM is recommended. IVM technology can be divided into two main approaches, namely (i) FSH and (ii) hCG priming. These two approaches improve oocyte maturation and pregnancy rates when the immature oocytes are retrieved from women with PCOS. Although the size of follicles appears to be important for subsequent embryonic development however the developmental competence of oocytes derived from the small antral follicles seems not to be adversely affected by the presence of a dominant follicle. In general, the clinical pregnancy and implantation rates per ET are now in the order of 35–40% and 10–15% respectively in women with PCOS following IVM. The combination of natural cycle IVF with immature oocyte retrieval followed by IVM is an attractive treatment alternative for women with various forms of infertility without recourse to ovarian stimulation. Natural cycle IVF/M together with IVM alone can be used to treat more than half of the population of infertile patients with acceptable pregnancy rate. Approximately 2,000 healthy infants have been born following immature oocyte retrieval and IVM.

In Vitro Maturation of Human Immature Oocytes in Culture Medium Supplemented with Patient's Own Serum or Donor Follicular Fluid

Abstract In this study, to avoid the virus contamination in the maturation medium by addition of donor follicular fluid (FF) from other in vitro fertilization (IVF) cycles, we examined the outcome of in vitro maturation (IVM) protocol using medium containing patient's own serum. Data were retrospectively collected from 68 irregularly cycling women (31 ± 3.6 years) who were diagnosed as having polycystic ovarian syndrome. Immature oocytes were retrieved transvaginally 36 h after an injection of 10,000 IU hCG. Immature oocytes were matured for 24–26 h in medium supplemented with 10% (v/v) heat-inactivated patient's own serum (group S) or with 20% (v/v) heat-inactivated FF from donors who had undergone IVF cycles (group FF). All mature oocytes were inseminated by intracytoplasmic sperm injection. There were no statistical differences in the rates of maturation (49.2% vs. 45.6%), fertilization (85.0% vs. 84.2%), and pregnancy (16.0% vs. 15.4%) between group S and group FF. The supplementation of patient's own...

Comparison of Basic Medium for the In Vitro Maturation for Human Immature Oocytes

Although in vitro maturation-in vitro fertilization (IVM-IVF) program has been successfully applied into human ART program for PCO patients, the pregnancy rate of this procedure is still low. This disadvantage is caused by poor maturation of human immature oocytes and no synchronization with implantation windows. So, one of the key points for successful IVM procedure is the establishment of optimal maturation medium for proper cytoplasmic maturation, fertilization and development. This study was performed to find a proper basic medium for better quality of oocytes and embryos by comparing two types of commercial IVF media.

Successful healthy birth in vitro maturation of human immature oocytes · Attempt of the unstimulated menstrual cycles and Frozen-Thawed embryo cycles

Objective: The IVM of human oocytes retrieved during unstimulated cycles is a reproductive technology of increasing interest. This study was examined about IVM in the unstimulated menstrual cycles (Fresh cycle) and frozen-thawed embryo transfer in hormone replacement cycles (Frozen cycle).Design: A retorospective randomized studyMaterials/Methods: Immature oocytes were retrieved transvaginally between days 8–23 of unstimulated menstrual cycles from women. Oocytes were cultured in TCM199 medium containing 20% heat-inactivated Follicular fluid, 10IU/ml FSH, 20IU/ml hCG, 10ng/ml Estradiol for 24 hours at 37°C and under 5% CO2, 5% O2, 90% N2 humidified atmosphere. All oocytes matured in metaphase2 were injected with husband sperm, and then cultured in fertilization medium for the first 16–18 hours. Fertilized embryos were changed medium to cleavage medium for 3 days until embryo transfer in Fresh cycle. In Frozen cycle, Zygotes on day 1 after ICSI were frozen, and then the thawed embryos were transferred at 2–8 cells stage with hormone replacement.Results: 19 cycles in Fresh cycle and 9 cycles in Frozen cycle from our program were treatment this study. The mean of oocytes aspirated per patients was 8.9 ± 5.9. After 24 hours of maturation 51.8% (88/170) of oocytes had a visible first polar body. After insemination, 78.4% (69/88) of the oocytes were fertilized and cleavage rate were 97.4% (37/38). The embryos were cultured for 3 days after insemination. Frozen-thawed embryos, 78.6% (22/28) were recovered and cleavage rate were 100% (22/22). The average of embryo transfer was 2.8 ± 1.5 in Fresh cycle, 2.4 ± 1.0 in Frozen cycle. The clinical pregnancy rate of Fresh cycle and Frozen cycle was 23.1% (3/13) and 22.2% (2/9). The implantation rate was 8.1% (3/37) and 13.6% (3/22). One patient delivered a healthy singleton in Fresh cycle and healthy twins in Frozen cycle.Conclusions: This study demonstrates that human immature oocytes retrieved from women with unstimulated menstrual cycles can undergo maturation, fertilization, pregnancy, and that the resulting embryo can establish healthy birth. The hormone replacement cycle is a good method. This method can solve synchronization to embryo and endometrium. Pregnancy rate is never high, but it is big progress for the PCO patients. We confirm that further studies are good oocyte retrieval timing, IVM medium of high maturation rate and synchronization method.Supported by: None. Objective: The IVM of human oocytes retrieved during unstimulated cycles is a reproductive technology of increasing interest. This study was examined about IVM in the unstimulated menstrual cycles (Fresh cycle) and frozen-thawed embryo transfer in hormone replacement cycles (Frozen cycle). Design: A retorospective randomized study Materials/Methods: Immature oocytes were retrieved transvaginally between days 8–23 of unstimulated menstrual cycles from women. Oocytes were cultured in TCM199 medium containing 20% heat-inactivated Follicular fluid, 10IU/ml FSH, 20IU/ml hCG, 10ng/ml Estradiol for 24 hours at 37°C and under 5% CO2, 5% O2, 90% N2 humidified atmosphere. All oocytes matured in metaphase2 were injected with husband sperm, and then cultured in fertilization medium for the first 16–18 hours. Fertilized embryos were changed medium to cleavage medium for 3 days until embryo transfer in Fresh cycle. In Frozen cycle, Zygotes on day 1 after ICSI were frozen, and then the thawed embryos were transferred at 2–8 cells stage with hormone replacement. Results: 19 cycles in Fresh cycle and 9 cycles in Frozen cycle from our program were treatment this study. The mean of oocytes aspirated per patients was 8.9 ± 5.9. After 24 hours of maturation 51.8% (88/170) of oocytes had a visible first polar body. After insemination, 78.4% (69/88) of the oocytes were fertilized and cleavage rate were 97.4% (37/38). The embryos were cultured for 3 days after insemination. Frozen-thawed embryos, 78.6% (22/28) were recovered and cleavage rate were 100% (22/22). The average of embryo transfer was 2.8 ± 1.5 in Fresh cycle, 2.4 ± 1.0 in Frozen cycle. The clinical pregnancy rate of Fresh cycle and Frozen cycle was 23.1% (3/13) and 22.2% (2/9). The implantation rate was 8.1% (3/37) and 13.6% (3/22). One patient delivered a healthy singleton in Fresh cycle and healthy twins in Frozen cycle. Conclusions: This study demonstrates that human immature oocytes retrieved from women with unstimulated menstrual cycles can undergo maturation, fertilization, pregnancy, and that the resulting embryo can establish healthy birth. The hormone replacement cycle is a good method. This method can solve synchronization to embryo and endometrium. Pregnancy rate is never high, but it is big progress for the PCO patients. We confirm that further studies are good oocyte retrieval timing, IVM medium of high maturation rate and synchronization method. Supported by: None.

Maternal serum supplementation in culture medium benefits maturation of immature human oocytes

This study compared the rates of maturation, fertilization, cleavage and pregnancy among oocytes matured in medium containing either human serum albumin (HSA) or maternal serum. Immature oocytes were obtained from 51 consecutive regularly cycling women <38 years of age. Immature oocytes were aspirated transvaginally on cycle day 8–9 after priming with FSH (Gonal-F 150 IU/day for 3 days, initiated on day 3). Oocytes were matured in Dyrkningsmedie til IVM supplemented with recombinant FSH (rFSH) 0.075 IU/ml and HCG 0.5 IU/ml for 28–30 h. In group I ( n = 63 oocytes obtained from the first 23 cycles) the culture medium was supplemented with 2% (w/v) HSA. In group II ( n = 74 oocytes obtained from the following 28 cycles) the medium was supplemented with 10% (v/v) heat-inactivated maternal serum. Intracytoplasmic sperm injection (ICSI) was performed on all methaphase II oocytes. Significantly increased rates of maturation 47/74 (63%) vs. 26/63 (41%) ( P < 0.05), pregnancy 6/28 (21%) vs. 0/23 (0%) ( P < 0.05) and implantation 6/20 (30%) vs. 0/15 (0%) ( P < 0.05) were obtained from oocytes matured in culture medium with maternal serum supplementation compared with oocytes matured in medium supplemented with HSA. These results indicate that factors other than albumin in maternal serum play an important role in maturation and subsequent developmental capacity of human oocytes.

Effects of ovarian source, patient age, and menstrual cycle phase on in vitro maturation of immature human oocytes

Objective: To determine the efficiency of in vitro maturation, expressed by nuclear maturation, of oocytes aspirated during gynecologic surgeries or collected from excised ovaries. To assess the effect of patient age and cycle phase at collection on the oocyte’s ability to mature in vitro. To examine the time course of oocyte maturation in vitro. Design: Nuclear maturation based on patient criteria compared. Setting: University-based IVF program and research center. Patient(s): Consented patients undergoing gynecologic surgeries or patients undergoing oophorectomy. Intervention(s): Oocytes were maintained in culture for 48 hours and evaluated for maturation. Main Outcome Measure(s): Nuclear maturation evaluated as germinal vesicle breakdown (GVBD) or progression to the metaphase II (MII) stage. Result(s): A significantly higher percentage of oocytes collected during the follicular phase of the menstrual cycle underwent GVBD than did oocytes collected during the luteal phase (60% versus 48%, respectively). The percentage of oocytes reaching the MII stage, from these two groups, was not different. No statistically significant differences in maturation were observed in oocytes from different ovarian sources or from patients >40 or <40 years of age. Conclusion(s): These data suggest that oocytes collected during the follicular phase are more likely to undergo GVBD than oocytes collected during the luteal phase. In this study, ovarian source, age, or cycle phase did not influence the final meiotic maturation of oocytes to metaphase II.