Comparison of luteal phase and follicular phase in-vitro maturation in women with oocyte maturation abnormalities

RESEARCH QUESTION

Are there differences in immature oocyte retrieval following luteal phase in-vitro maturation (IVM) compared with follicular phase IVM in women with oocyte maturation abnormalities (OMAs).

DESIGN

From January 2019 to May 2023, a retrospective cohort study at a private IVF centre included 36 women with 53 IVM cycles in Group 1 (follicular phase) and 24 women with 32 IVM cycles in Group 2 (luteal phase). Additionally, nine women had both follicular and luteal phase IVM cycles for intracycle variability analysis.

RESULTS

There were no differences in oocyte maturation stages between the groups at collection. Group 1 and Group 2 exhibited comparable median metaphase II oocyte rates per patient at 48 h after collection [40.0%, interquartile range (IQR) 0.0-66.7% versus 22.5%, IQR 0.0-52.9%] (P = 0.53). The median fertilization rate in Group 1 (66.7%, IQR 50.0-66.7%) was found to be comparable with that in Group 2 (66.7%, IQR 50.0-66.7%). There were no significant differences in the yielded embryo grades and pregnancy rates between the groups. Comparing follicular and luteal phase IVM within the same menstrual cycle in nine patients, no differences were observed in metaphase II oocyte maturation rates (P > 0.05).

CONCLUSIONS

This study found no significant differences in oocyte maturation, fertilization rate, embryo quality or pregnancy outcomes between luteal phase and follicular phase IVM in women with OMAs. These findings suggest that luteal phase IVM can be used similarly to follicular phase IVM, offering a potential avenue to enhance embryo yield for women with OMAs.

Oocyte in-vitro maturation primed with letrozole-HCG versus FSH-HCG in women with oocyte maturation abnormalities: a retrospective study

RESEARCH QUESTION

Are there differences between in-vitro maturation (IVM) primed with letrozole-human chorionic gonadotrophin (HCG) and IVM primed with FSH-HCG in women with oocyte maturation abnormalities (OMAs), defined as at least two failed IVF cycles where immature oocytes were retrieved?

DESIGN

This retrospective study was conducted at a private fertility clinic from January 2009 to April 2023. The final analysis included 75 women in Group 1 (IVM primed with FSH-HCG) and 52 women in Group 2 (IVM primed with letrozole-HCG).

RESULTS

A significantly higher median number of oocytes was obtained in Group 1 compared with Group 2 {9 [interquartile range (IQR) 1-5] versus 5 (IQR 1-18); P < 0.001}. However, no differences in oocyte maturation stage at collection were found between the groups (P > 0.05). At the end of IVM, Group 1 had 73/666 mature oocytes and Group 2 had 106/322 mature oocytes, and the median metaphase II oocyte rate per patient was higher in Group 2 [33.3% (IQR 66.7-100.0%) versus 0.0% (IQR 0.0-22.2%); P < 0.001]. Moreover, Group 2 demonstrated a higher median fertilization rate [66.7% (IQR 50.0-100.0%) versus 50.0% (IQR 0.0-66.7%); P = 0.027]. Group 2 had a higher proportion of Grade 2 embryos (58.5% versus 6.3%), and Group 1 had a higher proportion of Grade 3 embryos (93.8% vs 24.4%; P < 0.001). Notably, all pregnancies obtained in the study were in Group 2 (5 versus 0; P = 0.042).

CONCLUSIONS

IVM primed with letrozole-HCG in women with prior failed IVF cycles due to OMAs may result in mature oocytes, clinical pregnancies and live births. The effectiveness of letrozole priming for the subtypes of OMAs needs further investigation, with studies including greater numbers of cases.

Transcriptomic integrity of human oocytes used in ARTs: technical and intrinsic factor effects

BACKGROUND

Millions of children have been born throughout the world thanks to ARTs, the harmlessness of which has not yet been fully demonstrated. For years, efforts to evaluate the specific effects of ART have focused on the embryo; however, it is the oocyte quality that mainly dictates first and foremost the developmental potential of the future embryo. Ovarian stimulation, cryopreservation, and IVM are sometimes necessary steps to obtain a mature oocyte, but they could alter the appropriate expression of the oocyte genome. Additionally, it is likely that female infertility, environmental factors, and lifestyle have a significant influence on oocyte transcriptomic quality, which may interfere with the outcome of an ART attempt.

OBJECTIVE AND RATIONALE

The objective of this review is to identify transcriptomic changes in the human oocyte caused by interventions specific to ART but also intrinsic factors such as age, reproductive health issues, and lifestyle. We also provide recommendations for future good practices to be conducted when attempting ART.

SEARCH METHODS

An in-depth literature search was performed on PubMed to identify studies assessing the human oocyte transcriptome following ART interventions, or in the context of maternal aging, suboptimal lifestyle, or reproductive health issues.

OUTCOMES

ART success is susceptible to external factors, maternal aging, lifestyle factors (smoking, BMI), and infertility due to endometriosis or polycystic ovary syndrome. Indeed, all of these are likely to increase oxidative stress and alter mitochondrial processes in the foreground. Concerning ART techniques themselves, there is evidence that different ovarian stimulation regimens shape the oocyte transcriptome. The perturbation of processes related to the mitochondrion, oxidative phosphorylation, and metabolism is observed with IVM. Cryopreservation might dysregulate genes belonging to transcriptional regulation, ubiquitination, cell cycle, and oocyte growth pathways. For other ART laboratory factors such as temperature, oxygen tension, air pollution, and light, the evidence remains scarce. Focusing on genes involved in chromatin-based processes such as DNA methylation, heterochromatin modulation, histone modification, and chromatin remodeling complexes, but also genomic imprinting, we observed systematic dysregulation of such genes either after ART intervention or lifestyle exposure, as well as due to internal factors such as maternal aging and reproductive diseases. Alteration in the expression of such epigenetic regulators may be a common mechanism linked to adverse oocyte environments, explaining global transcriptomic modifications.

WIDER IMPLICATIONS

Many IVF factors and additional external factors have the potential to impair oocyte transcriptomic integrity, which might not be innocuous for the developing embryo. Fortunately, it is likely that such dysregulations can be minimized by adapting ART protocols or reducing adverse exposure.

Follicular fluid C3a-peptide promotes oocyte maturation through F-actin aggregation

BACKGROUND

Immature cumulus-oocyte complexes are retrieved to obtain mature oocytes by in vitro maturation (IVM), a laboratory tool in reproductive medicine to obtain mature oocytes. Unfortunately, the efficiency of IVM is not satisfactory. To circumvent this problem, we therefore intended to commence with the composition of ovarian follicular fluid (FF), an important microenvironment influencing oocyte growth. It is well known that FF has a critical role in oocyte development and maturation. However, the components in human FF remain largely unknown, particularly with regard to small molecular peptides.

RESULTS

In current study, the follicular fluid derived from human mature and immature follicles were harvested. The peptide profiles of FF were further investigated by using combined ultrafiltration and LC-MS/MS. The differential peptides were preliminary determined by performing differentially expressed analysis. Human and mouse oocyte culture were used to verify the influence of differential peptides on oocyte development. Constructing plasmids, cell transfecting, Co-IP, PLA etc. were used to reveal the detail molecular mechanism. The results from differentially expressed peptide as well as cultured human and mouse oocytes analyses showed that highly conserved C3a-peptide, a cleavage product of complement C3a, definitely affected oocytes development. Intriguingly, C3a-peptide possessed a novel function that promoted F-actin aggregation and spindle migration, raised the percentage of oocytes at the MII stage, without increasing the chromosome aneuploidy ratio, especially in poor-quality oocytes. These effects of C3a-peptide were attenuated by C3aR morpholino inhibition, suggesting that C3a-peptide affected oocytes development by collaborating with its classical receptor, C3aR. Specially, we found that C3aR co-localized to the spindle with β-tubulin to recruit F-actin toward the spindle and subcortical region of the oocytes through specific binding to MYO10, a key regulator for actin organization, spindle morphogenesis and positioning in oocytes.

CONCLUSIONS

Our results provide a new perspective for improving IVM culture systems by applying FF components and also provide molecular insights into the physiological function of C3a-peptide, its interaction with C3aR, and their roles in enabling meiotic division of oocytes.

In vitro maturation (IVM) of human immature oocytes: is it still relevant?

In vitro maturation (IVM) of human immature oocytes has been shown to be a viable option for patients at risk of ovarian hyperstimulation syndrome (OHSS), those seeking urgent fertility preservation and in circumstances where controlled ovarian stimulation is not feasible. Moreover, IVM techniques can be combined with ovarian tissue cryobanking to increase the chances of conception in cancer survivors. The clinical applications of IVM in the field of reproductive medicine are rapidly expanding and the technique is now classified as non-experimental. In contrast to conventional IVF (in vitro fertilization), IVM offers several advantages, such as reduced gonadotropin stimulation, minimal risk of ovarian hyperstimulation syndrome (OHSS), reduced treatment times and lower costs. However, the technical expertise involved in performing IVM and its lower success rates compared to traditional IVF cycles, still pose significant challenges. Despite recent advances, such as innovative biphasic IVM systems, IVM is still an evolving technique and research is ongoing to refine protocols and identify techniques to improve its efficiency and effectiveness. A comprehensive understanding of the distinct mechanisms of oocyte maturation is crucial for obtaining more viable oocytes through in vitro methods, which will in turn lead to significantly improved success rates. In this review, the present state of human IVM programs and future research directions will be discussed, aiming to promote a better understanding of IVM and identify potential strategies to improve the overall efficiency and success rates of IVM programs, which will in turn lead to better clinical outcomes.

TUBB8 mutations as a cause of oocyte maturation abnormalities: presentation of oocyte and embryo profiles and novel mutations

RESEARCH QUESTION

What are the embryonic profiles and oocyte maturation dynamics in patients with tubulin beta eight class VIII (TUBB8) mutations leading to oocyte maturation abnormalities (OMAS), and are pregnancies possible in this population?

DESIGN

A prospective cohort study was undertaken in a private fertility clinic between January 2019 and December 2022. Whole-exome genomic studies (WES) were performed to detect mutation types. In-vitro maturation (IVM) was compared in 18 subjects: nine with TUBB8 mutations, and nine without TUBB8 mutations to act as the control group. The distributions of oocyte maturation and embryonic development profiles were recorded. IVF and IVM outcomes of the 18 cases were evaluated. The primary outcomes were the embryonic profiles and maturation dynamics of oocytes derived from IVF or IVM in women as related to TUBB8 mutations.

RESULTS

Mutations were detected in 52 of 89 (58.4%) women who underwent WES analysis. Twelve TUBB8 mutations were detected in nine women (10.1%) with OMAS. Seven novel TUBB8 mutations were noted. Two pregnancies were obtained in women with c.535 G>A TUBB8 mutations. When comparing IVM outcomes between women with and without TUBB8 mutations, there were no differences in oocyte, embryo or pregnancy parameters (P>0.05 in all cases).

CONCLUSIONS

It is clear that further TUBB8 mutations which cause oocyte or embryonic arrest will be detected in future. Although biochemical or ectopic pregnancies may be possible in some of these women, no live births or ongoing pregnancies have been reported to date.

Outcomes of the Next In Vitro Fertilization Cycle in Women with Polycystic Ovary Syndrome after a Failed In Vitro Maturation Attempt

BACKGROUND

In vitro maturation (IVM) is indicated in women with polycystic ovary syndrome (PCOS) who have a very good ovarian response during in vitro fertilization (IVF) and are therefore at high risk of ovarian hyperstimulation syndrome (OHSS). According to the latest practice committee document, IVM could be a major advance in assisted reproductive technology (ART) procedures (reduced cost and simplified treatment); nevertheless, retrospective studies of IVM versus IVF still demonstrate lower chances of a live birth with IVM. Could IVM prove to be an optimal first-line treatment approach? And limited information is available concerning the success of the subsequent IVF cycle after the failure of an IVM cycle. Does IVM treatment adversely affect the subsequent IVF cycle, and is this worth considering before performing the IVF cycle for women with PCOS?

METHODS

This prospective nested case-control study at the Peking University Reproductive Medicine center in China was performed between March 2018 and September 2020. Women aged 20-38 years with PCOS and infertility and who were scheduled for their first IVF attempt were eligible. A total of 351 women were randomly allocated to receive one cycle of unstimulated natural IVM (n = 175) or one cycle of standard IVF with a flexible GnRH antagonist protocol followed by hCG as an ovulation trigger (n = 176). This study involved 234 women (58 women with no blastocysts in the first IVM cycle and 158 women who underwent the first IVF cycle). Cumulative live birth rate at 12 months after oocyte retrieval and OHSS of a standard controlled ovarian stimulation (COS) IVF cycle were compared between 58 women in an IVF cycle following a failed IVM cycle and 158 women who underwent the first IVF cycle.

RESULTS

No significant differences were found in the cumulative live birth rate (CLBR), ongoing pregnancy rate, or clinical pregnancy rate at 12 months after oocyte retrieval between the two groups (56.9% vs. 58.9%, p = 0.795; 58.6% vs. 60.8%, p = 0.776; and 84.5% vs. 76.0%, p = 0.178). The incidence of moderate-to-severe OHSS was not significantly different between the groups (6.9% vs. 5.7%, p = 0.742). Additionally, there were no significant differences in the total gonadotropin dose, stimulation duration, number of retrieved oocytes, number of retrieved mature oocytes, or fertilization rates.

CONCLUSIONS

Even if the first IVM attempt failed in subfertile women with PCOS, comparable cumulative live birth rates were observed in the subsequent IVF cycle. IVM treatment does not adversely affect the subsequent IVF cycle.

Alternatives to in vitro fertilization

There have been concerns on the potential overuse of in vitro fertilization (IVF) in view of the lack of evidence on effectiveness in certain populations, potential short and long-term safety risks, and economic considerations. On the other hand, the use of alternatives to IVF seems to be underappreciated in clinical practice as well as research. In this review, we summarized the up-to-date evidence on the effectiveness, safety as well as cost-effectiveness of different alternatives to IVF, including expectant management, intrauterine insemination, tubal flushing, in vitro maturation as well as intravaginal culture. We also discussed the trend of IVF use over the last decade and the available tiers of service because of intravaginal culture, and revisited the roles of different alternatives to IVF in modern reproductive medicine from both clinical and research perspectives.

Regulation of proteolysis in bovine cumulus cells with possible inclusion of proton pump activators

PURPOSE

To reveal the effects of V-ATPase proton pump activation on lysosomal acidity and protein degradation in cultured cumulus cells.

METHODS

Cumulus cells from bovine ovaries were cultured in the presence of 10 and 50 μM doses of V-ATPase proton pump activators PIP2, PMA, and DOG for 12 and 24 hours. At the end of the culture period, the level of protein degradation was evaluated through DQ-Red-BSA analysis and the lysosomes were detected through a fluorescent probe. In addition, total and phosphorylated MAPK1/3 and AKT protein levels of cumulus cells were determined through western blotting.

RESULTS

PIP2 and PMA were shown to increase protein degradation and lysosomal acidity in cultured bovine cumulus cells, whereas DOG did not have any significant effects on these cells. Total and phosphorylated MAPK and AKT protein levels were higher in PIP2 and PMA groups compared to the control and DOG.

CONCLUSION

Particular proton pump activators can enhance protein degradation and lysosomal acidification in cultured bovine cumulus cells without having detrimental effects on cell signaling members required for cell viability and proper functioning. Due to the cellular interactions, increasing the lysosomal activity in cumulus cells in the culture environment could also affect the removal of protein aggregates in the oocytes. This strategy could be effective for improving in vitro maturation of the oocytes by providing proteostasis.

High efficiency of homemade culture medium supplemented with GDF9-β in human oocytes for rescue in vitro maturation

Objective

Optimizing culture media for the incubation of immature oocytes is a vital strategy to increase the oocyte maturation rate during in vitro maturation (IVM) programs. This study evaluated the IVM and fertilization rates of human germinal vesicle (GV) and metaphase I (MI) oocytes using two different maturation media (commercial and homemade) with or without growth differentiation factor 9-β (GDF9-β). supplementation.

Methods

Immature oocytes from intracytoplasmic sperm injection (ICSI) cycles were collected and assigned to one of two IVM culture media (commercial or homemade; cleavage-stage base). After maturation, MII oocytes were examined under an inverted microscope for the presence of the polar body, zona pellucida (ZP) birefringence, and meiotic spindle (MS) visualization after maturation in four conditions (commercial or homemade medium, with or without GDF9-β. ICSI was done for matured oocytes, and fertilization was confirmed by the visualization of two distinct pronuclei and two polar bodies.

Results

No significant differences were found between the two culture media in terms of the time and rate of oocyte maturation or the rate of fertilization (p>0.05). Growth factor supplementation increased the 24-hour maturation rate for both GV and MI oocytes only in homemade medium. The maturation rate after 24 hours was higher for MI oocytes (p<0.05). Similar results were observed for MS visualization and ZP structure in both types of media (p>0.05).

Conclusion

Higher rates of oocyte maturation and fertilization were observed after application of homemade medium supplemented with GDF9-β. Therefore, this combination may be recommended as an alternative for clinical IVM programs.

Present state and future outlook for the application of in vitro oocyte maturation (IVM) in human infertility treatment

In vitro oocyte maturation (IVM) is an assisted reproductive technology in which a meiotically immature oocyte (prophase I or germinal vesicle stage) is recovered from an antral follicle and matured in vitro prior to fertilization. This technology, although in widespread use in domestic livestock, is not typically implemented during human IVF cycles. This review examines how IVM is currently used in the clinical setting, including the various ways IVM is defined in practice. The role of IVM in patient care, and the major challenges for implementation are described. Efficiency and safety are critically explored. The role of IVM in oncofertility will also be discussed. Finally, the outlook for the future of clinical IVM is considered.

Perspectives on the development and future of oocyte IVM in clinical practice

Oocyte in vitro maturation (IVM) is an assisted reproductive technology designed to obtain mature oocytes following culture of immature cumulus–oocyte complexes collected from antral follicles. Although IVM has been practiced for decades and is no longer considered experimental, the uptake of IVM in clinical practice is currently limited. The purpose of this review is to ensure reproductive medicine professionals understand the appropriate use of IVM drawn from the best available evidence supporting its clinical potential and safety in selected patient groups. This group of scientists and fertility specialists, with expertise in IVM in the ART laboratory and/or clinic, explore here the development of IVM towards acquisition of a non-experimental status and, in addition, critically appraise the current and future role of IVM in human ART.

The impact of timing for estrogen supplementation in polycystic ovary syndrome patients undergoing primed in vitro maturation

OBJECTIVE

This study aims to determine the effects of early and late onset estrogen supplementation on the immature oocyte retrieval, fertilization and clinical pregnancy rates in follicle stimulating hormone (FSH) and human chorionic hormone (hCG) primed in vitro maturation (IVM) cycles of the patients with polycystic ovary syndrome (PCOS).

METHODS

This is a retrospective analysis of 161 patients with PCOS who underwent FSH and hCG primed IVM. Group 1 included 120 patients who received early onset estrogen supplementation while group 2 consisted of 41 patients who had late onset estrogen supplementation in primed IVM cycles. Immature oocyte (germinal vesicle and/or metaphase I) retrieval and fertilization rates were the primary outcomes, whereas clinical pregnancy and live rates were the secondary outcomes.

RESULTS

Group 1 patients had significantly higher body mass index and more previous IVF attempts (p = 0.001 and p = 0.008, respectively). All of the retrieved oocytes from the PCOS patients were either germinal vesicle or metaphase I oocytes and there were no metaphase II oocytes among the retrieved oocytes. Both groups had statistically similar numbers of metaphase I and fertilized oocytes (p > 0.05 for both). However, group 1 patients had significantly lower number of germinal vesicle oocytes but significantly higher number of metaphase II oocytes (p = 0.001 for both). Both groups had statistically similar fertilization (85.0% vs 78.0%), clinical pregnancy (49.2% vs 43.9%) and live birth (37.5% vs 39.0%) rates (p > 0.05 for all).

CONCLUSION

Early onset estrogen supplementation appears to improve the quality of retrieved immature oocytes and contribute to the maturation of oocytes in stimulated IVM cycles.

Lysophosphatidic acid improves oocyte quality during IVM by activating the ERK1/2 pathway in cumulus cells and oocytes

Oocyte IVM technology is an option for fertility preservation in some groups of patients, such as those with polycystic ovary syndrome, patients with ovarian hyperstimulation syndrome, and for patients with cancer. However, the developmental potential of oocytes from IVM still needs to improve. Several previous studies have reported that lysophosphatidic acid (LPA) promotes glucose metabolism, cumulus cell (CC) expansion, and oocyte nuclear maturation. However, the effect of LPA on oocyte cytoplasmic maturation, particularly mitochondrial function, has rarely been studied and the underlying mechanism is largely unknown, which impedes (pre)clinical applications of LPA. In this study, cumulus-oocyte complexes (COCs) and cumulus-denuded germinal vesicle oocytes (DOs) were treated with various concentrations of LPA during IVM, in the presence or absence of the oxidative stressor cyclophosphamide (CTX). In both normal and CTX-damaged COCs, the 25 μM LPA group exhibited improved CC expansion capacity, a higher nuclear maturation rate, and superior mitochondrial function, compared to no LPA treatment. When the concentration of LPA was over 40 μM, detrimental effects of LPA on oocyte maturation occurred. Compared with COCs, the addition of LPA slightly improved oocyte nuclear and cytoplasmic maturation of DOs, but this was not statistically significant. We observed that LPA promotes the activation of extracellular signal-regulated kinase (ERK)1/2, although this was not statistically significant in DOs. Furthermore, LPA could not reverse the negative effect of CC expansion and mitochondrial function after inactivation of ERK1/2 by U0126. RNA-sequencing and RT-PCR results showed that LPA upregulated several ERK1/2 downstream genes related to CC expansion, such as Areg, Cited4, and Ptgs2. This study demonstrates that LPA improves oocyte quality during IVM through the activation of ERK1/2 pathway CCs and oocytes, which provides evidence for the potential addition of LPA to IVM medium.

Enhancing the scope of in vitro maturation for fertility preservation: transvaginal retrieval of immature oocytes during endoscopic gynaecological procedures

STUDY QUESTION

Could in vitro maturation (IVM) following transvaginal oocyte retrieval during gynaecological surgery (IVM-surgery) be an effective and safe strategy for fertility preservation?

SUMMARY ANSWER

IVM-surgery on unstimulated ovaries is a novel option that can be considered for fertility preservation for women requiring gynaecological surgery, but more research is needed to identify appropriate patients who may benefit and to determine the cost-effectiveness of such an approach.

WHAT IS KNOWN ALREADY

IVM followed by oocyte/embryo cryopreservation has been useful as a safe reproductive strategy for some infertile women.

STUDY DESIGN, SIZE, DURATION

This prospective cohort study comprised 158 consecutive women with polycystic ovary syndrome (PCOS) who underwent laparoscopy or hysteroscopy for other reasons and had concomitant transvaginal oocyte retrieval followed by IVM between 2014 and 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 158 women with anovulatory PCOS who underwent IVM-surgery in our infertility centre were recruited for this study. Matured IVM oocytes obtained from these women were either freshly fertilized and subsequently frozen at the blastocyst stage (fresh oocyte group, n = 46) or the oocytes were frozen (frozen oocyte group, n = 112) for fertility preservation followed by later thawing for insemination and cleavage embryo transfer (ET) (n = 33). The following outcomes were then evaluated: embryological data, clinical pregnancy rate, live birth rate (LBR), neonatal outcomes, post-operative complications and post-operative ovarian function.

MAIN RESULTS AND THE ROLE OF CHANCE

Among all the women who underwent IVM-surgery, the clinical pregnancy rate and LBR per initiated IVM cycle were 9.5% (15/158) and 6.9% (11/158), respectively. Women (40.6%, 20/33) who underwent the procedure with frozen-thawed oocytes (oocyte survival rate, 83.0%) obtained a high quality of cleaved embryos. In the fresh oocyte group, the clinical pregnancy rate and LBR per ET cycle were 69.2 and 53.8%, respectively. In the frozen oocyte group, the clinical pregnancy rate and LBR per ET cycle were 28.6 and 19.1%, respectively. No adverse neonatal outcomes were recorded. IVM-surgery was not associated with post-operative complications, a longer hospital stay, or impaired ovarian function.

LIMITATIONS, REASONS FOR CAUTION

Because of the small sample size and the low utilization rate and cost-effectiveness per retrieval, the present findings should be interpreted with caution, and further studies are needed for the long-term follow-up of live births.

WIDER IMPLICATIONS OF THE FINDINGS

This strategy can also help patients with normal ovulation to obtain available oocytes and embryos for cryopreservation and subsequent use.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by the Joint Research Fund for Overseas Natural Science of China (No. 31429004), the National Key Research and Development Program of China (No. 2017YFC1002000, 2017YFC1001504, 2016YFC1000302), the Ministry of Science and Technology of China Grants (No. 2014CB943203), the Chinese Society of Reproductive Medicine Fund (No. 16020400656) and the National Natural Science Foundation of China (No. 81300456). All the authors have nothing to disclose in terms of conflicts of interest.

TRIAL REGISTRATION NUMBER

chictr-ONC-17011861.

Supplementation of the In Vitro Maturation Culture Medium of Mouse Oocytes with Growth Hormone Improves Pregnancy Outcomes

This study aimed to examine the effects of adding growth hormone (GH) into the in vitro maturation (IVM) culture medium of mouse oocytes on pregnancy outcomes. Cumulus-oocyte complexes (COCs) were cultured in a medium with (GH group, 100 ng/mL) or without (Con group) GH. Thereafter, chromosome morphology, spindle morphology, and mitochondrial function were examined. Embryo development and blastocyst quality after in vitro fertilization were evaluated. After the embryo transfer, the implantation sites and pregnancy outcomes were evaluated. The oocyte maturation rate of the GH group (81.8 ± 9.6%) was compared to that of the Con group (81.3 ± 6.9%, P = 0.928). The proportion of morphologically abnormal spindles in GH-treated oocytes (7.1 ± 0.9%) was significantly lower than control oocytes (13.7 ± 1.3%, P = 0.032), whereas the proportion of morphologically abnormal chromosomes and mitochondrial distribution was similar between the groups. The mitochondrial membrane potential (P < 0.001) and ATP concentration (P < 0.001) in GH-exposed oocytes were higher than those in control oocytes. After fertilization, the blastocyst rate in the GH group (33.8 ± 13.2%) was significantly higher than the Con group (16.2 ± 2.0%, P = 0.003). In addition, inner cell mass (ICM) number (13.91 ± 3.48 vs. 7.00 ± 1.91, P < 0.001), total cell number (47.45 ± 8.39 vs. 37.71 ± 4.15, P = 0.007), and the ratio of ICM/total cell number (29.9 ± 8.2% vs. 18.6 ± 5.0%, P = 0.002) of blastocyst were all higher in GH group. The implantation rate (71.2 ± 1.9% vs. 39.4 ± 16.4%, P < 0.001) and litter size (8.50 ± 3.99 vs. 3.00 ± 1.22, P = 0.018) were significantly higher in the GH group. Although addition of GH into IVM culture medium does not improve oocyte maturation rate, it improves oocyte and embryo quality, which leads to better embryo development and pregnancy outcomes.

Comparison of three sperm selection methods for ICSI-DGC, Cumulus column, and incubation with supernatant product of adipose tissue-derived adult stem cells: An experimental study

Background

The examination of sperm parameters and sperm DNA integrity are necessary for male fertility expression. These parameters can be affected by method of sperm separation.

Objective

To measure the damage of each sperm separation method on the sperm parameters and sperm DNA integrity.

Materials and Methods

In this experimental study, semen samples of 20 infertile men with asthenoteratozoospermia (Infertility Research Center, Qom, Iran, 2017) were processed in three ways: density gradient centrifugation (DGC), cumulus column, and incubation with supernatant products of adipose tissue-derived adult stem cells (SPAS). The results of sperm parameters and DNA fragmentation before and after the process were statistically analyzed.

Results

The number of separated sperms by normal morphologies during the SPAS and the cumulus column was significantly more than the corresponding population in the DGC group. In addition, although all three methods have the same ability to increase total sperm motility and the number of recovered sperms, in the field of forwarding movement and DNA fragmentation, the SPAS method performed more efficiently (p = 0.021).

Conclusion

Sperm parameters and DNA fragmentation in the SPAS group were better than those in the DGC and cumulus column groups. Furthermore, it has been shown that the sperm capacity was increased with the SPAS method. However, the rearrangement of sperm chromatin by reducing the disulfide bridges and providing the possibility of re-histone over capacity causes a significant reduction in DNA fragmentation.

In vitro rescue immature oocytes - a literature review

Immature oocytes retrieved from in vitro fertilization (IVF) and clinical in vitro maturation (IVM) is a common problem, especially in patients with advanced age, poor ovarian response (POR), or polycystic ovary syndrome (PCOS). Considering there is no common name to describe this group of oocytes, we suggest naming all of immature oocytes retrieved from IVF and clinical IVM cycles as 'Medical Unusable Oocytes' (MUO) as none of them will be used for subsequent treatment and will eventually be discarded. Scientists attempt to improve the clinical utilization rate of MUO instead of discarding them. Rescue IVM and mitochondria supplementation may be available approaches to mature MUO. We propose a specific definition of rescue IVM, namely the cultivation and maturation of immature oocytes in vitro collected from IVF cycles with human chorionic gonadotropin (hCG) trigger. Rescue IVM is usually mixed up with clinical IVM. Clarification of the differences between rescue IVM and clinical IVM is necessary. This manuscript aims to clarify the rather confusing IVM procedures and review existing methods of improving rescue IVM, currently available information on the success rate, and explore the future possibility of rescue IVM serving as a promising tool in reproductive medicine.

Comparison of IVF and IVM outcomes in the same patient treated with a modified IVM protocol along with an oocytes-maturing system containing melatonin: A pilot study

AIM

To compare embryonic developmental competence and clinical outcomes of oocytes matured in vivo (IVF oocytes) and those matured in vitro (IVM oocytes) from the same IVM/IVF cycles, and to analyze the clinical efficiency of a melatonin-supplemented in vitro maturation system combined with a modified IVM/IVF protocol.

MAIN METHODS

We randomly recruited 22 patients undergoing IVM/IVF treatment protocol in our medical centre. The fertilization, cleavage and blastocyst formation rates, as well as clinical pregnancy, implantation and live birth/ongoing pregnancy rates were analysed and compared between IVF and IVM oocytes. We evaluated mitochondrial function indicators by fluorescence staining and confocal microscopy, including mitochondrial membrane potential, reactive oxygen species and calcium (Ca²⁺) levels in 15 IVF and 15 IVM oocytes.

KEY FINDINGS

There were no significant differences in fertilization or blastocyst formation rates between the IVF and IVM groups, whereas the cleavage rate was significantly higher in the IVF versus IVM group (100% vs 93.4 ± 10.9%, p = 0.03). There were no significant differences in the clinical pregnancy, implantation or live birth/ongoing pregnancy rates between the two groups. The cumulative clinical pregnancy and ongoing pregnancy/live birth rate per pick-up oocyte in the IVM/IVF treatment cycles were 68.2% (15/22) and 54.5% (12/22), respectively. The reactive oxygen species and Ca²⁺ levels were significantly increased, and mitochondrial membrane potential was significantly decreased, in IVM compared with IVF oocytes.

SIGNIFICANCE

The modified IVM/IVF protocol can be effectively applied to the treatment of some indicated patients and achieve ideal clinical outcomes, even though the developmental potential of IVM oocytes may not be as high as IVF oocytes.

In vitro maturation with letrozole priming: Can it be a solution for patients with cancerophobia? A pilot study

Objective:

To investigate whether letrozole priming could be used efficiently in patients undergoing in vitro maturation (IVM) as compared with follicle-stimulating hormone (FSH) priming.

Materials and Methods:

This is a retrospective analysis of 63 patients who underwent IVM due to the high risk of Ovarian Hyperstimulation syndrome (OHSS) (n=39), cancerophobia (n=16), and desire for IVM after failed in vitro fertilization attempts (n=8). Forty-two patients received FSH priming and 21 patients received letrozole priming.

Results:

The patients who had FSH or letrozole priming were statistically similar with respect to age, body mass index, duration of infertility, basal antral follicle count, serum anti-Müllerian hormone levels, and IVM indications (p>0.05 for all). When compared with the FSH priming group, the number of germinal vesicle oocytes, metaphase II and fertilized oocytes were significantly higher (p=0.003, p=0.001, and p=0.016, respectively), but the number of metaphase I oocytes was significantly lower in the letrozole priming group (p=0.002). The patients who received FSH and letrozole priming had statistically similar rates of implantation (33.3% vs 37.0%, p=0.709), clinical pregnancy (31.5% vs 33.3%, p=0.848), twinning (1.9% vs 3.7%, p=0.611), and live birth (24.1% vs 29.6%, p=0.682).

Conclusion:

Potential indications for IVM include patients with increased risk for OHSS and contraindication for hyperestrogenism. Aromatase inhibitors can be used to preserve the fertility of patients with estrogen-sensitive cancers. Letrozole priming appears to be an efficient approach in patients who undergo IVM, with likely less cost than FSH priming.

Can in vitro maturation overcome cycles with repeated oocyte maturation arrest? A classification system for maturation arrest and a cohort study

OBJECTIVE

To investigate the role of gonadotropin-stimulated and human chorionic gonadotropin (hCG) -primed in vitro oocyte maturation (IVM) in cases of repeated in vitro fertilization (IVF) failure due to various forms of oocyte maturation arrest (OMA).

METHODS

Retrospective cohort study.

RESULTS

In all, 63 women with IVF failure due to OMA were evaluated in this study. According to the Hatirnaz & Dahan classification, 11 (17.5%) women were OMA type 1, 22 (34.9%) were OMA type 2, 0 were OMA type 3, 11 (17.5%) were OMA type 4, and 19 women were OMA type 5 (30.1%). Fewer oocytes were retrieved in the IVM than in the IVF cycles. No embryos were produced from oocytes collected in the IVM cycles of women with OMA types 1, 2, and 4. In the OMA type 5 group, 9 (47.4%) day 2 embryos and 6 (31.6%) day 3 embryos were obtained. The difference between the groups was statistically significant (P = 0.001, P = 0.002, respectively). Single day 3 embryo transfer was performed for the six patients with OMA type 5 but no clinical pregnancies occurred.

CONCLUSIONS

Follicle-stimulating hormone-stimulated and hCG-primed IVM does not improve oocyte maturation, developmental potential, or pregnancy rates of women with OMA. Future studies directed to re-establishing normal cytoskeletal architecture and machinery, and resumption of meiosis may be beneficial for obtaining mature oocytes.

Gonadotropin releasing hormone agonist triggering for in vitro maturation cycles

The objective was to evaluate the outcomes of in vitro maturation (IVM) cycles using gonadotropin releasing hormone agonist (GnRH-ag) triggering. A retrospective cohort of IVM cycles from January 2015 to December 2019 in a single university-affiliated centre was examined. Main outcome measures were: (i) IVM maturation rate; and (ii) IVM maturation result. Secondary outcome measures were: (i) metaphase II (MII) rate on the day of egg retrieval; (ii) final MII maturation rate; and (iii) pregnancy rates. A total of 98 IVM cycles were performed during the study period: 50 (51%) were triggered with GnRH-ag (17 received FSH priming and 33 did not) and 48 cycles (49%) were triggered by hCG (37 with FSH priming and 11 without). A significant (p = 0.01) difference was noticed in maturation rate on egg retrieval day, in favour of the GnRH-ag group, although not in the final maturation rate achieved. Pregnancy rates were comparable between treatment sub-groups. GnRH-ag triggering in IVM cycles is an optional triggering mode and can be considered an acceptable option, especially when fertility preservation is a concern. GnRH agonists resulted in higher maturation rate on day of oocyte retrieval, but no difference in the total maturation rate.

Thoughts on the popularity of ICSI

Purpose

Intracytoplasmic sperm injection (ICSI) is the most widely utilized assisted reproductive technique (ART) worldwide. In this feature, we review the early assisted fertilization attempts that eventually led to the development of ICSI, and discuss its current utilization in cases of male and non-male factor infertility.

Methods

We researched the literature related to the development, indications, and current use of ICSI, such as sperm structural abnormalities, male genetic indications, surgically retrieved sperm, high sperm chromatin fragmentation, oocyte dysmorphism, and preimplantation genetic testing (PGT). We also describe the potential future applications of ICSI.

Results

This review summarizes the early micromanipulation techniques that led to the inception of ICSI. We also explore its current indications, including non-male factor infertility, where its use is more controversial. Finally, we consider the benefits of future advancements in reproductive biology that may incorporate ICSI, such as in vitro spermatogenesis, neogametogenesis, and heritable genome editing.

Conclusion

The versatility, consistency, and reliability of ICSI have made it the most prevalently utilized ART procedure worldwide.

Association between mild stimulated IVF/M cycle and early embryo arrest in sub fertile women with/without PCOS

BACKGROUND

The in vitro maturation (IVM) technique has physical and financial benefits, but a lower efficiency and outcome that is still unclear whether it is related to polycystic ovary syndrome (PCOS) itself or the IVM procedure. In this study, we analyzed the clinical and laboratory outcomes of an optimized IVM protocol in patients with and without PCOS. We also discussed the possible reasons for early embryo arrest in the IVM cycle.

METHODS

This prospective study involved 58 PCOS patients and 56 non-PCOS patients who underwent mild stimulated IVF combined IVM (IVF/M) cycles. The clinical and laboratory outcomes were compared between the two groups. Also, metaphase II (MII) oocytes were obtained after IVM from the two groups, and in vivo MII oocytes randomly collected from IVF patients were examined for mitochondrial function using a laser scanning confocal microscope (LSCM). The aneuploidy rate for arrested cleavage embryos from IVM and IVF oocytes were screened using Next Generation Sequencing (NGS).

RESULTS

Mildly stimulated IVF/M resulted in cumulative clinical pregnancy and implantation rates (40.2, 28.7% in the PCOS group vs. 41.9, 36% in the non-PCOS group), respectively. The blastocyst formation rates were comparable (28% vs. 28.2%) in PCOS and non-PCOS groups, respectively. Using LSCM, there was a significant decrease in the mitochondrial membrane potential of IVM oocytes compared with the control IVF oocytes (P < 0.001), but no significant difference between the PCOS and non-PCOS groups. The NGS showed that the aneuploidy rates were comparable (75, 75, and 66.6%) in IVM-PCOS, IVM-non-PCOS, and control IVF arrested embryos, respectively.

CONCLUSIONS

The mildly stimulated IVF/M protocol produced acceptable clinical outcomes in PCOS and non-PCOS patients. IVM itself rather than the PCOS condition adversely affected the embryo development through its effect on mitochondrial function, which appeared to be a possible cause for the embryo arrest in the IVM cycles rather than chromosomal aneuploidy.

Improving the maturation rate of human oocytes collected ex vivo during the cryopreservation of ovarian tissue

PURPOSE

The aim of the present study was to improve the in vitro maturation (IVM) procedure using oocytes from surplus ovarian tissue after fertility preservation.

METHODS

Twenty-five patients aged 17-37 years were included in the study. Maturation was compared between oocytes collected in HEPES-buffered medium or saline, and we determined whether transport on ice prior to oocyte collection affected maturation. Two different IVM media were used that were supplemented with and without recombinant human midkine. Mature oocytes were assessed for aneuploidy using next-generation sequencing (NGS).

RESULTS

On average, 36 immature oocytes were collected from each patient (range 7-90, N = 895). Oocytes recovered from HEPES-buffered medium matured at a higher rate than oocytes recovered from saline (36% vs 26%, p < 0.01). Ovarian transportation on ice prior to the procedure negatively affected maturation compared with non-transported samples (42% vs 27%, p < 0.01). The addition of midkine improved maturation rate (34% vs 27%, p < 0.05). On average, 11 MII oocytes were obtained per patient (range 1-30). NGS of 53 MII oocytes and their first polar bodies indicated that 64% were euploid.

CONCLUSIONS

The study demonstrated unexpectedly high number of immature oocytes collected from surplus ovarian tissue without any stimulation. The overall MII rate was one in three, resulting in a total number of MII oocytes that was similar to the number obtained after ovarian stimulation. If these MII oocytes prove suitable for IVF, they will provide a substantial improvement in fertility preservation for patients and advance IVM as an interesting platform for further improvements in assisted reproduction.

Human Chorionic Gonadotropin Priming Does Not Improve Pregnancy Outcomes of PCOS-IVM Cycles

Background: Influence of pre-retrieval human chorionic gonadotropin (HCG) priming on outcomes of in vitro maturation (IVM) remains controversial. This study aimed to evaluate the effect of HCG priming before oocyte retrieval on clinical outcomes of IVM cycles in patients with polycystic ovarian syndrome (PCOS). Methods: This was a retrospective cohort study analyzing data from the first IVM cycles of unstimulated PCOS patients in a reproductive center of university affiliated hospital from January 2006 to December 2017. Patients received HCG injection before oocyte retrieval were assigned to HCG priming group and those without HCG administration were categorized as none HCG priming (Non-HCG) group. Main outcomes included oocyte maturation rate, number of embryos available, clinical pregnancy rate, and live birth rate. Candidate factors of clinical pregnancy rate was explored by univariate analysis and multivariate logistic regression analysis. Results: There were 324 patients meeting the inclusion and exclusion criteria. Among them, 129 women received HCG priming and 195 other did not. Women in HCG group had significantly lower basal FSH level (5.17 ± 1.63 vs. 5.80 ± 2.38) than Non-HCG group. Both FSH levels were <10 IU/L and the absolute difference was 0.63 IU/L. Other basic characteristics were similar between groups with or without HCG priming. Oocyte maturation rate was trend to be higher in HCG group (52.68 vs. 48.56%) but no statistical significance was found (P = 0.097). No significant difference in clinical pregnancy rate was found between HCG and Non-HCG groups (31.37 vs. 35.67%). Miscarriage rates (31.25 vs. 34.43%) and live birth rates were also similar between groups. HCG priming was not correlated with clinical pregnancy rate in both univariate analysis (P = 0.468) and multivariate logistic regression analysis (P = 0.538; OR = 1.212; 95%CI: 0.657-2.237). Conclusion: HCG priming before oocyte retrieval may not improve clinical outcomes of IVM in patients with PCOS.

MicroRNA-375 regulates oocyte in vitro maturation by targeting ADAMTS1 and PGR in bovine cumulus cells

MicroRNAs (miRNAs) have attracted increasing attention for their function in oocyte in vitro maturation (IVM). In this study, we aimed to explore the functional role and underlying mechanism of miR-375 in oocyte IVM. Cumulus-oocyte complexes (COCs) were cultured in standard cell culture conditions until they reach metaphase II (MII) stage. MiR-375 overexpression or knockdown was achieved by corresponding lentiviral transduction. Levels of miR-375, disintegrin and metalloproteinase with thrombospondin-like motifs 1 (ADAMTS1) mRNA and progesterone receptor (PGR) mRNA were detected by qRT-PCR. Western blotting was used to assess the expression of ADAMTS1 and PGR protein. The targeted interaction between miR-375 and ADAMTS1 or PGR was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our results demonstrate that miR-375 is downregulated, and ADAMTS1 and PGR are upregulated in cumulus cells during COC maturation. MiR-375 negatively regulates COC maturation. Moreover, ADAMTS1 and PGR are two targets of miR-375 in cumulus cells. ADAMTS1 or PGR knockdown represses COC maturation and miR-375 inhibits the expression levels of ADAMTS1 and PGR in cumulus cells. Additionally, miR-375 overexpression-mediated suppressive effect on COC maturation is abated by ADAMTS1 or PGR expression restoration. In conclusion, our study suggests that miR-375 represses oocyte IVM at least partially through targeting ADAMTS1 and PGR in cumulus cells, providing a novel insight for the involvement and underlying mechanism of miR-375 in oocyte IVM.

Natural-cycle in vitro fertilization (IVF) combined with in vitro maturation in infertile patients with polycystic ovarian syndrome (PCOS) requiring IVF

OBJECTIVE

In this study, we report an experience of 59 natural-cycle IVF combined with in vitro oocyte maturation (IVF/M) cycles in patients with PCOS requiring IVF recruited based on limitations to afford a conventional IVF treatment in a 9-years period. Results of IVF/M were compared with 164 cycles of IVF in PCOS patients.

MATERIAL AND METHODS

In IVF/M cycles only hCG priming was used before oocyte recovery, with in vitro maturation of immature oocytes in a commercial medium. In conventional IVF group, recombinant FSH (rFSH) and GnRH agonist/antagonist for ovarian stimulation were used. In both groups, fertilization was achieved by intracytoplasmic sperm injection (ICSI) of mature oocytes and fresh embryos transferred at day 2 or day 3.

RESULTS

In all IVF/M cycles oocytes and transferable quality embryos were obtained, only in 6 IVF/M cycles mature oocytes were obtained at oocyte capture day. Clinical pregnancy rate per cycle was 39.0% vs 53.6% (p = 0.0682) and delivery rate per cycle was 30.5% vs 42.6% (p = 0.1209) in IVF/M and conventional IVF respectively. Patients with ovarian hyperstimulation syndrome (OHSS) were 0% in IVF/M vs 6.7% in conventional IVF (p = 0.0399).

CONCLUSION

Our experience in a private clinic in Mexico suggests that IVF/M can be a useful initial strategy to treat PCOS patients requiring IVF with comparable delivery rates to conventional IVF and a decreased risk of ovary hyperstimulation. IVF/M may be indicated to patients with limited resources paying without insurance for their infertility treatment.

Vaginal ultrasound-guided ovarian needle puncture compared to laparoscopic ovarian drilling in women with polycystic ovary syndrome

STUDY OBJECTIVE

To compare pregnancy outcomes in PCOS women undergoing transvaginal ovarian injury (TVOI) and laparoscopic ovarian drilling (LOD) DESIGN: 126 infertile patients with PCOS were included in this prospective cohort study CANADIAN TASK FORCE CLASSIFICATION OF LEVEL OF EVIDENCE: IIA.

SETTING

University-affiliated fertility center.

PATIENTS

Sixty-seven infertile patients with the history of failed in vitro maturation underwent follow-up as the TVOI group. Fifty-nine infertile women who underwent LOD acted as controls. All subjects had PCOS with menstrual irregularity and were anovulatory by repetitive serum progesterone levels.

INTERVENTIONS

The LOD group underwent six cauterizations of a single ovary with 30W for 4-6 s. Failed IVM subjects with 20-30 needle punctures per ovary acted as the TVOI group. Subjects were followed for six months.

MEASUREMENTS AND MAIN RESULTS

There was not a significant difference between the groups when the cases were evaluated in terms of spontaneous pregnancy or miscarriage rates. BMI levels decreased in both the TVOI and the LOD groups in a similar fashion. However, serum AMH and AFC decreased greater after LOD than they did with TVOI over the six-month duration of the study (p < 0.001 in both cases).

CONCLUSIONS

Preliminary data suggest that TVOI likely represents a safer, less costly and equally effective manner of surgical ovulation induction in anovulatory PCOS women when compared to LOD.

Immature Oocyte for Fertility Preservation

In vitro maturation (IVM) of human immature oocytes has been offered to women who are at risk of developing ovarian hyperstimulation syndrome (OHSS) caused by gonadotropin stimulation, such as PCO(S) patients or who have poor ovarian reserve. Cryopreservation of oocytes matured in vivo obtained in IVF cycles has improved after implementing the vitrification method and many successful results have been reported. Now, this procedure can be successfully offered to fertility preservation programs for patients who are in danger of losing their ovarian function due to medical or social reasons, and to oocyte donation programs. This vitrification technique has also been applied to cryopreserve oocytes obtained from IVM program. Some advantages of oocytes vitrification related with IVM are: (1) eliminating costly drugs and frequent monitoring; (2) completing treatment within 2 to 10 days (3) avoiding the use of hormones in cancer patients with hormone-sensitive tumors; and (4) retrieving oocytes at any point in menstrual cycle, even in the luteal phase. In addition, immature oocytes can also be collected from extracorporeal ovarian biopsy specimens or ovaries during caesarian section. Theoretically, there are two possible approaches for preserving immature oocytes: oocyte cryopreservation at the mature stage (after IVM) and oocyte cryopreservation at the Germinal Vesicle (GV)-stage (before IVM). Both vitrification of immature oocyte before/after IVM is not currently satisfactory. Nevertheless, many IVF centers worldwide are doing IVM oocyte cryopreservation as one of the options to preserve fertility for female cancer. Therefore, more studies are urgently required to improve IVM- and vitrification method to successfully preserve oocytes collected from cancer patients. In this review, present oocyte maturation mechanisms and recent progress of human IVM cycles will be discussed first, followed by some studies of the vitrification of human IVM oocyte.

In vitro maturation in subfertile women with polycystic ovarian syndrome undergoing assisted reproduction

BACKGROUND

Polycystic ovarian syndrome (PCOS) occurs in 4% to 7% of all women of reproductive age and 50% of women presenting with subfertility. Subfertility affects 15% to 20% of couples trying to conceive. A significant proportion of these women ultimately need assisted reproductive technology (ART). In vitro fertilisation (IVF) is one of the assisted reproduction techniques employed to raise the chances of achieving a pregnancy. For the standard IVF technique, stimulating follicle development and growth before oocyte retrieval is essential, for which a large number of different methods combining gonadotrophins with a gonadotrophin-releasing hormone (GnRH) agonist or antagonist are used. In women with PCOS, the supra-physiological doses of gonadotrophins used for controlled ovarian hyperstimulation (COH) often result in an exaggerated ovarian response, characterised by the development of a large cohort of follicles of uneven quality, retrieval of immature oocytes, and increased risk of ovarian hyperstimulation syndrome (OHSS). A potentially effective intervention for women with PCOS-related subfertility involves earlier retrieval of immature oocytes at the germinal-vesicle stage followed by in vitro maturation (IVM). So far, the only data available have derived from observational studies and non-randomised clinical trials.

OBJECTIVES

To assess the effectiveness and safety of IVM followed by IVF or ICSI versus conventional IVF or ICSI among women with PCOS undergoing assisted reproduction.

SEARCH METHODS

This is the second update of this review. We performed the search on 17 April 2018.The search was designed with the help of the Cochrane Gynaecology and Fertility Group Information Specialist, for all published and unpublished randomised controlled trials (RCTs).We searched the the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, CENTRAL via the Cochrane Central Register of Studies Online, MEDLINE, Embase, CINAHL, and the trial registers for ongoing and registered trials and the Open Grey database for grey literature from Europe. We made further searches in the National Institute for Health and Care Excellence (NICE) fertility assessment and treatment guidelines. We handsearched reference lists of relevant systematic reviews and RCTs, together with PubMed and Google for any recent trials that have not yet been indexed in the major databases.

SELECTION CRITERIA

All RCTs on the intention to perform IVM before IVF or ICSI compared with conventional IVF or ICSI for subfertile women with PCOS, irrespective of language and country of origin.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias, extracted data from studies, and attempted to contact the authors of studies for which data were missing. Our primary outcomes were live birth per woman randomised and miscarriage. We performed statistical analysis using Review Manager 5. We assessed evidence quality using GRADE methods.

MAIN RESULTS

We found two RCTs suitable for inclusion in the review and six ongoing trials that have not yet reported results. Both included studies were published as abstracts in international conferences.Both studies were at unclear or high risk of bias for most of the seven domains assessed. Common problems were unclear reporting of study methods and lack of blinding. The main limitations in the overall quality of the evidence were high risk of bias and serious imprecision.There were no data on the primary outcomes of this review, namely live birth per woman randomised and miscarriage.Both studies reported clinical pregnancy rate: there was evidence of an effect between IVM and IVF, favouring the former (odds ratio 3.10, 95% confidence interval 1.06 to 9.00; 71 participants; 2 studies; I² = 0%; very low-quality evidence). The incidence of OHSS was zero in both studies in both groups.There were no data for the other outcomes specified in this review.

AUTHORS' CONCLUSIONS

Though promising data on the in vitro maturation (IVM) technique have been published, unfortunately there is still no evidence from properly conducted randomised controlled trials upon which to base any practice recommendations regarding IVM before in vitro fertilisation (IVF) or intracytoplasmic sperm injection for women with polycystic ovarian syndrome. Regarding our secondary outcomes, very low-quality evidence showed that clinical pregnancy was higher with IVM when compared to IVF, whereas the incidence of ovarian hyperstimulation syndrome was zero in both studies in both groups. We are awaiting the results of six ongoing trials and eagerly anticipate further evidence from good-quality trials in the field.

Observational retrospective study of US national utilisation patterns and live birth rates for various ovarian stimulation protocols for in vitro fertilisation

OBJECTIVE

Alternative ovarian stimulation protocols for in vitro fertilisation (IVF) have grown in popularity. Yet, patient populations best suited for these protocols have not been defined. Our objective was, therefore, to determine national IVF utilisation patterns and live birth rates of various ovarian stimulation protocols.

DESIGN

Retrospective cohort study.

SETTING

Academic-affiliated private fertility centre.

PARTICIPANTS

Aggregate data published by Society for Assisted Reproductive Technology for autologous IVF cycles performed in the USA during 2014 and 2015 were analysed. IVF cycles were stratified based on ovarian stimulation protocol: 205 705 conventional stimulations, 4397 minimal stimulations, 2785 natural cycles and 514 in vitro maturation (IVM) cycles. Repeat cycles could not be determined in this analysis.

OUTCOME MEASURES

Utilisation patterns and age-specific live birth rates for various ovarian stimulation protocols.

RESULTS

With advancing female age, utilisation of conventional stimulation protocols decreased, while minimal stimulation and natural cycle IVF increased. Diminished ovarian reserve diagnoses were in all age groups less prevalent in patients undergoing conventional stimulation than with all other protocols. Live birth rates were highest with conventional stimulation at 42.4%, 33.1%, 22.1%, 11.7% and 3.9% for <35, 35-37, 38-40, 41-42 and >42 female age groups, respectively. The difference in live birth rates between conventional stimulation and other protocols widened with advancing age from 1.6-fold to 3.9-fold among women <35 years of age, reaching 4.4-fold to 6.6-fold among women >42 years of age.

CONCLUSIONS

In comparison to conventional stimulation IVF-minimal stimulation, natural cycle IVF and IVM protocols offer lower but still acceptable live birth rates among young women. These alternative protocols are frequently used in older women and those with diminished ovarian reserve, despite their lower live birth rates. The reasons for this apparent incongruity warrant further careful exploration.

Novel Concepts for Inducing Final Oocyte Maturation in In Vitro Fertilization Treatment

Infertility affects one in six of the population and increasingly couples require treatment with assisted reproductive techniques. In vitro fertilization (IVF) treatment is most commonly conducted using exogenous FSH to induce follicular growth and human chorionic gonadotropin (hCG) to induce final oocyte maturation. However, hCG may cause the potentially life-threatening iatrogenic complication "ovarian hyperstimulation syndrome" (OHSS), which can cause considerable morbidity and, rarely, even mortality in otherwise healthy women. The use of GnRH agonists (GnRHas) has been pioneered during the last two decades to provide a safer option to induce final oocyte maturation. More recently, the neuropeptide kisspeptin, a hypothalamic regulator of GnRH release, has been investigated as a novel inductor of oocyte maturation. The hormonal stimulus used to induce oocyte maturation has a major impact on the success (retrieval of oocytes and chance of implantation) and safety (risk of OHSS) of IVF treatment. This review aims to appraise experimental and clinical data of hormonal approaches used to induce final oocyte maturation by hCG, GnRHa, both GnRHa and hCG administered in combination, recombinant LH, or kisspeptin. We also examine evidence for the timing of administration of the inductor of final oocyte maturation in relationship to parameters of follicular growth and the subsequent interval to oocyte retrieval. In summary, we review data on the efficacy and safety of the major hormonal approaches used to induce final oocyte maturation in clinical practice, as well as some novel approaches that may offer fresh alternatives in future.

In vitro maturation (IVM) of oocytes in patients with resistant ovary syndrome and in patients with repeated deficient oocyte maturation

PURPOSE

To assess the efficiency of IVM in patients with repeated ART failure due to resistant ovary syndrome or due to deficient oocyte maturation.

METHODS

Clinical and laboratory data were obtained retrospectively from 28 patients who underwent 49 cycles of IVM between 2010 and 2017; nine patients had resistant ovary syndrome and 19 patients had repeated deficient oocyte maturation.

RESULTS

Nine patients with resistant ovary syndrome underwent 24 IVM cycles. In those, an average of 11.5 ± 10.4 cumulus-oocyte complexes (COC) was retrieved, and IVM resulted in 3.4 ± 3.1 mature oocytes. After ICSI and transfer of 23 cleavage-stage embryos, eight pregnancies were obtained, resulting in five healthy live births. The live birth rate was 16.7% per started cycle and 33.3% per patient. Nineteen patients with a history of deficient oocyte maturation underwent 25 IVM cycles. An average of 10.6 ± 9.2 COC was retrieved, and after IVM, 1.3 ± 2.1 oocytes were mature. No mature oocytes were obtained in 11 cycles. In ten cycles with mature oocytes, none of them fertilized after ICSI. Out of four cycles with fertilized oocytes, only one good-quality embryo was obtained. No live births were obtained after IVM in patients with a history of deficient oocyte maturation.

CONCLUSIONS

Based on our experience, IVM is a valuable approach in patients with resistant ovary syndrome, but should not be recommended for patients with deficient oocyte maturation.

Oocytes from stem cells

Folliculogenesis describes the process of activating an oocyte-containing primordial follicle from the ovarian reserve and its development to the mature ovulatory stage. This process is highly complex and is controlled by extra- and intra-ovarian signaling events. Oocyte competence and capacity for fertilization to support a viable pregnancy are acquired during folliculogenesis. Cancer and cancer-based therapies can negatively affect this process, compromising fertility. Currently, preservation of fertility in these patients remains limited to surrogacy, oocyte freezing, oocyte donation, or in vitro maturation (IVM). Recent reports of stem cells being used to produce fully competent oocytes and subsequently healthy offspring in mice have opened up a novel avenue for fertility preservation. However, translating these findings into human health first relies on enhancing our understanding of follicle growth and mimicking its intricacies in vitro. Indeed, the future of oocytes from stem cells in humans comes with many possibilities but currently faces several technical and ethical obstacles.

Oocyte in vitro maturation: A sytematic review

In vitro maturation (IVM) is one of the most controversial aspects of assisted reproductive technology. Although it has been studied extensively, it is still not a conventional treatment option and is accepted as an alternative treatment. However, studies have shown that IVM can be used in almost all areas where in vitro fertilization (IVF) is used and it has a strong place in fertility protection and Ovarian Hyperstimulation syndrome management. The aim of this systematic review was to address all aspects of the current knowledge of IVM treatment together with the evolution of IVM and IVF.

Decreased pregnancy and live birth rates after vitrification of in vitro matured oocytes

PURPOSE

To assess effects on fertilization rate, embryo quality, pregnancy, and live birth rates of vitrification and warming of oocytes that matured in vitro (vIVM) compared to fresh in vitro maturation (fIVM) cycles.

METHODS

A retrospective cohort study conducted at a university hospital-affiliated IVF unit. Fifty-six cycles of vIVM cycles and 263 fIVM in women diagnosed with polycystic ovarian syndrome (PCOS) ovaries were included in the analysis. The study group included PCOS patients who failed ovulation induction with intrauterine insemination and were offered IVM cycle followed by oocyte vitrification and warming. The embryological aspects and clinical outcomes were compared to those of controls undergoing fresh IVM cycles during the same period. The main outcome measure was live birth rate.

RESULTS

One thousand seventy oocytes were collected from 56 patients and underwent vitrification and warming. In the control group, 4781 oocytes were collected from 219 patients who had undergone a fresh IVM cycle. Oocyte maturation rates were similar between the groups (mean ± SD: 0.7 ± 0.2 vs. 0.6 ± 0.2, for vIVM and fIVM, respectively). Survival rate after warming was 59.8%. Fertilization and embryo cleavage rates per oocyte were significantly lower in the vIVM group. Clinical pregnancy (10.7 vs. 36.1%) and live birth rates (8.9 vs. 25.9%) per cycle were significantly lower in the vIVM group than those in the fIVM group (P = 0.005 and P < 0.001, respectively). Five healthy babies were born in the vIVM group.

CONCLUSIONS

The reproductive potential of vitrified IVM oocytes is impaired. This injury likely occurs through vitrification and warming.

Current perspectives on in vitro maturation and its effects on oocyte genetic and epigenetic profiles

In vitro maturation (IVM), the maturation in culture of immature oocytes, has been used in clinic for more than 20 years. Although IVM has the specific advantages of low cost and minor side effects over controlled ovarian stimulation, the prevalence of IVM is less than 1% of routine in vitro fertilization and embryo transfer techniques in many reproductive centers. In this review, we searched the MEDLINE database for all full texts and/or abstract articles published in English with content related to oocyte IVM mainly between 2000 and 2016. Many different aspects of the IVM method may influence oocyte potential, including priming, gonadotrophin, growth factors, and culture times. The culture conditions of IVM result in alterations in the oocyte or cumulus cell transcriptome that are not observed under in vivo culture conditions. Additionally, epigenetic modifications, such as DNA methylation or acetylation, are also different between in vitro and in vivo cultured oocytes. In sum, current IVM technique is still not popular and requires more systematic and intensive research to improve its effects and applications. This review will help point our problems, supply evidence or clues for future improving IVM technique, thus assist patients for fertility treatment or preservation as an additional option.

Human oocyte maturation in vitro is improved by co-culture with cumulus cells from mature oocytes

The conventional method of human oocyte maturation in vitro in the presence of gonadotrophins continues to be a relatively low-success procedure in the assisted conception programme owing to suboptimal maturation conditions in the absence of an ovarian 'niche' and poor understanding of this procedure at the molecular level in oocytes. In this study, the gene expression profiles of human oocytes were analysed according to their manner of maturation: in vivo (in the ovaries) or in vitro (matured either by the conventional method or by a new approach - co-cultured with cumulus cells of mature oocytes from the same patient). Our results show that the in-vitro maturation procedure strongly affects the gene expression profile of human oocytes, including several genes involved in transcriptional regulation, embryogenesis, epigenetics, development, and the cell cycle. The in-vitro maturation of oocytes co-cultured with cumulus cells from mature oocytes provides an ovarian 'niche' to some degree, which improves oocyte maturation rates and their gene expression profile to the extent that they are more comparable to oocytes that naturally mature in the ovarian follicle.

Follicle Size on Day of Trigger Most Likely to Yield a Mature Oocyte

OBJECTIVE

To identify follicle sizes on the day of trigger most likely to yield a mature oocyte following hCG, GnRH agonist (GnRHa), or kisspeptin during IVF treatment.

DESIGN

Retrospective analysis to determine the size of follicles on day of trigger contributing most to the number of mature oocytes retrieved using generalized linear regression and random forest models applied to data from IVF cycles (2014-2017) in which either hCG, GnRHa, or kisspeptin trigger was used.

SETTING

HCG and GnRHa data were collected at My Duc Hospital, Ho Chi Minh City, Vietnam, and kisspeptin data were collected at Hammersmith Hospital, London, UK.

PATIENTS

Four hundred and forty nine women aged 18-38 years with antral follicle counts 4-87 were triggered with hCG (n = 161), GnRHa (n = 165), or kisspeptin (n = 173).

MAIN OUTCOME MEASURE

Follicle sizes on the day of trigger most likely to yield a mature oocyte.

RESULTS

Follicles 12-19 mm on the day of trigger contributed the most to the number of oocytes and mature oocytes retrieved. Comparing the tertile of patients with the highest proportion of follicles on the day of trigger 12-19 mm, with the tertile of patients with the lowest proportion within this size range, revealed increases of 4.7 mature oocytes for hCG (P < 0.0001) and 4.9 mature oocytes for GnRHa triggering (P < 0.01). Using simulated follicle size profiles of patients with 20 follicles on the day of trigger, our model predicts that the number of oocytes retrieved would increase from a mean 9.8 (95% prediction limit 9.3-10.3) to 14.8 (95% prediction limit 13.3-16.3) oocytes due to the difference in follicle size profile alone.

CONCLUSION

Follicles 12-19 mm on the morning of trigger administration were most likely to yield a mature oocyte following hCG, GnRHa, or kisspeptin.

The Place of In Vitro Maturation in PCO/PCOS

In vitro maturation (IVM) of human oocytes is an emerging treatment option for women with polycystic ovary/polycystic ovary syndrome (PCO/PCOS) in addition to the standard in vitro fertilization (IVF) treatment. There has been significant improvements in pregnancy rates with IVM over the last two decades. This article reviews the place of IVM for women with PCO/PCOS, placing an emphasis on the predictors of successful pregnancy, optimization of culture media, IVM protocols, pregnancy rates, and neonatal outcomes following IVM treatment.

Development of in vitro maturation techniques for clinical applications

In vitro maturation (IVM) refers to maturation in culture of immature oocytes at different stages that may or may not have been exposed to short courses of gonadotropins. The source of immature oocytes is an important feature for subsequent embryonic development, pregnancy, and healthy live births. IVM is an effective treatment that has already achieved significant outcomes of acceptable pregnancy and implantation rates and has led to the births of several thousand healthy babies. As the development of IVM treatment continues, an attractive possibility for improving the already successful outcome is to combine a natural-cycle in vitro fertilization (IVF) treatment with immature-oocyte retrieval followed by IVM of those immature oocytes. If the treatment processes can be simplified for immature-oocyte retrieval, different types of infertile women may be able to take advantage of these treatments. Mild-stimulation IVF combined with IVM treatment may represent a viable alternative to the standard treatment. Although IVM treatment is still considered to be experimental, it is now time to reconsider the IVM technology and its development. Mild-stimulation IVF combined with IVM may prove to be not just alternatives to standard treatments, but potentially first-line treatment choices.

Predictive factors for live birth after in vitro maturation of oocytes in women with polycystic ovary syndrome

OBJECTIVE

In vitro maturation (IVM) of human oocytes can be an alternative treatment option to conventional in vitro fertilization. Women with polycystic ovary syndrome (PCOS) are considered the classical candidates for IVM because of the associated ovarian morphology and because IVM diminishes the risk of developing ovarian hyperstimulation syndrome. The objective of this study was to identify predictive factors for live birth in a cohort of women with PCOS who underwent IVM.

METHODS

This retrospective study included 159 patients with PCOS who had IVM cycles in which single or double embryo transfer was performed. The IVM protocol included three days of gonadotropin ovarian stimulation and hCG priming when the leading follicle size was 10-12 mm. Collected cumulus-oocyte complexes were cultured for 24 h for maturation. Intracytoplasmic sperm injection (ICSI) was used for fertilization. Embryo transfer was performed two days after fertilization. Demographic and clinical parameters were analyzed with logistic regression to identify predictors for live birth.

RESULTS

The women's mean age was 27.4 years, the mean number of retrieved oocytes was 14, and the live birth rate was 34.6%. The logistic regression revealed the following significant factors for live birth: infertility duration (OR 0.9; 95% CI, 0.82-0.98), number of collected oocytes (OR 1.56; 95% CI, 1.01-3.2), embryo cell number (OR 2.1; 95% CI, 1.4-3.5), and embryo grade (OR 1.84; 95% CI, 1.13-4.2).

CONCLUSION

Infertility duration, oocyte number, embryo cell number, and embryo grade were the most significant predictors for live birth after IVM in PCOS patients. These prognostic factors can be used when planning treatment or counselling patients.

Vitrification of human immature oocytes before and after in vitro maturation: a review

The use of immature oocytes subjected to in vitro maturation (IVM) opens interesting perspectives for fertility preservation where ovarian reserves are damaged by pathologies or therapies, as in PCO/PCOS and cancer patients. Human oocyte cryopreservation may offer some advantages compared to embryo freezing, such as fertility preservation in women at risk of losing fertility due to oncological treatment or chronic disease, egg donation and postponing childbirth. It also eliminates religious and/or other ethical, legal, and moral concerns of embryo freezing. In addition, a successful oocyte cryopreservation program could eliminate the need for donor and recipient menstrual cycle synchronization. Recent advances in vitrification technology have markedly improved the oocyte survival rate after warming, with fertilization and implantation rates comparable with those of fresh oocytes. Healthy live births can be achieved from the combination of IVM and vitrification, even if vitrification of in vivo matured oocytes is still more effective. Recently, attention is given to highlight whether vitrification procedures are more successful when performed before or after IVM, on immature GV-stage oocytes, or on in vitro matured MII-stage oocytes. In this review, we emphasize that, even if there are no differences in survival rates between oocytes vitrified prior to or post-IVM, reduced maturation rates of immature oocytes vitrified prior to IVM can be, at least in part, explained by underlying ultrastructural and biomolecular alterations.

hCG Triggering in ART: An Evolutionary Concept

Human chorionic gonadotropin (hCG) is no longer a single, omnipotent ovulation triggering option. Gonadotropin releasing hormone (GnRH) agonist, initially presented as a substitute for hCG, has led to a new era of administering GnRH agonist followed by hCG triggering. According to this new concept, GnRH agonist enables successful ovum maturation, while hCG supports the luteal phase and pregnancy until placental shift.