Improved implantation and ongoing pregnancy rates after single-embryo transfer with an optimized protocol for in vitro oocyte maturation in women with polycystic ovaries and polycystic ovary syndrome

An update on the current indications for in vitro maturation

PURPOSE OF REVIEW

In vitro maturation has become a significant component of modern assisted reproductive techniques. Published data have been supported for the safety and effectiveness of in vitro maturation treatment. In recent years, potential indications for in vitro maturation (IVM) have been a topic of interest and investigation.

RECENT FINDINGS

Significant improvements in technique enhancement and data publication for evaluating the efficacy of IVM have been achieved. Recent studies have shown that IVM could offer several advantages over in vitro fertilization. Currently, there are growing indications for IVM beyond the commonly mentioned indication of infertile women with polycystic ovary syndrome. Additionally, some potential candidates might have significant advantages for IVM, such as women diagnosed with gonadotropin resistance ovary syndrome or those seeking fertility preservation. With a better understanding of IVM, from basic science to clinical practice, it can be applied safely, effectively, and affordably to a broader range of patients, making it a more accessible and patient-friendly option.

SUMMARY

Despite the possibly acknowledged limitations, the potential of in vitro maturation cannot be denied. As this technique becomes increasingly accessible to patients and more continuous efforts are dedicated to advancing this technique, the impact of in vitro maturation is expected.

Success in Parenthood: The In Vitro Maturation Breakthrough in Infertility

This case report revolves around a 37-year-old woman and her 39-year-old husband, who have been married for seven years and were seeking treatment for infertility. The husband has been diagnosed with asthenozoospermia for the past six years and has been on continued medication, and the woman has been diagnosed with polycystic ovarian syndrome (PCOS). To improve fertility outcomes, this case report enlightens the treatment and medical strategy for people with PCOS. Treatment included low-dose ovarian stimulation for the removal of immature eggs, and then in vitro maturation (IVM) of those oocytes was done. Later, intracytoplasmic sperm injection (ICSI) was performed to form the blast. The formed blasts were later cryopreserved till embryo transfer. This case report highlights the importance of preventing the risk of ovarian hyperstimulation syndrome (OHSS) in patients with PCOS.

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.

The Effect of In Vitro Maturation (IVM) Protocol Changes on Measures of Oocyte/Embryo Competence

Purpose: In vitro maturation (IVM) continues its evolution as new ideas are introduced with the objective of making the IVM procedure easier and more effective. This study combines ideas believed likely to improve the IVM outcome or make the IVM oocyte identification process easier. Methods: A cohort of 45 women underwent an IVM cycle in which letrozole was used with the theoretical objective of improving the competence of small antral follicles, the oocyte aspiration technique was modified to minimize the time between oocyte aspiration and oocyte identification, and blastocysts were transferred during a subsequent cycle with controlled endometrial development. Results: Measures of oocyte competence used for these prospectively followed cycles were as follows: the maturation rate was 90.5%, the fertilization rate was 92.4%, the cleavage rate was 94.6%, the usable blastulation rate per zygote was 50.2%, and the implantation rate was 34.2%. Per transfer, the biochemical pregnancy rate was 63.2%, the clinical pregnancy rate was 55.3% and the ongoing/delivered pregnancy rate at the end of the first trimester was 47.4%. The miscarriage rate for clinical pregnancies in the first trimester was 14.3% and the ongoing twinning rate was 11.1%.

In vitro maturation without gonadotropins versus in vitro fertilization with hyperstimulation in women with polycystic ovary syndrome: a non-inferiority randomized controlled trial

STUDY QUESTION

Does in vitro maturation (IVM) result in non-inferior cumulative live birth rates compared to those after standard in vitro fertilization (IVF) in infertile women with polycystic ovary syndrome (PCOS)?

SUMMARY ANSWER

One cycle of IVM, without any stimulation, was inferior to one cycle of standard IVF in women with PCOS in terms of 6-month cumulative live birth rates, when choosing single vitrified-warmed blastocyst transfer.

WHAT IS KNOWN ALREADY

IVM is an emerging alternative treatment for women with PCOS who need assisted reproductive technology. Since a minimal or even zero dose of gonadotropins are required in the IVM procedure, the occurrence of ovarian hyperstimulation syndrome (OHSS) is eliminated. Only one clinical trial comparing the pregnancy outcome between IVM with FSH priming and IVF has been reported. However, it is still unknown whether IVM treatment without any stimulation can offer a similar live birth outcome in women with PCOS as compared to that in women receiving the standard IVF procedure with ovarian stimulation.

STUDY DESIGN, SIZE, DURATION

This single-centre, open-label randomized controlled non-inferiority trial in an academic infertility centre in China was performed between March 2018 and July 2019.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women aged 20-38 years with PCOS and infertility scheduled for their first IVF attempt were eligible. In total, 351 women were randomly allocated to receive one cycle of unstimulated IVM (n = 175) or one cycle of standard IVF with a flexible GnRH antagonist protocol and hCG as ovulatory trigger (n = 176). A freeze-all and single blastocyst transfer strategy was used in both groups. The primary outcome was ongoing pregnancy (leading to live birth) within 6 months after randomization. A non-inferiority margin of 15% was considered.

MAIN RESULTS AND THE ROLE OF CHANCE

The IVM procedure without additional gonadotropin resulted in a lower ongoing pregnancy (leading to live birth) within 6 months after randomization compared to standard IVF treatment (22.3% vs. 50.6%; rate difference -28.3%; 95% confidence interval [CI]: -37.9% to -18.7%). Moderate-severe OHSS did not occur in the IVM group, while in the IVF group, ten women (5.7%) had moderate OHSS and one woman (0.6%) had severe OHSS. There was no statistically significant difference in the occurrence of obstetric and perinatal complications.

LIMITATIONS, REASONS FOR CAUTION

The trial was conducted using an IVM protocol without additional stimulation in a single centre, which may limit its generalizability. In addition, a GnRH agonist trigger rather than hCG for IVF stimulation in women with PCOS would be more consistent with current clinical practice.

WIDER IMPLICATIONS OF THE FINDINGS

Although IVM is considered to be a convenient, inexpensive and safe alternative to IVF for women with PCOS, our results indicated that one cycle of IVM without any stimulation was inferior to one cycle of standard IVF in terms of the cumulative live birth rate. The inferiority of IVM without ovarian stimulation could be mainly due to the limitations in the developmental potential of embryos. Further IVM development should be tested and validated in a freeze-only and blastocyst transfer setting. Further RCTs are needed to evaluate the effectiveness and safety of other IVM protocols or multiple cycles of IVM compared to IVF.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the National Key Research and Development Program of China (2016YFC1000201 and 2018YFC1002104) and the National Science Foundation of China (81730038). B.W.M. is supported by a NHMRC Investigator grant (GNT1176437). All other authors declare no competing interests.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov NCT03463772.

TRIAL REGISTRATION DATE

29 January 2018.

DATE OF FIRST PATIENT’S ENROLMENT

16 March 2018.

Twenty-first century oocyte cryopreservation—in vitro maturation of immature oocytes from ovarian tissue cryopreservation in cancer patients: A systematic review

Objectives:

Our review aimed to consolidate the latest update on the application of in vitro maturation among immature oocyte harvest in combination with ovarian tissue cryopreservation known as ovarian tissue oocyte–in vitro maturation.

Methods:

A thorough search for relevant studies was conducted via PubMed, Google Scholar, EMBASE, and clinical.gov databases up to December 2020. The primary outcome was the oocyte maturation rate, which measured the number of immature oocytes (geminal vesicle stage) that progressed to mature oocytes (meiosis II stage) following in vitro maturation. The secondary outcomes were the fertilization rate following intracytoplasmic sperm injection/in vitro fertilization of these oocytes for the embryo cryopreservation cohort. Our review included pre-pubertal girls and women with cancer who underwent ovarian tissue oocyte–in vitro maturation as fertility preservation.

Results:

The primary search identified 207 studies. Twelve manuscripts were selected for inclusion in our review following duplication assessment, title and abstract screening, and full-text evaluation tailored to our inclusion criteria. All the population belonged to a cancer group and underwent concurrent ovarian tissue oocyte–in vitro maturation. A total of 5724 immature oocytes were obtained following ovarian tissue cryopreservation. Approximately 33.84% of the immature oocytes successfully matured via in vitro maturation, which were cryopreserved as oocytes or fertilized as embryos and subsequently stored for future use.

Conclusion:

Our review proposed the potential application of ovarian tissue oocyte–in vitro maturation in increasing the number of mature oocytes. The acceptable improvement in oocyte maturation rate following in vitro maturation indicates that improving oocyte outcomes is an excellent cost-effective strategy for fertility preservation among women with cancer.

In vitro maturation of immature oocytes for fertility preservation in cancer patients compared to control patients with fertility problems in an in vitro fertilization program

Background

The aim of this study was to determine whether in vitro maturation (IVM) of immature oocytes after controlled hormonal stimulation of the ovaries could be important in cancer patients to improve their chances of conception in the future.

Patients and methods

After ovarian stimulation in cancer patients, the number of oocytes and their quality and maturity were compared to control patients with fertility problems in the in vitro fertilization (IVF) program. In both groups of patients, immature oocytes at the developmental stage of germinal vesicle were matured in vitro and the proportion of oocytes that matured in vitro was compared between groups. In a subset of women with fertility problems, intracytoplasmic sperm injection (ICSI) was performed on IVM oocytes to assess their ability to be fertilized and develop into an embryo compared to vivo matured oocytes in the same cycles and consider the procedure in cancer patients.

Results

In patients with different cancers, the disease did not affect the number and quality of retrieved oocytes. In cancer patients, there was even a significantly lower proportion of immature oocytes than in patients with fertility problems (30.0% vs. 43.6%; P < 0.05). However, in patients with cancer, fewer oocytes per patient matured in vitro than in patients with fertility problems (1.39 ± 1.04 vs. 2.48 ± 1.83; P < 0.05). After ICSI, the proportions of fertilized oocytes and fertilized oocytes developing into an embryo did not differ between oocytes matured in vitro and in vivo in the same cycles.

Conclusions

Oocyte IVM is proving to be a reliable procedure for resolving immature oocytes after controlled ovarian stimulation in cancer patients.

Factors Influencing the In Vitro Maturation (IVM) of Human Oocyte

In vitro maturation (IVM) of oocytes is a promising assisted reproductive technology (ART) deemed as a simple and safe procedure. It is mainly used in patients with impaired oocyte maturation and in fertility preservation for women facing the risk of losing fertility. However, to date, it is still not widely used in clinical practice because of its underperformance. The influencing factors, such as biphasic IVM system, culture medium, and the supplementation, have a marked effect on the outcomes of oocyte IVM. However, the role of different culture media, supplements, and follicular priming regimens in oocyte IVM have yet to be fully clarified and deserve further investigation.

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.

A threshold concentration of FSH is needed during IVM of ex vivo collected human oocytes

PURPOSE

To investigate the effect of different FSH concentrations on human oocyte maturation in vitro and its impact on gene expression of key factors in the surrounding cumulus cells.

METHODS

The study included 32 patients who underwent unilateral oophorectomy for ovarian tissue cryopreservation (OTC) (aged 28 years on average). Immature oocytes were collected from surplus medulla tissue. A total of 587 immature oocytes were divided into three categories according to the size of the cumulus mass: large (L-COCs), small (S-COCs), and naked oocytes (NOs), and submitted to 44-h IVM with one of the following concentrations of recombinant FSH: 0 IU/L, 20 IU/L, 40 IU/L, 70 IU/L, or 250 IU/L. After IVM, oocyte nuclear maturation stage and diameter were recorded. The relative gene expression of FSHR, LHCGR, and CYP19A1 in cumulus cells before (day 0; D0) and after IVM were evaluated.

RESULTS

Addition of 70 or 250 IU/L FSH to the IVM medium improved oocyte nuclear maturation compared to 0, 20, and 40 IU/L FSH by upregulating LHCGR and downregulating FSHR in the cumulus cells.

CONCLUSION

FSH improved oocyte nuclear maturation at concentrations above 70 IU/L suggesting a threshold for FSH during IVM of ex vivo collected human oocytes from small antral follicles. Moreover, current results for the first time highlight that FSH function in vitro is mediated via cumulus cells by downregulating FSHR and upregulating LHCGR, which was also observed when the immature oocytes progressed in meiosis from the GV to the MII stage.

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.

Double HCG trigger improves recovery of oocytes in women with a paucifollicular response to ovarian stimulation: A pilot study

OBJECTIVE

To examine whether adding a second HCG trigger, 12.5 h after the first (36.5 h before ovarian puncture), can facilitate recovery of oocytes in women with a paucifollicular response to ovarian stimulation.

METHODS

A total of 85 women aged 35-42 years, with a paucifollicular response to ovarian stimulation and who had experienced a total failure of oocyte recovery after the standard HCG ovulation trigger 36.5 h before ovarian puncture, were subsequently treated by the same protocol but with the addition of a second HCG trigger 12.5 h later. The recovered oocytes were inseminated by intracytoplasmic sperm injection (ICSI) and all available embryos were transferred 3 days later.

RESULTS

The double trigger enabled recovery of cumulus oophorus cells from most of the follicles in the women who experienced failure of total recovery of oocytes after a single trigger. Fifteen patients became pregnant, and no signs of ovarian hyperstimulation syndrome were observed. Nine women delivered a healthy child.

CONCLUSION

In women aged 35-42 years with a paucifollicular response to ovarian stimulation, a double HCG trigger appears to improve the rate of oocyte recovery. The conclusion of this pilot study needs to be confirmed by larger prospective trials.

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.

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.

Selection of competent oocytes by morphological criteria for assisted reproductive technologies

Invasive and noninvasive methods are commonly used to select developmentally competent oocytes that can improve the take-home baby rates in assisted reproductive technology (ART) centers. One of the noninvasive methods conventionally utilized to determine competent oocytes is the morphological analysis of cumulus complex, first polar body, zona pellucida, perivitelline space, meiotic spindle, and ooplasm. Successful fertilization, early embryo development, uterine implantation, and healthy pregnancy depend on the quality of oocytes, and morphological evaluation is one of the options used to predict quality levels. In this review, the morphological criteria being utilized in certain ART centers are comprehensively evaluated with special references to their predictive values and potential contributions to selecting high-quality oocytes.

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.

The effect of insemination methods on in vitro maturation outcomes

Objective

The aim of this study was to compare the effects of conventional insemination (in vitro fertilization [IVF]) and intracytoplasmic sperm injection (ICSI) on the fertilization, developmental competence, implantation potential, and clinical pregnancy rate of embryos derived from in vitro matured oocytes of patients with polycystic ovary syndrome (PCOS).

Methods

A prospective study was carried out among 38 PCOS patients who had undergone in vitro maturation (IVM) treatment. In total, 828 immature oocytes were collected from 42 cycles and randomly assigned for insemination by IVF (416 oocytes) or ICSI (412 oocytes). After fertilization, the embryos were cultured until the blastocyst stage and single embryos were transferred after endometrial preparation and under ultrasound guidance.

Results

No significant differences were found in the maturation rate (78.1% vs. 72.6% for IVF and ICSI insemination, respectively; p= 0.076), fertilization rate (59.4% vs. 66.9% for IVF and ICSI insemination, respectively; p= 0.063), or the formation of good-quality blastocysts (40.9% vs. 46.5% for IVF and ICSI insemination, respectively; p= 0.314). Implantation and clinical pregnancy also did not show significant differences.

Conclusion

There was a comparable yield of in vitro matured oocytes derived from PCOS patients in terms of fertilization, blastocyst formation, implantation rate, and clinical pregnancy between IVF and ICSI insemination. These findings provide valuable insights for choosing assisted reproductive treatment in women with PCOS, as IVM offers promising outcomes and is less invasive and less costly.

The perspective of women with an increased risk of OHSS regarding the safety and burden of IVF: a discrete choice experiment

STUDY QUESTION

What are the preferences of women with an increased risk of ovarian hyperstimulation syndrome (OHSS) for characteristics of IVF treatments?

SUMMARY ANSWER

In women with increased risk of OHSS, the chance of OHSS is a strong attribute in determining women's preference for IVF treatment and women are willing to trade off burden (side effects), costs and chance of pregnancy for lower risks of OHSS.

WHAT IS KNOWN ALREADY

OHSS is the most serious iatrogenic complication of ovarian stimulation. Polycystic ovaries, high antral follicle count (AFC) and previous OHSS increase the risk of developing OHSS. IVM of oocytes offers great potential for patients with high AFC, since there is no risk of OHSS. With regard to patients' perspectives on fertility treatments, it has been shown that women undergoing IVF place different values on treatment characteristics, such as effectiveness (pregnancy rate), cancellation risk, safety (OHSS risk) and burden (side effects). To our knowledge, the preferences for different IVF treatments in women with increased risk of OHSS have not been studied yet.

STUDY DESIGN SIZE DURATION

A multicentre discrete choice experiment (DCE) was performed between 2012 and 2016. The selected attributes offered were chance of OHSS, which represents safety; number of injections; chance of cycle cancellation (the latter two represent burden); chance of pregnancy; and out-of-pocket costs/willingness to pay. A target sample size was calculated by including 20 patients for five attributes resulting in the aim to include 100 women.

PARTICIPANTS/MATERIALS SETTING METHODS

We invited subfertile women who were diagnosed with normogonadotrophic ovulation disorder and were undergoing treatment with gonadotrophins and/or had experienced (imminent) OHSS in a previous IVF treatment in the fertility clinic of four hospitals (three teaching and one academic). Women received a printed questionnaire with fictional scenarios and were asked, for each scenario, to choose their preferred treatment. We used a multinominal logit model to determine the preferences of women and investigated heterogeneity in preferences through latent class analysis. The decrease in OHSS risk required for women to accept an increased level of an undesirable attribute, i.e. their willingness to trade off, was calculated.

MAIN RESULTS AND THE ROLE OF CHANCE

We distributed 120 questionnaires with a response rate of 79% (95/120). There were 91 questionnaires included in the analysis. All five attributes influenced women's treatment preference. About half of the women considered chance of pregnancy to be more important, while the other half considered prevention of OHSS and lower costs to be more important. Women were willing to trade off cancellation rate, number of injections, chance of pregnancy and costs for lower OHSS chances. We found that women were willing to accept 5% more chance on cycle cancellation if the OHSS rate dropped with 2%. Women were willing to accept one extra treatment for a reduction of 3.9% in OHSS risk. With respect to costs, women were willing to pay €1000 instead of no costs for a decrease in OHSS rate of 5.4%.

LIMITATIONS REASONS FOR CAUTION

The sample size of our study is relatively small which may limit the generalizability and sensitivity of the study.

WIDER IMPLICATIONS OF THE FINDINGS

The results of this DCE help us to understand the trade-off that women at risk of OHSS make in their preference for characteristics on IVF treatments. This knowledge may be used during the counselling of couples about their treatment options.

STUDY FUNDING/COMPETING INTERESTS

B.W.M. is supported by a NHMRC Practitioner Fellowship (GNT1082548). B.W.M. reports consultancy for Merck, ObsEva and Guerbet. J.P.d.B. reports personal fees from the Ferring Medical Advisory Board and grants from Ferring B. V and Merck Serono B. V outside the submitted work. There are no other conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

None.

Luteinizing Hormone Action in Human Oocyte Maturation and Quality: Signaling Pathways, Regulation, and Clinical Impact

The ovarian follicle luteinizing hormone (LH) signaling molecules that regulate oocyte meiotic maturation have recently been identified. The LH signal reduces preovulatory follicle cyclic nucleotide levels which releases oocytes from the first meiotic arrest. In the ovarian follicle, the LH signal reduces cyclic nucleotide levels via the CNP/NPR2 system, the EGF/EGF receptor network, and follicle/oocyte gap junctions. In the oocyte, reduced cyclic nucleotide levels activate the maturation promoting factor (MPF). The activated MPF induces chromosome segregation and completion of the first and second meiotic divisions. The purpose of this paper is to present an overview of the current understanding of human LH signaling regulation of oocyte meiotic maturation by identifying and integrating the human studies on this topic. We found 89 human studies in the literature that identified 24 LH follicle/oocyte signaling proteins. These studies show that human oocyte meiotic maturation is regulated by the same proteins that regulate animal oocyte meiotic maturation. We also found that these LH signaling pathway molecules regulate human oocyte quality and subsequent embryo quality. Remarkably, in vitro maturation (IVM) prematuration culture (PMC) protocols that manipulate the LH signaling pathway improve human oocyte quality of cultured human oocytes. This knowledge has improved clinical human IVM efficiency which may become a routine alternative ART for some infertile patients.

Biphasic in vitro maturation (CAPA-IVM) specifically improves the developmental capacity of oocytes from small antral follicles

PURPOSE

To investigate the effectiveness of a biphasic IVM culture strategy at improving IVM outcomes in oocytes from small follicles (< 6 mm) compared with routine Standard IVM in patients with polycystic ovaries.

METHODS

This prospective pilot study was performed in 40 women with polycystic ovaries whose oocytes were randomized to two IVM culture methods. Patients received a total stimulation dose of 450 IU rFSH. Cumulus-oocyte complexes (COCs) from follicles < 6 mm and ≥ 6 mm were retrieved and cultured separately in either a prematuration medium with c-type natriuretic peptide followed by IVM (CAPA-IVM), or STD-IVM. Primary outcomes were maturation rate, embryo quality, and the number of vitrified day 3 embryos per patient.

RESULTS

Use of the CAPA-IVM system led to a significant improvement in oocyte maturation (p < 0.05), to a doubling in percentage of good and top-quality day 3 embryos per COC, and to an increased number of vitrified day 3 embryos (p < 0.001), compared to STD IVM. Oocytes from follicles < 6 mm benefited most from CAPA-IVM, showing a significant increase in the amount of good and top-quality embryos compared to STD IVM. CAPA-IVM yielded significantly (p < 0.0001) less GV-arrested oocytes and larger oocyte diameters (p < 0.05) than STD IVM.

CONCLUSIONS

CAPA-IVM brings significant improvements in maturation and embryological outcomes, most notably to oocytes from small antral follicles (< 6 mm), which can be easily retrieved from patients with a minimal ovarian stimulation. The study demonstrates the robustness and transferability of the CAPA-IVM method across laboratories and populations.

The Place of In Vitro Maturation in Assisted Reproductive Technology

In vitro maturation (IVM) is an assisted reproductive technology (ART) whereby immature cumulus-oocyte complexes are collected and matured in vitro, without need for controlled ovarian stimulation and ovulation triggering. Advantages of IVM over in vitro fertilization (IVF) include mild or no stimulation, lower medication costs and less patient burden. However, early clinical outcomes with IVM were suboptimal. More recently, clinical studies reported live birth rates after IVM of about 40%. New IVM culture systems are being used to improve the efficacy of IVM. These have been in widespread use for animals for many years and are now showing promise in the clinical setting. Patients more likely to benefit from IVM over IVF include those at risk of OHSS (e.g. women with polycystic ovary syndrome), when the time for ovarian stimulation is limited, or where sustained elevations of estradiol are contraindicated (e.g. oncofertility indications). The main barrier to use of IVM to date was its relative efficacy compared with IVF, and there have also been concerns over the health of infants born following IVM. However, no differences in congenital abnormalities between IVM and other ARTs have been identified. In addition, there is a lack of both experience and standardized protocols. Strategies to overcome barriers to the use of IVM include better training for clinicians, more and better funded research in the field, and improved recognition of IVM by fertility specialists. Overall, IVM offers a valuable alternative for ART in select patient populations. New approaches to IVM appear to have the potential to achieve pregnancy outcomes equivalent to those after IVF. Increasing the use of IVM in the future can be achieved with improved training and education for fertility specialists, and increased funding for IVM research, with the ultimate goal of improving fertility outcomes.

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.

Comparison of GnRH agonist and hCG for priming in vitro maturation cycles in cancer patients undergoing urgent fertility preservation

In vitro maturation (IVM) of oocytes retrieved at germinal vesicle or Metaphase I stage, followed by vitrification of Metaphase II (MII) oocytes, has recently emerged as an option for urgent fertility preservation (FP). Priming is usually achieved with an injection of hCG, 10,000 IU, 36 hours before retrieval. This study aimed to assess a new method of priming, using GnRH agonists, and compare it to hCG, in cancer patients undergoing urgent FP. From 2009 to 2015, 373 cancer patients underwent MII oocyte cryopreservation after IVM cycles primed either with GnRHa (triptorelin 0.2 mg) (n = 138) or hCG (10,000 IU) (n = 235). Patients’ characteristics were comparable between the two groups. The number of COC retrieved was significantly higher in the GnRHa group (9.1 ± 6.8 versus 7.7 ± 5.5 oocytes, p = 0.04). However, the maturation rates (59 ±25% versus 64 ±26%, p = 0.07, respectively), and the total number of MII oocytes frozen (5.2 ±4.2 versus 4.9 ±4.0, p = 0.6, respectively) were similar between the GnRha and hCG groups. We did not find any difference between GnRHa and hCG priming for IVM. GnRHa priming is more physiological since it stimulates endogenous FSH and LH activity, and is well suited for FP in hormone-sensitive cancers and urgent cases.

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.

Live birth rate after human chorionic gonadotropin priming in vitro maturation in women with polycystic ovary syndrome

BACKGROUND

In vitro maturation (IVM) has some advantages over conventional in vitro fertilization (IVF), particularly in polycystic ovary syndrome (PCOS) where the risk of ovarian hyperstimulation is high. We studied the live birth rate in a large series of PCOS women undergoing human chorionic gonadotropin (hCG)-priming IVM.

METHODS

This retrospective study included women with PCOS aged 18-42 years undergoing IVM with hCG priming. We reported live birth rate after the first embryo transfer and cumulative live birth rate from embryos obtained in the IVM cycle. We also performed logistic regression to assess which factors predicted number of oocytes and live birth.

RESULTS

We included 921 women (age 28.9±3.5 years, body mass index 21.8±3.1 kg/m2, infertility duration 3.7±2.6 years, 81% primary infertility, 88% first IVF attempt, 94% ovulation induction failure). Live birth rate after the first embryo transfer was 31.7%, with a cumulative live birth rate from the cycle of 33.7%. High anti-Müllerian hormone levels predicted a high number of oocytes and a high oocyte maturation rate while the opposite was the case when luteinizing hormone levels were high.

CONCLUSIONS

In women with PCOS, hCG priming IVM was feasible and resulted in acceptable live birth rates.

In vitro maturation

In vitro maturation (IVM) is an in vitro fertilisation (IVF) technique modified to collect immature oocytes from antral follicles, with the final stages of meiosis completed during in vitro culture. The primary benefit of IVM is that it reduces gonadotrophin stimulation in the patient, thereby eliminating the risk of ovarian hyperstimulation syndrome (OHSS) in high-risk patients such as those with polycystic ovaries (PCO) and polycystic ovary syndrome (PCOS). IVM has additional benefits for fertility preservation, particularly in oncofertility patients. IVM research has progressed in recent years to significantly improve success rates and to provide evidence of safety in terms of neonatal and childhood outcomes. More recently, pre-maturation protocols and the discovery of new culture media additives have demonstrated potential to maximise maturation and oocyte developmental competence. In this chapter, we discuss current methodologies used in clinics routinely performing IVM, target patient populations and areas of future research that may improve IVM success.

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.

Occurrence of ovarian follicular dominance during stimulation for IVM impacts usable blastocyst yield

OBJECTIVE

To evaluate the influence of ovarian follicular dominance on the outcome of oocyte in-vitro maturation.

METHODS

This retrospective cohort study included 21 patients with polycystic ovaries or polycystic ovary syndrome (Rotterdam criteria, 2004) subjected to 24 invitro maturation (IVM) cycles between October 2015 and January 2017. Patients undergoing IVM received minimal gonadotropin stimulation starting on day 2 or 3 of the cycle; ovum pick-up typically occurred on days 6 to 8. No hCG-trigger shot was given. Following 30h of IVM, mature oocytes were inseminated by ICSI and the resulting embryos cultured up to the blastocyst stage.

RESULTS

Ovarian follicular dominance was observed in nine of the 24 IVM cycles. Oocyte IVM yielded an overall maturation rate of 69.3±23.8%, and no difference was observed when the groups with or without a dominant follicle were assessed independently. The rates of fertilization and usable blastocysts per fertilized oocyte, mature oocyte (Metaphase II) or cumulus-oocyte-complex were nearly three times higher (28.7±22.5%) in the group without ovarian follicular dominance. No differences were found in the clinical pregnancy rates attained by the individuals with or without a dominant follicle after 21 vitrified-warmed blastocyst transfer cycles.

CONCLUSION

Occurrence of ovarian follicular dominance during hormonal stimulation for in-vitro maturation negatively impacted embryological outcomes. Strategies devised to limit the appearance of ovarian follicular dominance must be further explored.

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.

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.

Mosaic embryo transfer after oocyte in vitro maturation in combination with non-invasive prenatal testing (NIPT)-first report of a euploid live birth

PURPOSES

The purpose of this study is to describe a healthy life birth after a mosaic embryo transfer in oocyte in vitro maturation (IVM).

METHODS

Patient received minimal stimulation, starting on day 3 after menstrual period. No hCG trigger was administered. Oocyte retrieval was performed and oocytes were matured for 30 h. After denuding, mature oocytes were inseminated by ICSI. Embryos were cultured until blastocyst stage and biopsied.

RESULTS

One euploid embryo after array comprehensive genome hybridization (aCGH) was diagnostic. However, the next-generation sequencing (NGS) re-analysis showed that embryo was a mosaic for chromosome 13 and 21. Nevertheless, pregnancy ultrasound scans and non-invasive prenatal test (NIPT-Verifi-Illumina) indicated a normal fetus development. Finally, a healthy baby was born after 38 weeks. Its weight was 4480 g, head circumference 36 cm, and total length of 51 cm. To confirm that the baby was chromosomically normal, an NGS test was performed in buccal cells, a normal profile was obtained.

CONCLUSIONS

Our finding confirmed that mosaic embryo transfer would bring a healthy offspring.

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

Aim

In 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.

Methods

Based 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.

Results

Although 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.

Conclusion

Regarding 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.

Outcomes of immature oocytes collected from ovarian tissue for cryopreservation in adult and prepubertal patients

The efficiency of oocyte in-vitro maturation (IVM) and vitrification procedures after ex-vivo collection from ovarian tissue were assessed according to patient age, number of retrieved oocytes and tissue transport conditions. The combined procedure was performed in 136 patients: 130 adults (mean 27.6 ± 5.6 years) and six prepubertal girls (mean 8.7 ± 2.3 years). A higher mean number of oocytes were collected in girls compared with adults (11.5 ± 8.0 versus 3.8 ± 4.2, respectively, P < 0.001) but the percentage of degenerated oocytes was significantly higher in girls (35.5% versus 17.1%, respectively, P < 0.001). IVM rates were significantly lower in prepubertal than postpubertal population (10.3% versus 28.1%, P = 0.002). In adults, a negative correlation was observed between number of retrieved oocytes and age (P = 0.002; r = -0.271); the correlation was positive between anti-Müllerian hormone (AMH) and number of collected oocytes (P = 0.002; r = 0.264). IVM rates were not correlated with AMH levels (r = 0.06) or age (r = -0.033). At present, nine oocytes and one embryo have been warmed in four patients and one biochemical pregnancy obtained. This suggests the combined procedure could be an additional option for fertility preservation.

Single-cell analysis of differences in transcriptomic profiles of oocytes and cumulus cells at GV, MI, MII stages from PCOS patients

Polycystic ovary syndrome (PCOS) is a common frequent endocrine disorder among women of reproductive age. Although assisted reproductive techniques (ARTs) are used to address subfertility in PCOS women, their effectiveness is not clear. Our aim was to compare transcriptomic profiles of oocytes and cumulus cells (CCs) between women with and without PCOS, and assess the effectiveness of ARTs in treating PCOS patients. We collected oocytes and CCs from 16 patients with and without PCOS patients to categorize them into 6 groups according to oocyte nuclear maturation. Transcriptional gene expression of oocyte and CCs was determined via single-cell RNA sequencing. The ratio of fertilization and cleavage was higher in PCOS patients than in non-PCOS patients undergoing ARTs, and there was no difference in the number of high-quality embryos between the groups. Differentially expressed genes including PPP2R1A, PDGFRA, EGFR, GJA1, PTGS2, TNFAIP6, TGF-β1, CAV1, INHBB et al. were investigated as potential causes of PCOS oocytes and CCs disorder at early stages, but their expression returned to the normal level at the metaphase II (MII) stage via ARTs. In conclusion, ARTs can improve the quality of cumulus-oocyte complex (COC) and increase the ratio of fertilization and cleavage in PCOS women.

Oocyte maturation and quality: role of cyclic nucleotides

The cyclic nucleotides, cAMP and cGMP, are the key molecules controlling mammalian oocyte meiosis. Their roles in oocyte biology have been at the forefront of oocyte research for decades, and many of the long-standing controversies in relation to the regulation of oocyte meiotic maturation are now resolved. It is now clear that the follicle prevents meiotic resumption through the actions of natriuretic peptides and cGMP - inhibiting the hydrolysis of intra-oocyte cAMP - and that the pre-ovulatory gonadotrophin surge reverses these processes. The gonadotrophin surge also leads to a transient spike in cAMP in the somatic compartment of the follicle. Research over the past two decades has conclusively demonstrated that this surge in cAMP is important for the subsequent developmental capacity of the oocyte. This is important, as oocyte in vitro maturation (IVM) systems practised clinically do not recapitulate this cAMP surge in vitro, possibly accounting for the lower efficiency of IVM compared with clinical IVF. This review particularly focuses on this latter aspect - the role of cAMP/cGMP in the regulation of oocyte quality. We conclude that clinical practice of IVM should reflect this new understanding of the role of cyclic nucleotides, thereby creating a new generation of ART and fertility treatment options.

What threshold values of antral follicle count and serum AMH levels should be considered for oocyte cryopreservation after in vitro maturation?

STUDY QUESTION

What threshold values of ultrasonographic antral follicle count (AFC) and serum anti-Müllerian hormone (AMH) levels should be considered for ensuring the cryopreservation of sufficient number of in vitro matured (IVM) oocytes, in cancer patients seeking fertility preservation (FP)?

SUMMARY ANSWER

AFC and serum AMH values >20 follicles and 3.7 ng/ml, respectively, are required for obtaining at least 10 IVM oocytes for cryopreservation.

WHAT IS KNOWN ALREADY

IVM of cumulus oocyte complexes (COCs) followed by oocyte cryopreservation has emerged recently as an option for urgent FP. Recent data have reported that, in healthy patients, 8-20 cryopreserved oocytes after ovarian stimulation would maximize the chance of obtaining a live birth. Although both AFC and AMH have been reported as predictive factors of IVM success in infertile patients with polycystic ovary syndrome (PCOS), there is a dramatic lack of data regarding the values of these parameters in oncological patients as candidates for FP.

STUDY DESIGN, SIZE, DURATION

From January 2009 to April 2015, we prospectively studied 340 cancer patients, aged 18-41 years, as candidates for oocyte cryopreservation following IVM.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All patients had AFC and AMH measurements, 48-72 h before oocyte retrieval, regardless of the phase of the cycle. COCs were recovered under ultrasound guidance 36 h after hCG priming. Logistic regression allowed the determination of threshold values of AFC and AMH, for obtaining at least 8, 10 or 15 matures oocytes frozen after the IVM procedure. Similar analyses were performed for a final number of mature oocytes ≤2.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 340 cancer patients included, 300 were diagnosed with breast cancers, 14 had hematological malignancies and 26 underwent the procedure for others indications. Overall, the mean age of the population was 31.8 ± 4.5 years. Mean AFC and serum AMH levels were 21.7 ± 13.3 follicles and 4.4 ± 3.8 ng/ml, respectively. IVM was performed in equal proportions during the follicular or luteal phase of the cycle (49 and 51%, respectively). Statistical analysis showed that AFC and AMH values above 28 follicles and 3.9 ng/ml, 20 follicles and 3.7 ng/ml and 19 follicles and 3.5 ng/ml are required, respectively, for obtaining at least 15, 10 or 8 frozen IVM oocytes with a sensitivity ranging from 0.82 to 0.90. On the contrary, ≤2 IVM oocytes were cryopreserved when AFC and AMH were <19 follicles and 3.0 ng/ml, respectively.

LIMITATIONS, REASONS FOR CAUTION

Although the potential of cryopreserved IVM oocytes from cancer patients remains unknown, data obtained from infertile PCOS women have shown a dramatically reduced competence of these oocytes when compared with that of oocytes recovered after ovarian stimulation. As a consequence, the optimal number of IVM oocytes frozen in candidates for FP is currently unpredictable.

WIDER IMPLICATIONS OF THE FINDINGS

Cryopreservation of oocytes after IVM should be considered in the FP strategy when ovarian stimulation is unfeasible, in particular when markers of the follicular ovarian status are at a relatively high range. Further investigation is needed to objectively assess the real potential of these IVM oocytes after cryopreservation. Therefore, even when a good COCs yield is expected, we should systematically encourage IVM in combination with ovarian tissue cryopreservation.

STUDY FUNDING/COMPETING INTERESTS

No external funding was obtained for the present study. The authors have no conflict of interest to declare.

TRIAL REGISTRATION NUMBER

Not applicable.

Prediction of Ovarian Hyperstimulation Syndrome in Patients Treated with Corifollitropin alfa or rFSH in a GnRH Antagonist Protocol

Study Question

What is the threshold for the prediction of moderate to severe or severe ovarian hyperstimulation syndrome (OHSS) based on the number of growing follicles ≥ 11 mm and/or estradiol (E₂) levels?

Summary Answer

The optimal threshold of follicles ≥11 mm on the day of hCG to identify those at risk was 19 for both moderate to severe OHSS and for severe OHSS. Estradiol (E₂) levels were less prognostic of OHSS than the number of follicles ≥ 11 mm.

What Is Known Already

In comparison to long gonadotropin-releasing hormone (GnRH) agonist protocols, the risk of severe OHSS is reduced by approximately 50% in a GnRH antagonist protocol for ovarian stimulation prior to in vitro fertilisation (IVF), while the two protocols provide equal chances of pregnancy per initiated cycle. Nevertheless, moderate to severe OHSS may still occur in GnRH antagonist protocols if human chorionic gonadotropin (hCG) is administered to trigger final oocyte maturation, especially in high responder patients. Severe OHSS following hCG trigger may occur with an incidence of 1–2% in a relatively young (aged 18 to 36 years) IVF population treated in a GnRH-antagonist protocol.

Study Design, Size, Duration

From the Engage, Ensure and Trust trials, in total, 2,433 women who received hCG for oocyte maturation and for whom the number of follicles ≥ 11 mm and the level of E₂ on the day of hCG administration were known were included in the analyses.

Participants/Materials, Setting, Methods

The threshold for OHSS prediction of moderate and severe OHSS was assessed in women treated with corifollitropin alfa or daily recombinant follicle stimulation hormone (rFSH) in a gonadotropin-releasing hormone (GnRH)-antagonist protocol. Receiver operating characteristics curve analyses for moderate to severe OHSS and severe OHSS were performed on the combined dataset and the sensitivity and specificity for the optimal threshold of number of follicles ≥ 11 mm, E₂ levels on the day of (hCG), and a combination of both, were determined.

Main Results and the Role of Chance

The optimal threshold of follicles ≥ 11 mm on the day of hCG to identify those at risk of moderate to severe OHSS was 19 (sensitivity and specificity 62.3% and 75.6%, respectively) and for severe OHSS was also 19 (sensitivity and specificity 74.3% and 75.3%, respectively). The positive and negative predictive values were 6.9% and 98.6%, respectively, for moderate to severe OHSS, and 4.2% and 99.5% for severe OHSS.

Limitations, Reasons for Caution

This was a retrospective analysis of combined data from three trials following ovarian stimulation with two different gonadotropins.

Wider Implications of the Findings

For patients with 19 follicles or more ≥11 mm on the day of hCG, measures to prevent the development of OHSS should be considered. Secondary preventive measures include cycle cancellation or coasting, use of a GnRH agonist to trigger final oocyte maturation in place of hCG and a freeze all strategy.

Trial Registration

ClinicalTrials.gov NCT00702845

NCT00696800

NCT00696878

In Vitro Maturation in Women with vs. without Polycystic Ovarian Syndrome: A Systematic Review and Meta-Analysis

Objective

To evaluate in vitro maturation (IVM) in sub-fertile women with polycystic ovarian syndrome (PCOS) undergoing in vitro fertilisation (IVF), by comparing outcomes with a control group of non-PCOS.

Study design

A search strategy was developed for PubMed and studies reporting rates of the following outcomes (live birth; clinical pregnancy; implantation; cycle cancellation; oocyte maturation; oocyte fertilization; miscarriage) between patients with PCOS, PCO and controls undergoing IVM were deemed eligible. The review was conducted in accordance to the PRISMA guidelines and included studies quality was assessed through the Newcastle-Ottawa Quality scale. ORs with their corresponding 95% CIs were calculated for the main analysis and subgroup analyses were performed for PCOS cases vs. controls and PCOS vs. PCO cases. Alternative analyses were performed for live birth and clinical pregnancy, based on cycles and on women. Subgroup analyses for FSH stimulation, hCG priming and type of procedure (IVF/ICSI) were undertaken for all meta-analyses encompassing at least four study arms. Random effects models were used to calculate pooled effect estimates.

Results

Eleven studies were identified. A total of 268 PCOS patients (328 cycles), 100 PCO patients (110 cycles) and 440 controls (480 cycles) were included in the meta-analysis. A borderline trend towards higher birth rates among PCOS patients emerged (pooled OR = 1.74, 95%CI: 0.99–3.04) mainly reflected at the subgroup analysis vs. controls. Clinical pregnancy (pooled OR = 2.37, 95%CI: 1.53–3.68) and implantation rates (pooled OR = 1.73, 95%CI: 1.06–2.81) were higher, while cancellation rates lower (pooled OR = 0.18, 95%CI: 0.06-0.47) among PCOS vs. non-PCOS subjects; maturation and miscarriage rates did not differ between groups, while a borderline trend towards lower fertilization rates among PCOS patients was observed.

Conclusion

The present meta-analysis provides preliminary evidence on the effectiveness of IVM as a treatment option when offered in sub-fertile PCOS women, as the latter present at least as high outcome rates as those in non-PCOS.

Ultrasound guidance during embryo transfer: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

To summarize the current evidence on the effect of using ultrasound (US) guidance during embryo transfer (ET).

METHODS

In this systematic review, we included randomized controlled trials examining the effect of the use of US guidance during ET; data from studies using the same catheter type in study arms were not pooled with the results from studies that used different catheter types.

RESULTS

Twenty-one studies were included in the quantitative analysis: 18 compared 'US guidance' with 'clinical touch', of which one was subsequently excluded from the quantitative meta-analysis owing to a lack of available data, three studies compared transvaginal US guidance with transabdominal US guidance, and one study compared 'hysterosonometry before ET' with US guidance. Comparison of the use of US guidance with clinical touch, in studies that used the same catheter type in the study arms, indicated a benefit of using US guidance during ET on the rates of live birth (relative risk (RR), 1.48 (95% CI, 1.16-1.87)), based on two studies involving 888 women with moderate-quality evidence, and on the rates of clinical pregnancy (RR, 1.32 (95% CI, 1.18-1.46)), based on 13 studies involving 3641 women with high-quality evidence. However, when comparing the use of US guidance with clinical touch in studies that used different catheter types, the results suggest that using US guidance during ET has no effect on the rates of reproductive outcome: live birth (RR, 0.99 (95% CI, 0.83-1.19)), based on one study involving 1649 women with moderate-quality evidence; clinical pregnancy (RR, 1.04 (95% CI, 0.89-1.21)), based on five studies involving 2949 women with moderate-quality evidence. The estimates for the rate of miscarriage and for the other identified comparisons were imprecise.

CONCLUSIONS

The available evidence suggests that there is a benefit of using US guidance during ET. However, both US-guided transfer and clinical touch should be considered acceptable, as the benefit of US is not large and should be balanced against the increased cost and need to change the catheter type. More studies are required before conclusions can be drawn regarding the effect of other techniques on reproductive outcome.

Efficacy of the Levonorgestrel-Releasing Intrauterine System on IVF-ET Outcomes in PCOS With Simple Endometrial Hyperplasia

OBJECTIVE

This study investigated the in vitro fertilization (IVF) outcome of levonorgestrel-releasing intrauterine system (LNG-IUS) pretreatment for simple endometrial hyperplasia (EH) in patients with polycystic ovary syndrome (PCOS) undergoing IVF embryo transfer (IVF-ET).

METHODS

One hundred ninety patients with PCOS and simple EH without cytologic atypia were allocated randomly to 2 independent arms, that is, the LNG-IUS group (90 patients) and the non-LNG-IUS group (100 patients). Four hundred fourteen patients with PCOS without endometrial disease comprised the control group. Each patient was reevaluated by transvaginal ultrasonography (TVS) and endometrial biopsy after 6 months. For each patient, IVF outcome measures, such as number of recombinant follicle-stimulating hormone, endometrial thickness on human chorionic gonadotropin (HCG) day, hormone levels (progesterone, luetinizing hormone, and serum estradiol) on HCG day, number of oocytes, fertilization rate, clinical pregnancy rate, and miscarriage rate were compared among the 3 groups.

RESULTS

In general, the 3 groups did not differ with respect to the main clinical and biochemical data. After 6 months, patients in LNG-IUS group had an EH resolution rate of 87.77%. In the non-LNG-IUS group, the resolution rate was 15.00%, and 3% of these patients showed progression of EH. The clinical pregnancy rates in the non-LNG-IUS group were significantly lower (28.04%) than that in the LNG-IUS group (46.06%) and the control group (44.65%). The miscarriage rate was highest in the non-LNG-IUS group, but no significant difference in miscarriage rate existed among the 3 groups.

CONCLUSION

The study illustrates that the LNG-IUS can be safely used for 6 months as a treatment for patients with PCOS and simple EH. Additionally, use of the LNG-IUS can increase the clinical pregnancy rates and implantation rates of patients with PCOS and simple EH who undergo gonadotropin-releasing hormone agonist IVF-ET protocols.