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

Gonadotropin upregulates intraovarian calpains-1 and -2 during ovarian follicular recruitment in the SD rat model

Calpain role has been shown in the cumulus cell-oocyte complexes and, corpus luteum. We investigated the association of calpains-1 and -2 in ovarian folliculogenesis using the Sprague-Dawley (SD) rat model and steroidogenesis in the human granulosa cells (hGCs). We induced PCOS in 42-day-old SD rats by letrozole oral gavage for 21 days. Premature ovarian failure (POF) was induced in 21-day-old SD rats by 4-vinylcyclohexene diepoxide (VCD). Ovulation and ovarian hyperstimulatory (OHS) syndrome were induced by pregnant mare gonadotropin (PMSG) + human chorionic gonadotropin (hCG) treatments in 21 days SD rats, respectively. Steroidogenesis is stimulated in human granulosa cells (hGCs) by forskolin and the response of 17-beta-estradiol (E2) on calpains expression was checked in hGCs. The protein expression by immunoblotting and activity by biochemical assay of calpains-1 and -2 showed an oscillating pattern in the ovarian cycle. PMSG-induced follicular recruitment showed upregulation of calpains-1 and -2, but with no change during ovarian function cessation (POF). Upregulated calpain-2 expression and calpain activity was found in the hCG +PMSG-induced ovulation. Letrozole-induced PCOS showed downregulation of calpain-1, but upregulation of calpain-2. PMSG+hCG-induced OHS led to the upregulation of calpain-1. Letrozole and metformin separately increased the expression level of calpains-1 and -2 in the hGCs during luteinization. In conclusion, the expression levels of calpains -1 and -2 are increased with ovarian follicular recruitment by PMSG and calpain-1 is decreased in the PCOS condition, and letrozole and metformin upregulate the expression of calpains-1 and -2 during luteinization in the hGCs possibly via E2 action.

EPAS1 expression contributes to maintenance of the primordial follicle pool in the mouse ovary

Oxygen availability can have profound effects on cell fate decisions and survival, in part by regulating expression of hypoxia-inducible factors (HIFs). In the ovary, HIF expression has been characterised in granulosa cells, however, any requirement in oocytes remains relatively undefined. Here we developed a Hif2a/Epas1 germline-specific knockout mouse line in which females were fertile, however produced 40% fewer pups than controls. No defects in follicle development were detected, and quality of MII oocytes was normal, as per assessments of viability, intracellular reactive oxygen species, and spindle parameters. However, a significant diminishment of the primordial follicle pool was evident in cKO females that was attributed to accelerated follicle loss from postnatal day 6 onwards, potentially via disruption of the autophagy pathway. These data demonstrate the importance of HIF signalling in oocytes, particularly at the primordial follicle stage, and lend to the importance of controlling oxygen tension in the development of in vitro growth and maturation approaches for assisted reproduction.

Clinical outcomes from ART in predicted hyperresponders: in vitro maturation of oocytes versus conventional ovarian stimulation for IVF/ICSI

STUDY QUESTION

Do ongoing pregnancy rates (OPRs) differ in predicted hyperresponders undergoing ART after IVM of oocytes compared with conventional ovarian stimulation (OS) for IVF/ICSI?

SUMMARY ANSWER

One cycle of IVM is non-inferior to one cycle of OS in women with serum anti-Müllerian hormone (AMH) levels ≥10 ng/ml.

WHAT IS KNOWN ALREADY

Women with high antral follicle count and elevated serum AMH levels, indicating an increased functional ovarian reserve, are prone to hyperresponse during ART treatment. To avoid iatrogenic complications of OS, IVM has been proposed as a mild-approach alternative treatment in predicted hyperresponders, including women with polycystic ovary syndrome (PCOS) who are eligible for ART. To date, inferior pregnancy rates from IVM compared to OS have hampered the uptake of IVM by ART clinics. However, it is unclear whether the efficiency gap between IVM and OS may differ depending on the extent of AMH elevation.

STUDY DESIGN, SIZE, DURATION

This study is a retrospective cohort analysis of clinical and laboratory data from the first completed highly purified hMG (HP-hMG) primed, non-hCG-triggered IVM or OS (FSH or HP-hMG stimulation in a GnRH antagonist protocol) cycle with ICSI in predicted hyperresponders ≤36 years of age at a tertiary referral university hospital. A total of 1707 cycles were included between January 2016 and June 2022.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Predicted hyperresponse was defined as a serum AMH level ≥3.25 ng/ml (Elecsys® AMH, Roche Diagnostics). The primary outcome was cumulative ongoing pregnancy rate assessed 10-11 weeks after embryo transfer (ET). The predefined non-inferiority limit was -10.0%. The analysis was adjusted for AMH strata. Time-to-pregnancy, defined as the number of ET cycles until ongoing pregnancy was achieved, was a secondary outcome. Statistical analysis was performed using a multivariable regression model controlling for potential confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

Data from 463 IVM cycles were compared with those from 1244 OS cycles. Women in the IVM group more often had a diagnosis of Rotterdam PCOS (434/463, 93.7%) compared to those undergoing OS (522/1193, 43.8%), were significantly younger (29.5 years versus 30.5 years, P ≤ 0.001), had a higher BMI (25.7 kg/m2 versus 25.1 kg/m2, P ≤ 0.01) and higher AMH (11.6 ng/ml versus 5.3 ng/ml, P ≤ 0.001). Although IVM cycles yielded more cumulus-oocyte complexes (COCs) (24.5 versus 15.0 COC, P ≤ 0.001), both groups had similar numbers of mature oocytes (metaphase II (MII)) (11.9 MII versus 10.6 MII, P = 0.9). In the entire cohort, non-adjusted cumulative OPR from IVM was significantly lower (198/463, 42.8%) compared to OS (794/1244, 63.8%), P ≤ 0.001. When analysing OPR across different serum AMH strata, cumulative OPR in both groups converged with increasing serum AMH, and OPR from IVM was non-inferior compared to OS from serum AMH levels >10 ng/ml onwards (113/221, 51.1% (IVM); 29/48, 60.4% (OS)). The number of ETs needed to reach an ongoing pregnancy was comparable in both the IVM and the OS group (1.6 versus 1.5 ET's, P = 0.44). Multivariable regression analysis adjusting for ART type, age, BMI, oocyte number, and PCOS phenotype showed that the number of COCs was the only parameter associated with OPR in predicted hyperresponders with a serum AMH >10 ng/ml.

LIMITATIONS, REASONS FOR CAUTION

These data should be interpreted with caution as the retrospective nature of the study holds the possibility of unmeasured confounding factors.

WIDER IMPLICATIONS OF THE FINDINGS

Among subfertile women who are eligible for ART, IVM, and OS resulted in comparable reproductive outcomes in a subset of women with a serum AMH ≥10 ng/ml. These findings should be corroborated by a randomised controlled trial (RCT) comparing both treatments in selected patients with elevated AMH.

STUDY FUNDING/COMPETING INTEREST(S)

There was no external funding for this study. P.D. has been consultant to Merck Healthcare KGaA (Darmstadt, Germany) from April 2021 till June 2023 and is a Merck employee (Medical Director, Global Medical Affairs Fertility) with Merck Healthcare KGAaA (Darmstadt, Germany) since July 2023. He declares honoraria for lecturing from Merck KGaA, MSD, Organon, and Ferring. The remaining authors declared no conflict of interest pertaining to this study.

TRIAL REGISTRATION NUMBER

N/A.

A fresh start for IVM: capacitating the oocyte for development using pre-IVM

BACKGROUND

While oocyte IVM is practiced sporadically it has not achieved widespread clinical practice globally. However, recently there have been some seminal advances in our understanding of basic aspects of oocyte biology and ovulation from animal studies that have led to novel approaches to IVM. A significant recent advance in IVM technology is the use of biphasic IVM approaches. These involve the collection of immature oocytes from small antral follicles from minimally stimulated patients/animals (without hCG-priming) and an ∼24 h pre-culture of oocytes in an advanced culture system ('pre-IVM') prior to IVM, followed by routine IVF procedures. If safe and efficacious, this novel procedure may stand to make a significant impact on human ART practices.

OBJECTIVE AND RATIONALE

The objectives of this review are to examine the major scientific advances in ovarian biology with a unique focus on the development of pre-IVM methodologies, to provide an insight into biphasic IVM procedures, and to report on outcomes from animal and clinical human data, including safety data. The potential future impact of biphasic IVM on ART practice is discussed.

SEARCH METHODS

Peer review original and review articles were selected from PubMed and Web of Science searches for this narrative review. Searches were performed using the following keywords: oocyte IVM, pre-IVM, biphasic IVM, CAPA-IVM, hCG-triggered/primed IVM, natural cycle IVF/M, ex-vivo IVM, OTO-IVM, oocyte maturation, meiotic competence, oocyte developmental competence, oocyte capacitation, follicle size, cumulus cell (CC), granulosa cell, COC, gap-junction communication, trans-zonal process, cAMP and IVM, cGMP and IVM, CNP and IVM, EGF-like peptide and IVM, minimal stimulation ART, PCOS.

OUTCOMES

Minimizing gonadotrophin use means IVM oocytes will be collected from small antral (pre-dominant) follicles containing oocytes that are still developing. Standard IVM yields suboptimal clinical outcomes using such oocytes, whereas pre-IVM aims to continue the oocyte's development ex vivo, prior to IVM. Pre-IVM achieves this by eliciting profound cellular changes in the oocyte's CCs, which continue to meet the oocyte's developmental needs during the pre-IVM phase. The literature contains 25 years of animal research on various pre-IVM and biphasic IVM procedures, which serves as a large knowledge base for new approaches to human IVM. A pre-IVM procedure based on c-type natriuretic peptide (named 'capacitation-IVM' (CAPA-IVM)) has undergone pre-clinical human safety and efficacy trials and its adoption into clinical practice resulted in healthy live birth rates not different from conventional IVF.

WIDER IMPLICATIONS

Over many decades, improvements in clinical IVM have been gradual and incremental but there has likely been a turning of the tide in the past few years, with landmark discoveries in animal oocyte biology finally making their way into clinical practice leading to improved outcomes for patients. Demonstration of favorable clinical results with CAPA-IVM, as the first clinically tested biphasic IVM system, has led to renewed interest in IVM as an alternative, low-intervention, low-cost, safe, patient-friendly ART approach, and especially for patients with PCOS. The same new approach is being used as part of fertility preservation in patients with cancer and holds promise for social oocyte freezing.

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.

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.

Cumulative live birth rate after oocyte in vitro maturation with a pre-maturation step in women with polycystic ovary syndrome or high antral follicle count

PURPOSE

This study evaluated the 24-month cumulative live birth rate (CLBR) for women with polycystic ovary syndrome (PCOS) or high antral follicle count (AFC) who underwent oocyte in vitro maturation (IVM) with pre-maturation step (CAPA-IVM).

METHODS

This multicenter, retrospective study was performed at IVFMD, My Duc Hospital, and IVFMD Phu Nhuan, My Duc Phu Nhuan Hospital from 1 January 2017 to 31 December 2019. All women with PCOS or high AFC treated with a CAPA-IVM cycle were included. Cumulative live birth was defined as at least one live birth resulting from the initiated CAPA-IVM cycle. Where a woman did not return for embryo transfer, outcomes were followed up until 24 months from the day of oocyte aspiration. Logistic regression was performed to identify factors predicting the CLBR.

RESULTS

Data from 374 women were analyzed, 368 of whom had embryos for transfer (98.4%), and six had no embryos for transfer (1.6%). The oocyte maturation rate was 63.2%. The median number of frozen embryos was 4 [quartile 1, 2; quartile 3, 6]. Cumulative clinical pregnancy and ongoing pregnancy rates were 60.4% and 43.6%, respectively. At 24 months after starting CAPA-IVM treatment, the CLBR was 38.5%. Multivariate analysis showed that patient age and number of frozen embryos were significant predictors of cumulative live birth after CAPA-IVM.

CONCLUSIONS

CAPA-IVM could be considered as an alternative to in vitro fertilization for the management of infertility in women with PCOS or a high AFC who require assisted reproductive technology.

Effectiveness, Flexibility and Safety of Switching IVF to IVM as a Rescue Strategy in Unexpected Poor Ovarian Response for PCOS Infertility Patients

BACKGROUND

According to the latest practice committee document, in vitro maturation (IVM) is a simple and safe procedure, especially in patients with polycystic ovary syndrome (PCOS). Does switching from in vitro fertilization (IVF) to IVM (IVF/M) help as a rescue infertility treatment for PCOS patients with an unexpected poor ovarian response (UPOR) tendency?

METHODS

This retrospective cohort study included 531 women with PCOS who had undergone 588 natural IVM cycles or had switched to IVF/M cycles from 2008 to 2017. Natural IVM was performed in 377 cycles, and switching IVF/M was performed in 211 cycles. The primary outcome measure was the cumulative live birth rates (cLBRs), and the secondary outcomes included laboratory and clinical outcomes, maternal safety, and obstetric and perinatal complications.

RESULTS

No significant difference was found in the cLBRs between the natural IVM and switching IVF/M groups (23.6% vs. 17.4%, p = 0.05). Meanwhile, the natural IVM group had a higher cumulative clinical pregnancy rate (36.0% vs. 26.0%, p = 0.01), and a decrease in the number of oocytes was obtained in the switching IVF/M group (13.5 vs. 12.0, p < 0.01). The number of good quality embryos in the natural IVM group was 2.2 ± 2.5, and 2.1 ± 2.3 (p = 0.64) in the switching IVF/M group. No statistically significant differences were observed in the number of 2 pronuclear (2PN) and available embryos. Ovarian hyperstimulation syndrome (OHSS) did not occur in the switching IVF/M and natural IVM groups, indicating a highly favorable outcome.

CONCLUSION

In PCOS infertile women with UPOR, timely switching IVF/M is a viable option that markedly reduces the canceled cycle, results in reasonable oocyte retrieval, and leads to live births.

Outcomes of clinical in vitro maturation programs for treating infertility in hyper responders: a systematic review

Oocyte in vitro maturation (IVM) has been proposed as an alternative to conventional ovarian stimulation (COS) in subfertile women with polycystic ovary syndrome. To evaluate the effectiveness and safety of IVM compared with COS in women with predicted hyperresponse to gonadotropins, we searched the published literature for relevant studies comparing any IVM protocol with any COS protocol followed by in vitro fertilization or intracytoplasmic sperm injection. A systematic review was undertaken on 3 eligible prospective studies. Live birth rate was not significantly lower after IVM vs. COS (odds ratio [95% confidence interval] of 0.56 [0.32-1.01] overall, 0.83 [0.63-1.10] for human chorionic gonadotropin (hCG)-triggered IVM [hCG-IVM] and 0.45 [0.18-1.13] for non-hCG-triggered IVM [non-hCG-IVM]), irrespective of the stage of transferred embryos. Data from nonrandomized studies generally showed either significantly low or statistically comparable rates of live birth with IVM vs. COS. Most studies have not identified any significant difference between IVM and COS with respect to the rates of obstetric or perinatal complications, apart from a potentially higher rate of hypertensive disorders during pregnancy. The development of offspring from IVM and COS with in vitro fertilization or intracytoplasmic sperm injection appears to be similar. Additional research is needed to identify which patient populations will benefit most from IVM, to define the appropriate clinical protocol, and to develop the optimal culture system.

In vitro egg maturation and in vitro fertilization-an idea whose time has come?

In vitro maturation of oocytes before their use in assisted reproduction has proved to be difficult and relatively unsuccessful despite a long history of attempts. Recent understanding of natural oocyte maturation, advances in culture media, and improved clinical approaches offer opportunities for a wider use of this technology in human in vitro fertilization.

Live birth is not the only relevant outcome in research assessing assisted reproductive technology

In assisted reproductive technology (ART) research, live birth has been generally accepted as an important outcome, if not the most important one. However, it has been reported inconsistently in the literature and solely focusing on live birth can lead to misinterpretation of research findings. In this review, we provide an overview on the definitions of live birth, including various denominators and numerators use. We present a series of real clinical examples in ART research to demonstrate the impact of variations in live birth on research findings and the importance of other outcomes, including multiple pregnancy, pregnancy loss, time to pregnancy leading to live birth, other short and long term maternal and offspring health outcomes and cost effectiveness measures. We suggest that outcome choices in ART research should be tailored for the research questions. A holistic outcome assessment beyond live birth would provide a full picture to address research questions in ART in terms of effectiveness and safety, and thus facilitate evidence-based decision making.

IVM of human immature oocytes for infertility treatment and fertility preservation

Background

Thousands of healthy babies are born from in vitro maturation (IVM) procedures, but the rate of efficiency differs with the source of immature oocytes obtained. Recently, there are different IVM protocols proposed for infertility treatment and fertility preservation.

Methods

Based on the literature, the clinical application for IVM of immature oocytes was summarized.

Main findings Results

Immature oocytes may be retrieved from women after priming with or without the use of follicular stimulation hormone (FSH), human chorionic gonadotrophin (hCG) or a combination of both FSH and hCG. Successful pregnancy rates with IVM technology seem to be correlated with the number of immature oocytes obtained. With the source and culture course of immature oocytes, there are various IVM protocols. IVM of immature oocytes is profoundly affected by the culture conditions, but no breakthrough has been made by improving the IVM medium itself. Thus, the clinical application of IVM technology continues to evolve.

Conclusion

IVM technology is a useful technique for infertile women and fertility preservation. Mild stimulation IVF combined with IVM of immature oocytes is a viable alternative to the conventional stimulation IVF cycle treatment as it may prove to be an optimal first-line treatment approach.

High pressure frozen oocytes have improved ultrastructure but reduced cleavage rates compared to conventionally fixed or vitrified oocytes

Context Live birth rates are lower for cryopreserved oocytes than for fresh IVF cycles, indicating a need for improved methodologies. Aims The aim of this study was to determine if high pressure freezing (HPF) could improve both ultrastructural preservation and cryopreserved oocyte quality when compared to conventional fixation and vitrification methods. Methods Sheep oocytes and embryos were prepared by HPF or vitrification, with or without cryoprotectants. Frozen oocytes were prepared for transmission electron microscopy or warmed, in vitro fertilised and the recovery and cleavage rates recorded. Key results Blastocyst rates were similar between fresh, HPF and vitrified embryos. HPF oocytes had improved ultrastructure compared to conventional fixation or vitrification, but had poorer survival and cleavage rates compared to vitrified oocytes. Freeze-substitution of cryopreserved oocytes and transmission electron microscopy demonstrated disruption of the oocyte ultrastructure in the presence of cryoprotectants. Conclusions Superior preservation of ultrastructure was observed in HPF oocytes compared to vitrification or conventional fixation methods. In the presence of CP, both embryos and oocytes could survive HPF and warming but oocytes had reduced development. Implications The HPF method has potential to be developed and lead to improved oocyte and embryo cryopreservation and outcomes for assisted reproduction.

Is early-follicular long-acting GnRH agonist protocol an alternative for patients with polycystic ovary syndrome undergoing in vitro fertilization?

BACKGROUND

We aimed to compare the clinical and perinatal outcomes of patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment with either an early-follicular long-acting gonadotropin-releasing hormone agonist (GnRH-a) long protocol (EFLL) or a midluteal short-acting GnRH-a long protocol (MLSL).

METHODS

This single-center, retrospective study, included patients with PCOS who underwent IVF/ICSI from January 2013 to June 2019 at the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China. Patients underwent either MLSL (1179 cycles) or EFLL (2390 cycles). The primary outcomes were pregnancy outcomes, perinatal and maternal complications.

RESULTS

Fresh embryo transfer (59.12% vs. 55.47%, P = 0.038), clinical pregnancy (75.23% vs. 53.82%, P = 0.001), and live birth rates (63.27% vs. 42.05%, P = 0.010) were higher in the EFLL group. However, the proportion of patients "freezing all" for high risk of ovarian hyperstimulation syndrome (OHSS) (24.27% vs. 32.06%, P = 0.001) and ectopic pregnancy (1.51% vs. 5.97%, P = 0.002) were lower in the EFLL group than in the MLSL group. The incidence of gestational diabetes was higher in the EFLL group than in the MLSL group (5.08% vs. 1.42%, RR 3.714, 95% confidence interval (CI) 1.474-9.360, P = 0.003). There were no significant differences in the incidence of hypertension, premature rupture of membranes, placenta previa, congenital heart disease, or neonatal weight between the two groups. Logistic regression results showed that age (OR 0.966, 95% CI 0.941-0.993, P = 0.013), treatments (OR 2.380, 95% CI 1.833-3.089, P = 0.001), and endometrial thickness on trigger day (OR 1.115, 95% CI 1.070-1.162, P = 0.001) were correlated with clinical pregnancy. Pre-pregnancy BMI (OR 1.098, 95% CI 1.002-1.204, P = 0.046), fasting plasma glucose (FPG) (OR 3.096, 95% CI 1.900-5.046, P = 0.001), and treatments (OR 3.458, 95% CI 1.359-8.800, P = 0.009) were correlated with gestational diabetes mellitus (GDM). Treatments (OR 0.291, 95% CI 0.148-0.575, P = 0.001) and endometrial thickness on trigger day (OR 0.834, 95% CI 0.722-0.962, P = 0.013) were correlated with ectopic pregnancy.

CONCLUSION

The early-follicular long-acting GnRH agonist long protocol can be used as an ideal assisted reproductive technology (ART) pregnancy assistance program for patients with PCOS, but obese patients should be encouraged to lose weight before ART treatments to reduce the risk of GDM.

Live birth after letrozole as an adjunct to follicle-stimulating hormone versus follicle-stimulating hormone alone for ovarian stimulation in in vitro fertilisation cycles-study protocol for a randomised controlled trial

INTRODUCTION

In vitro fertilisation (IVF) is an effective infertility treatment but the live birth rate remains unsatisfactory. Ovarian stimulation by follicle-stimulating hormone (FSH) is routinely used in IVF and the resulting high serum estradiol levels may impair oocyte/embryo quality and endometrial receptivity. Letrozole, an aromatase inhibitor, can reduce serum estradiol levels following ovarian stimulation. We aim to test the hypothesis that co-treatment with letrozole reduces supraphysiological serum estradiol levels and improves endometrial receptivity, leading to a higher live birth rate of IVF. We are conducting a randomised controlled trial (RCT) to evaluate whether letrozole as an adjunct to FSH in IVF is superior to FSH alone in the live birth rate of fresh embryo transfer.

METHODS/DESIGN

This is an open-label randomised controlled superiority trial being performed in two assisted reproduction centres in China. Infertile women who have antral follicle count (AFC) before ovarian stimulation or on day 5 of ovarian stimulation ≥15 are randomly allocated in a 1:1 ratio to receive either letrozole and FSH or FSH alone in a GnRH antagonist protocol. Recruited women follow the standard operating procedures of the two centres. The primary outcome is the live birth rate of the fresh embryo transfer. Stimulation parameters, maternal side effects and obstetric and perinatal complications are secondary outcomes. The planned sample size is 900, i.e. 450 per group.

DISCUSSION

The present study is the first multicentre randomised study to compare the live birth rate of the fresh embryo transfer following ovarian stimulation by letrozole and FSH versus FSH alone in women with anticipated high ovarian responses.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02912988 . Registered on September 23, 2016. This trial protocol is version 2.0.

Rescue in vitro maturation may increase the pregnancy outcomes among women undergoing intracytoplasmic sperm injection

INTRODUCTION

To investigate whether rescue in vitro maturation (R-IVM) improves the reproductive outcomes among women undergoing intracytoplasmic sperm injection (ICSI) after one oocyte retrieved cycle.

METHODS

Between January 2019 and December 2020, 2602 women who underwent ICSI in the Reproductive Medicine Center of Tongji Hospital, Wuhan, China, were included in our retrospective cohort study. There were 2112 women undergoing only ICSI and 490 women with R-IVM followed by ICSI. The intermediate reproductive outcomes and pregnancy outcomes were assessed, including the number of normally fertilized embryos, number of cleaved embryos, number of good-quality embryos, number of day-3 available embryos, number of embryos cultured past day-3, number of blastocysts, number of available blastocysts, biochemical pregnancy, miscarriage, clinical pregnancy and live birth. The perinatal outcomes were also assessed, including preterm birth and birth weight. The abovementioned outcomes were also calculated for in vivo matured and R-IVM oocytes separately in women undergoing ICSI with R-IVM group.

RESULTS

Compared with the women who underwent only ICSI, those who underwent ICSI with R-IVM had higher numbers of MII oocytes, normally fertilized embryos, cleaved embryos, day-3 available embryos, embryos cultured past day-3, and higher oocyte maturation rate, available embryo rate than women undergoing only ICSI. Additionally, we found that women undergoing ICSI with R-IVM had an increased chance of clinical pregnancy (adjusted OR=1.50, 95% CI: 1.17-1.93) and cumulative live birth (adjusted OR=1.35, 95% CI: 1.07-1.71). After propensity score matching (PSM), the cumulative live birth rate was 60.1% for women undergoing ICSI with R-IVM versus 54.9% for women undergoing only ICSI (OR=1.24, 95% CI: 0.94-1.63). The reproductive outcomes were also significantly different when calculated for in vivo matured and R-IVM oocytes separately in women undergoing ICSI with R-IVM group. All live births from R-IVM embryos were healthy and without malformations or complications.

CONCLUSION

R-IVM may improve the reproductive outcomes of women undergoing ICSI. It may also provide a reference for the safety of R-IVM. This study maybe support a routine application of R-IVM among patients who intend to undergo ICSI.