Use of cabergoline and post-collection GnRH antagonist administration for prevention of ovarian hyperstimulation syndrome

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.

The HERA (Hyper-response Risk Assessment) Delphi consensus for the management of hyper-responders in in vitro fertilization

PURPOSE

To provide agreed-upon guidelines on the management of a hyper-responsive patient undergoing ovarian stimulation (OS) METHODS: A literature search was performed regarding the management of hyper-response to OS for assisted reproductive technology. A scientific committee consisting of 4 experts discussed, amended, and selected the final statements. A priori, it was decided that consensus would be reached when ≥66% of the participants agreed, and ≤3 rounds would be used to obtain this consensus. A total of 28/31 experts responded (selected for global coverage), anonymous to each other.

RESULTS

A total of 26/28 statements reached consensus. The most relevant are summarized here. The target number of oocytes to be collected in a stimulation cycle for IVF in an anticipated hyper-responder is 15-19 (89.3% consensus). For a potential hyper-responder, it is preferable to achieve a hyper-response and freeze all than aim for a fresh transfer (71.4% consensus). GnRH agonists should be avoided for pituitary suppression in anticipated hyper-responders performing IVF (96.4% consensus). The preferred starting dose in the first IVF stimulation cycle of an anticipated hyper-responder of average weight is 150 IU/day (82.1% consensus). ICoasting in order to decrease the risk of OHSS should not be used (89.7% consensus). Metformin should be added before/during ovarian stimulation to anticipated hyper-responders only if the patient has PCOS and is insulin resistant (82.1% consensus). In the case of a hyper-response, a dopaminergic agent should be used only if hCG will be used as a trigger (including dual/double trigger) with or without a fresh transfer (67.9% consensus). After using a GnRH agonist trigger due to a perceived risk of OHSS, luteal phase rescue with hCG and an attempt of a fresh transfer is discouraged regardless of the number of oocytes collected (72.4% consensus). The choice of the FET protocol is not influenced by the fact that the patient is a hyper-responder (82.8% consensus). In the cases of freeze all due to OHSS risk, a FET cycle can be performed in the immediate first menstrual cycle (92.9% consensus).

CONCLUSION

These guidelines for the management of hyper-response can be useful for tailoring patient care and for harmonizing future research.

Women with PCOS who undergo IVF: a comprehensive review of therapeutic strategies for successful outcomes

Polycystic ovarian syndrome (PCOS) is a widespread syndrome that poses unique challenges and constraints to the field of assisted reproductive technology. This condition is the most common cause of anovulation among infertile couples. Debate exists over the best therapeutic course of action when patients with PCOS proceed to IVF. In this review, we evaluate the best-performing and safest methods of IVF preparation, ovarian stimulation, trigger method for maturation of stimulated egg growth, and planning for embryo transfer. Pre-IVF considerations include being aware of individual AMH and vitamin D levels as well as BMI prior to selecting an ovarian stimulation protocol. Numerous supplements such as myo-inositol complement the benefits of lifestyle change and may enhance IVF performance including oocyte yield and pregnancy rate. Concerning stimulation protocols, antagonist cycles with the judicious use of GnRH agonist trigger, pre-treatment with metformin and vitamin D repletion may help mitigate the accompanied risk of ovarian hyperstimulation syndrome (OHSS). Following ovarian stimulation, PCOS patients typically undergo programmed frozen embryo transfer (FET) cycles which are more conducive for women with irregular cycles, but likely carry a higher risk of hypertensive disorders of pregnancy. However, newer stimulated FET protocols using Letrozole may offer improved outcomes. Overall, patients with PCOS require careful individual tailoring of their IVF cycle to achieve optimal results.

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.

Gonadotropin releasing hormone (GnRH) antagonist administration to decrease the risk of ovarian hyperstimulation syndrome in GNRH agonist cycles triggered with human chorionic gonadotropin

PURPOSE

In Gonadotropin releasing hormone(GnRH) agonist IVF, after administration of human chorionic gonadotropin(HCG) triggering, there is a risk of ovarian hyperstimulation syndrome(OHSS). Few methods exist to prevent OHSS in these cases. Therefore, we investigated the use of a GnRH antagonist to decrease the risk of OHSS, due to its ability to decrease VEGF production and function.

METHOD

A retrospective cohort study of 171-IVF patients at risk for developing OHSS after a GnRH agonist cycle with HCG trigger was performed from 2011 to 2019. The patient population consisted of women with an unexpected exuberant response to stimulation based on ovarian reserve testing and were triggered with hCG. Women were converted to a freeze-all cycle and received either cabergoline 0.5 mg orally alone for 7 days from the collection(Group 1, n = 123) or received cabergoline 0.5 mg orally and ganirelix, 250 mcg SC for 7-10 days(Group 2, n = 48).

RESULTS

Group 1 had more cases of moderate and severe OHSS than group 2-(25% vs. 10% p = 0.03, and 52% vs. 25% p = 0.001 respectively). Group 1 reported more abdominal discomfort and bloating than group 2(91% vs. 65% p < 0.001) and the presence of free fluid was more frequent in group 1 than group 2(74% vs. 35% p < 0.001). Hemoconcentration and electrolyte disturbances were less severe in group 2 than in group 1 (p < 0.001 all cases).

CONCLUSION

In patients at high risk for developing OHSS after hCG trigger in a GnRH agonist cycle, the addition of GnRH antagonists in the luteal phase may reduce the risk of developing moderate and severe OHSS. The GnRH antagonist likely leads to more rapid luteolysis and down regulation of VEGF production and receptor response, thereby decreasing the hallmark increased vascular permeability.

Optimal individualization of patient-oriented ovarian stimulation in Japanese assisted reproductive technology clinics, a review for unique setting with advanced-age patients

Ovarian stimulation is a key issue in assisted reproductive technology (ART) treatment. ART practice in Japan is unique with various types of ovarian stimulation protocols, which may contribute to lower pregnancy rates compared to other countries. This review aims to clarify optimal individualized ovarian stimulation for improving the pregnancy rate per one oocyte retrieval cycle in Japan. We performed a literature review to describe ovarian stimulation, classification of infertile women depending on ovarian reserve and response, and Japanese ART data and discussed optimal conventional and mild ovarian stimulation protocols in Japan. According to Japanese ART registry data, the live birth rate of 30-35-year-old women was 32%-37% per ET cycle; therefore, four to five embryos are calculatedly needed when aiming a cumulative live birth rate of ≥80%. Mild stimulation aimed at collecting 5-10 oocytes can be alternative choice as an optimal ovarian stimulation protocol in young women. In 40-year-old women, the live birth rate is 18.8%, resulting in eight or more embryos as necessary. Conventional stimulation must be required in women with advanced age. In poor responders, however, mild stimulation may be sufficient for maximumly extracting their ovarian function. In Japan, mild ovarian stimulation can be selected in patients with a good prognosis and poor responders; however, conventional ovarian stimulation is necessary for women in advanced age.

Ovarian Hyperstimulation: Diagnosis, Prevention, and Management

Ovarian hyperstimulation syndrome (OHSS) is a severe complication of controlled ovarian stimulation (COS). Pathogenesis of the disease is based on massive transudation of protein-rich fluid from the vascular compartment into the peritoneal, pleural and pericardial spaces, with a variable picture of clinical manifestations depending on its severity. Nowadays OHSS can easily be avoided by several prevention methods, ranging from identification of high-risk patients, choice of a correct protocol stimulation, trigger with gonadotropin-releasing hormone (GnRH) agonists or, finally, the freeze-all strategy. When OHSS occurs, it can usually be managed as outpatient care. Only if severe/critical cases are diagnosed hospitalization is necessary for appropriate rehydration, monitoring of fluid balance and eventual drainage of ascitic fluid. One of the most dangerous complications of OHSS is venous thromboembolism (VTE). Thromboprophylaxis has shown to be cost effective and widely used, while there are controversies regarding the usage of low dose aspirin (LDA) as a preventive measure.

The freeze-all strategy after IVF: which indications?

The freeze-all strategy is gaining popularity worldwide as an alternative to the conventional fresh embryo transfer. It consists of cryopreservation of the entire embryo cohort and the embryo transfer in a subsequent cycle that takes place separately from ovarian stimulation. The freeze-all strategy was initially a 'rescue' strategy for women at high risk of ovarian hyperstimulation syndrome; however, this approach has been extended to other indications as a scheduled strategy to improve implantation rates. This assumes that ovarian stimulation can alter endometrial receptivity in fresh cycles owing to the effect of supraphysiological levels of steroids on endometrial maturation. The procedure, however, has not been associated with increased live birth rates in all infertile couples, and concerns have been raised about the occurrence of several adverse perinatal outcomes. It is, therefore, crucial to identify in which subgroups of patients a freeze-all strategy could be beneficial. The aim of this review is to summarize current scientific research in this field to highlight potential indications for this strategy and to guide clinicians in their daily practice.