Growth development of French children born after in vitro maturation

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

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

Maternal and neonatal outcome and children's development after medically assisted reproduction with in-vitro matured oocytes-a systematic review and meta-analysis

BACKGROUND

IVM was implemented in medically assisted reproduction 25 years ago. IVM does not involve controlled ovarian stimulation (COS) and is mainly indicated in patients with a high risk of ovarian hyperstimulation syndrome, in particular in patients with polycystic ovary syndrome (PCOS); it is also an acknowledged option in fertility protection. However, the in-vitro culture of immature oocytes raises concerns over their developmental potential and the putative impact on children's health. Although an increasing number of studies on obstetric and neonatal outcomes of IVM children and their development have been published in recent years, study designs are difficult to compare, since IVM is used in women with various indications and IVM protocols do not follow the same standards.

OBJECTIVE AND RATIONALE

The aim of this systematic review was to evaluate the current evidence from IVM children of an impact of in-vitro culture of immature oocytes. Primary outcome parameters were birthweight and children's development up to the age of 2 years. We also compared pregnancy pathologies and the outcome of IVM children and COS children in relation to maternal indications, in particular PCOS, and to the type of IVM protocols with or without ovulation trigger as the secondary outcome parameters. IVM is an accepted clinical option for many centres; however, a comprehensive analysis of the available data is needed to establish whether the use of human oocytes that are fully matured in vitro is safe for both children and their mothers.

SEARCH METHODS

Google Scholar and PubMed were used for identifying peer-reviewed original articles and reviews through January 2020. A total of 191 studies were screened and 16 studies were included in the qualitative synthesis. Studies were stratified according to indications, the use of an ovulation trigger and multiplicity.

OUTCOMES

Birthweights of IVM singletons and multiples were comparable to their respective COS controls: birthweights were also similar if the analysis was restricted to mothers with PCOS. IVM children had a comparable birthweight to COS children, irrespective of whether an ovulation trigger was used in IVM cycles or not. The frequency of gestational diabetes (GD) in singleton pregnancies was comparable between IVM and COS, regardless of infertility background. There was also no difference in GD frequency between IVM and COS, if an hCG ovulation trigger in IVM cycles was used or not. Hypertensive disorders in singleton pregnancies of women with PCOS were significantly more frequent after IVM compared to COS, in particular if IVM cycles were performed only with in-vitro matured oocytes. There was no difference in the preterm birth rate of singleton pregnancies between IVM and COS. Preterm birth rates were still similar if only women diagnosed with PCOS were compared and whether an ovulation trigger in IVM was used or not. The malformation rate in IVM children did not differ in COS children versus children after natural conception. At the age of 2 years, IVM singletons showed similar anthropometric and mental development compared to COS children or children from natural conception.

WIDER IMPLICATIONS

The higher incidence of hypertensive disorders in IVM pregnancies needs monitoring during pregnancy. Current data on the development of IVM children are encouraging, although the quality of many studies is limited and long-term data beyond 2 years are scarce. Further studies should be based on generally accepted IVM protocols. Studies on long-term outcomes beyond 2 years are needed to search for potential long-time sequelae of IVM.

Growth and other health outcomes of 2-year-old singletons born after IVM versus controlled ovarian stimulation in mothers with polycystic ovary syndrome

STUDY QUESTION

Does In vitro maturation (IVM) of immature oocytes affect health, including growth at 2 years of age, in singletons born to mothers with polycystic ovary syndrome (PCOS)?

SUMMARY ANSWER

This study of 92 singletons born after IVM in mothers with PCOS showed no significant differences in anthropometry and health outcome parameters in comparison with a cohort of 74 peers born after intracytoplasmic sperm injection (ICSI) and conventional controlled ovarian stimulation (COS) in mothers with PCOS.

WHAT IS KNOWN ALREADY

IVM has been used worldwide in women with PCOS. However, the paucity of available data related to children's health following IVM is an important impediment to a more widespread use of the technology. Although previous reports on the neonatal outcome after IVM are generally reassuring, these studies have flaws that hamper the interpretation of outcomes. Moreover, few studies have reported on health outcomes after IVM beyond infancy, and particularly growth data in children born after IVM of immature oocytes from mothers with PCOS are lacking.

STUDY DESIGN SIZE DURATION

This single-center cohort study compared anthropometry and health outcomes in 92 singletons born after ICSI of in vitro matured oocytes with 74 singletons born after ICSI without IVM (COS). All participants were born to mothers who were diagnosed with PCOS phenotype A, B, C or D and reached the age of 2 years between November 2012 and June 2019. Singletons born after COS were randomly selected for follow-up until young adulthood.

PARTICIPANTS/MATERIALS SETTING METHODS

Anthropometric parameters and health status data were prospectively collected at birth, 4 months and 2 years in cohorts of singletons followed since birth. Results were adjusted for neonatal (birthweight z-score, birth order), treatment (day of transfer, number of embryos transferred, mode of transfer) and parental (maternal smoking, age, body mass index (BMI), anti-Müllerian hormone level, PCOS phenotype, gestational diabetes, hypertensive disorder and paternal BMI) characteristics.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, no differences were found for bodyweight, height and head circumference z-score between IVM and COS children at birth, at 4 months or at 2 years (all P > 0.05). In addition, z-scores of waist and mid-upper arm circumference at 2 years were comparable in IVM and COS children. Adjustment for covariates did not change the conclusion. Surgical intervention rate as well as the hospital admission rate were comparable between the IVM and COS group (all P > 0.05). The proportion of children born to mothers with metabolically unfavorable PCOS phenotypes (A and C) was comparable in the two groups (52.1% in IVM and 45.9% in COS). Mothers giving birth to a child conceived using IVM were younger than mothers in the COS group but their BMI was comparable.

LIMITATIONS REASONS FOR CAUTION

Although our study describes the largest cohort to date of singletons born after IVM applied in mothers with well-defined PCOS phenotypes, the current sample size only allowed us to detect moderate differences in anthropometry. Also, follow-up of children born after IVM for indications other than PCOS, for example fertililty preservation after cancer diagnosis, is highly recommended.

WIDER IMPLICATIONS OF THE FINDINGS

We did not observe adverse effects of IVM on growth parameters in offspring ~2 years of age compared to COS, but future studies should focus on cardiovascular and metabolic outcomes in these children and adolescents given their mother's PCOS condition.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by Methusalem grants and by grants from Wetenschappelijk Fonds Willy Gepts; all issued by the Vrije Universiteit Brussel (VUB). All co-authors, except M.B., M.D.V. and H.T. declared no conflict of interest. M.B. has received consultancy fees from MSD, Serono Symposia and Merck. M.D.V. has received fees for lectures from MSD, Ferring, Gedeon Richter and Cook Medical. H.T. has received consultancy fees from Gedeon Richter, Merck, Ferring, Abbott and ObsEva. The Universitair Ziekenhuis Brussel (UZ Brussel) and the Center for Medical Genetics have received several educational grants from IBSA, Ferring, MSD and Merck for establishing the database for follow-up research and organizing the data collection.

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.

Obstetrical, neonatal, and long-term outcomes of children conceived from in vitro matured oocytes

OBJECTIVE

To investigate the obstetrical, neonatal, and long-term outcomes of in vitro maturation (IVM) compared with conventional in vitro fertilization (IVF) in women with polycystic ovarian syndrome (PCOS).

DESIGN

Matched retrospective case-control study.

SETTING

University fertility clinic.

PATIENT(S)

One hundred eighty-four patients undergoing IVM were compared with 366 patients undergoing conventional IVF. All had PCOS and were matched for patient age, gestational age at birth, and the number of fetuses.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Obstetrics, neonatal outcomes, and childhood medical problems and development.

RESULT(S)

Women's mean age at oocytes retrieval was 32.6 ± 2.9 years. Children's mean age was 7.5 ± 2.3 years. There were no differences in the frequency of obstetrical and neonatal outcomes between the two groups. No difference was found in birth weights between the two groups. The incidence of congenital anomalies was similar between the groups (4.3% in IVM group vs. 4.1% in IVF group). No significant difference was observed between the two groups in the frequency and duration of hospitalization during childhood. Growth developmental status of both groups was within normal range.

CONCLUSION(S)

In a matched setting between IVM and IVF babies born from women with PCOS, no significant increased risk associated with IVM was been identified after a mean follow-up of 7.5 years.

In Vitro Maturation of Oocytes in Women at Risk of Ovarian Hyperstimulation Syndrome-A Prospective Multicenter Cohort Study

BACKGROUND

In vitro maturation (IVM) is an artificial reproductive technology in which immature oocytes are harvested from the ovaries and subsequently will be matured in vitro. IVM does not require ovarian hyperstimulation (OH) and thus the risk of ovarian hyperstimulation syndrome (OHSS) is avoided. In this study, we assessed the live birth rate per initiated IVM cycle in women eligible for in vitro fertilization/intracytoplasmic sperm injection (IVF/ ICSI) and at risk for OHSS. Furthermore, we followed women who were not pregnant after IVM and committed to a conventional IVF/ICSI procedure.

MATERIALS AND METHODS

In this multicenter prospective cohort study, we started 76 IVM cycles using recombinant follicle stimulating hormone (rFSH) priming in 68 patients. There were 66 oocyte retrievals, in which a total of 628 oocytes were collected. We incubated the immature oocytes for 24-48 hours and fertilized those that reached metaphase II by ICSI.

RESULTS

Three hundred eighty six (61% oocytes) achieved metaphase II. The fertilization rate was 55%. We performed 59 embryo transfers (1.9 embryos per transfer) in 56 women, including 3 frozen embryo transfers. There were four ongoing pregnancies (5.3% per initiated cycle) leading to the birth of a healthy child at term. None of the patients developed OHSS. The ongoing pregnancy rate of the first conventional IVF/ICSI cycle after an unsuccessful IVM cycle was 44%, which was unexpectedly high.

CONCLUSION

We concluded that IVM led to live births but with low effectiveness in our study. Earlier reported IVM success rates are higher which can be caused by a more extended experience in these centers with the intricate laboratory process. However, a possible selection bias in these studies cannot be ruled out. Furthermore, IVM might have a beneficial effect on further IVF/ICSI treatments due to its "ovarian drilling" effect.

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.

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.

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.

Cardiovascular and metabolic profiles of offspring conceived by assisted reproductive technologies: a systematic review and meta-analysis

OBJECTIVE

To evaluate cardiovascular and metabolic features of offspring conceived by in vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI).

DESIGN

Literature review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Offspring from IVF-ICSI versus natural conception.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Systolic and diastolic blood pressure (SBP and DBP), cardiovascular function, body mass index (BMI), and lipid and glucose profiles.

RESULT(S)

We included 19 studies that had recruited 2,112 IVF-ICSI and 4,096 naturally conceived offspring, ranging from childhood to early adulthood. The blood pressure levels of IVF-ICSI offspring were statistically significantly higher than those of naturally conceived offspring (weighted mean differences and confidence intervals: 1.88 mm Hg [95% CI, 0.27, 3.49] for SBP and 1.51 mm Hg [95% CI, 0.33, 2.70] for DBP). In addition, cardiac diastolic function was suboptimal and vessel thickness was higher among IVF-ICSI offspring. Compared with the metabolism of naturally conceived offspring, IVF-ICSI offspring displayed comparable BMI, lower low-density lipoprotein cholesterol levels, and higher fasting insulin levels.

CONCLUSION(S)

Children conceived by IVF-ICSI manifested a minor yet statistically significant increase in blood pressure without the clustering of increased BMI or impaired lipid metabolism by early adulthood. Our findings indicate a risk of cardiovascular disease among IVF-ICSI offspring, which calls for longer-term follow-ups and further investigation.

In vitro maturation of oocytes is not associated with altered deoxyribonucleic acid methylation patterns in children from in vitro fertilization or intracytoplasmic sperm injection

OBJECTIVE

To study the possible transmission, to the next generation, of epigenetic defects associated with in vitro maturation (IVM) of human oocytes.

DESIGN

Case-control study using epigenetic data.

SETTING

Two collaborating university departments.

PATIENT(S)

Eleven IVM newborns and 19 controls, conceived by conventional assisted reproduction.

INTERVENTION(S)

Chorionic villus and cord-blood sampling.

MAIN OUTCOME MEASURE(S)

Using bisulfite pyrosequencing, we have measured average methylation levels of 6 imprinted (LIT1, MEG, MEST, NESPas, PEG3, and SNRPN), 5 tumor-suppressor (APC, ATM, BRCA1, RAD51C, and TP53), 2 pluripotency (NANOG and OCT4), and 2 metabolic (LEP and NR3C1) genes, as well as 2 repetitive elements (ALU and LINE1) in 2 tissues of IVM and control neonates. Using deep bisulfite sequencing, we have determined methylation patterns of many individual DNA molecules to detect rare RAD51C epimutations (allele methylation errors).

RESULT(S)

No statistically significant impact was found of IVM on chorionic villus and cord-blood DNA methylation at the studied developmentally important genes and interspersed repeats. The RAD51C epimutation rate was low (0.5% ± 0.1%) in all analyzed samples.

CONCLUSION(S)

IVM-induced epigenetic changes in offspring, if any, are relatively small in magnitude and/or infrequent.