Meiotic maturation failure in primary ovarian insufficiency: insights from a bovine model.

PURPOSE: Oocytes from women presenting primary ovarian insufficiency (POI) generate viable embryos at a lower rate than non-POI women, but the mechanisms responsible for the lower oocyte quality remain elusive. Due to the scarcity of human oocytes for research, animal models provide a promising way forward. We aimed at investigating the molecular events characterizing final maturation in POI oocytes in a well-defined POI-like bovine model. METHODS: Single-cell RNA-sequencing of bovine control and POI-like, GV, and MII oocytes (n = 5 per group) was performed. DEseq2 was used to identify differentially expressed genes. Further, a Gene set enrichment analysis and a transcriptomic meta-analysis between bovine and human oocytes were performed. RESULTS: In control cows, we found 2223 differentially expressed genes between the GV and MII stages. Specifically, the affected genes were related to RNA processing and transport, protein synthesis, organelle remodeling and reorganization, and metabolism. The meta-analysis with a set of young human oocytes at different maturation stages revealed 315 conserved genes through the GV-MII transition in cows and humans, mostly related to meiotic progression and cell cycle. Gene expression analysis between GV and MII of POI-like oocytes showed no differences in terms of differentially expressed genes, pointing towards a substantial failure to properly remodel the transcriptome in the POI model, and with the clustering analysis indicating that the cow's genetic background had a higher impact than the oocyte's maturation stage. CONCLUSION: Overall, we have identified and characterized a valuable animal model of POI, paving the way to identifying new molecular mechanisms involved in POI.

An ESHG-ESHRE survey on the current practice of expanded carrier screening in medically assisted reproduction.

STUDY QUESTION: What is the current practice and views on (expanded) carrier screening ((E)CS) among healthcare professionals in medically assisted reproductive (MAR) practices in Europe? SUMMARY ANSWER: The findings show a limited support for ECS with less than half of the respondents affiliated to centres offering ECS, and substantial variation in practice between centres in Europe. WHAT IS KNOWN ALREADY: The availability of next-generation sequencing, which enables testing for large groups of genes simultaneously, has facilitated the introduction and expansion of ECS strategies, currently offered particularly in the private sector in the context of assisted reproduction. STUDY DESIGN, SIZE, DURATION: A cross-sectional survey evaluating practice and current views among professionals working in MAR practice in different European countries was designed using the online SurveyMonkey tool. The web-based questionnaire included questions on general information regarding the current practice of (E)CS in MAR and questions on what is offered, to whom the test is offered, and how it is offered. It consisted mostly of multiple-choice questions with comment boxes, but also included open questions on the respondents' attitudes/concerns relevant to (E)CS practice, and room to upload requested files (e.g. guidelines and gene panels). In total, 338 responses were collected from 8 February 2022 to 11 April 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: The online survey was launched with an invitation email from the ESHRE central office (n = 4889 emails delivered) and the European Society of Human Genetics (ESHG) central office (n = 1790 emails delivered) sent to the ESHRE and ESHG members, and by social media posts. The survey was addressed to European MAR centres or gamete banks and to centres located in non-European countries participating in the European IVF-monitoring Consortium. Two reminder emails were sent. After exclusion of 39 incomplete responses received (e.g. only background information), 299 respondents from 40 different countries were included for analyses. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, 42.5% (127/299) of respondents were affiliated to centres offering ECS. The perceived responsibility to enable prospective parents to make informed reproductive decisions and preventing suffering/burden for parents were the main reasons to offer ECS. A single ECS panel is offered by nearly 45% (39/87 received answers) of the centres offering ECS, 25.3% (22/87) of those centres offer a selection of ECS panels, and 29.9% (26/87) offer whole exome sequencing and a large in silico panel. Different ranges of panel sizes and conditions were included in the ECS panel(s) offered. Most of the respondents (81.8%; 72/88 received answers) indicated that the panels they offer are universal and target the entire population. Pathogenic variants (89.7%; 70/78 received answers), and to a lesser extent, likely pathogenic variants (64.1%%; 50/78 received answers), were included in the ECS report for individuals and couples undergoing MAR with their own gametes. According to 87.9% (80/91 received answers) of the respondents, patients have to pay to undergo an ECS test. Most respondents (76.2%; 61/80 received answers) reported that counselling is provided before and after the ECS test. Preimplantation genetic testing, the use of donor gametes, and prenatal diagnostic testing were the three main reproductive options discussed with identified carrier couples. The main reason, according to the respondents, for not offering ECS in their centre, was the lack of professional recommendations supporting ECS (52.5%; 73/139 received answers) and the high cost for couples or reimbursement not being available (49.6%; 69/139). The challenges and moral dilemmas encountered by the respondents revolved mainly around the content of the offer, including the variants classification and the heterogeneity of the panels, the counselling, and the cost of the test. LIMITATIONS, REASONS FOR CAUTION: Although the total number of respondents was acceptable, the completion rate of the survey was suboptimal. In addition, the heterogeneity of answers to open-ended questions and the ambiguity of some of the answers, along with incomplete responses, posed a challenge in interpreting survey results. It is also plausible that some questions were not easily understood by the respondents. For this reason, response and non-response bias are acknowledged as further limitations of the survey. WIDER IMPLICATIONS OF THE FINDINGS: The results of this survey could aid in identifying potential challenges or areas for improvement in the current practice of ECS in the MAR field and contribute to the discussion on how to address them. The results underline the need to stimulate a more knowledge-based debate on the complexity and the pros and cons of a possible implementation of ECS in MAR. STUDY FUNDING/COMPETING INTEREST(S): All costs relating to the development process were covered from European Society of Human Reproduction and Embryology and European Society of Human Genetics funds. There was no external funding of the development process or manuscript production. A.C. is full-time employee of Juno Genetics. L.H. declared receiving a research grant during the past 36 months from the Netherlands Organisation for Health Research and Development. She has also participated in a Health Council report of the Netherlands on preconception carrier screening and collaborated with the VSOP Dutch Genetic Alliance (patient umbrella organization on rare and genetic disorders). L.H. and C.v.E. are affiliated with Amsterdam University Medical Centre, a hospital that offers ECS in a non-commercial setting. R.V. received honoraria for presentations from Merck Academy and is unpaid board member of the executive committee of the Spanish Fertility Society. The other authors had nothing to disclose. TRIAL REGISTRATION NUMBER: N/A.

Single-cell proteomics reveals decreased abundance of proteostasis and meiosis proteins in advanced maternal age oocytes.

Advanced maternal age is associated with a decline in oocyte quality, which often leads to reproductive failure in humans. However, the mechanisms behind this age-related decline remain unclear. To gain insights into this phenomenon, we applied plexDIA, a multiplexed data-independent acquisition, single-cell mass spectrometry method, to analyze the proteome of oocytes from both young women and women of advanced maternal age. Our findings primarily revealed distinct proteomic profiles between immature fully grown germinal vesicle and mature metaphase II oocytes. Importantly, we further show that a woman's age is associated with changes in her oocyte proteome. Specifically, when compared to oocytes obtained from young women, advanced maternal age oocytes exhibited lower levels of the proteasome and TRiC complex, as well as other key regulators of proteostasis and meiosis. This suggests that aging adversely affects the proteostasis and meiosis networks in human oocytes. The proteins identified in this study hold potential as targets for improving oocyte quality and may guide future studies into the molecular processes underlying oocyte aging.

No association between LH levels and ovarian response in oocyte donors triggered with gonadotropin-releasing hormone agonist: A prospective study.

OBJECTIVE: Are circulating luteinizing hormone (LH) levels predictive of ovarian response in oocyte donors triggered with gonadotropin-releasing hormone (GnRH) agonists? STUDY DESIGN: A prospective cohort study with 224 oocyte donation cycles between 2021 and 2022 at a single center, examined the relationship between circulating luteinizing hormone (LH) levels and ovarian response. Oocyte donors underwent GnRH antagonist downregulation followed by GnRH agonist trigger. LH, estradiol, and progesterone levels were measured on day one of stimulation, trigger-day and 12 h post-trigger. Oocyte retrieval and maturity rates were analyzed using univariate and multivariate analyses, and the correlation between post-trigger LH levels and outcomes was assessed by Pearson's correlation test. A significance level of p < 0.05 was used. RESULTS: Mean age was 26 ± 4.3 years, mean body mass index (BMI, kg/m2) was 22.6 ± 3.2 and mean antral follicle count (AFC) was 21.7 ± 8.2. Post-trigger LH levels averaged 51.3 IU/L (SD 34.8), and oocyte retrieval rate and maturity rates were 112,7% (+/-48,1%) and 77,8% (+/- 17,2%), respectively. No significant differences were found in these outcomes for donors with post-trigger LH values below and above 15 IU/L (Mann Whitney's p > 0.05). However, exploratory analyses revealed that post-trigger LH values < 22 IU/L and basal LH levels < 4 IU/L were associated with significantly lower oocyte retrieval rate (90 % vs 110 %, p = 0.019 and 100 % vs 110 %, p = 0.019, respectively). CONCLUSIONS: This study, a first in exclusively focusing on oocyte donors, did not support the previously reported LH value of 15 IU/L as predictive of suboptimal ovarian response. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT05109403.

Personalizing the first dose of FSH for IVF/ICSI patients through machine learning: a non-inferiority study protocol for a multi-center randomized controlled trial.

BACKGROUND: Adequately selecting the initial follicle-stimulating hormone (FSH) dose during controlled ovarian stimulation (COS) is key for success in assisted reproduction. The objective of COS is to obtain an optimal number of oocytes to increase the chances of achieving a pregnancy, while avoiding complications for the patient. Current clinical protocols do achieve good results for the majority of patients, but further refinements in individualized FSH dosing may reduce the risk of poor ovarian response while also limiting the risk of ovarian hyperstimulation syndrome (OHSS) risk. Models to select the first FSH dose in COS have been presented in literature with promising results. However, most have only been developed and tested in normo-ovulatory women under the age of 40 years. METHODS: This is a randomized, controlled, multicenter, single blinded, clinical trial. This study will be performed in 236 first cycle in vitro fertilization (IVF) and/or ICSI (intracytoplasmic sperm injection) patients, randomized 1:1 in two arms. In the intervention arm, the dose of FSH will be assigned by a machine learning (ML) model called IDoser, while in the control arm, the dose will be determined by the clinician following standard practice. Stratified block randomization will be carried out depending on the patient being classified as expected low responder, high responder, or normo-responder. Patients will complete their participation in the trial once the first embryo transfer result is known. The primary outcome of the study is the number of metaphase II (MII) oocytes retrieved at ovarian pick up (OPU) and the hypothesis of non-inferiority of the intervention arm compared to the control. Secondary outcomes include the number of cycle cancelations (due to low response or no retrieval of mature oocytes), risk of ovarian hyperstimulation syndrome (OHSS), and clinical pregnancy and live birth rates per first transfer. DISCUSSION: To our knowledge, this is the first randomized trial to test clinical performance of an all-patient inclusive model to select the first dose of FSH for COS. Prospective trials for machine learning (ML) models in healthcare are scarce but necessary for clinical application. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05948293 . Registered on 14 July 2023.

Implicit bias in diagnosing mosaicism amongst preimplantation genetic testing providers: results from a multicenter study of 36 395 blastocysts.

STUDY QUESTION: Does the diagnosis of mosaicism affect ploidy rates across different providers offering preimplantation genetic testing for aneuploidies (PGT-A)? SUMMARY ANSWER: Our analysis of 36 395 blastocyst biopsies across eight genetic testing laboratories revealed that euploidy rates were significantly higher in providers reporting low rates of mosaicism. WHAT IS KNOWN ALREADY: Diagnoses consistent with chromosomal mosaicism have emerged as a third category of possible embryo ploidy outcomes following PGT-A. However, in the era of mosaicism, embryo selection has become increasingly complex. Biological, technical, analytical, and clinical complexities in interpreting such results have led to substantial variability in mosaicism rates across PGT-A providers and clinics. Critically, it remains unknown whether these differences impact the number of euploid embryos available for transfer. Ultimately, this may significantly affect clinical outcomes, with important implications for PGT-A patients. STUDY DESIGN, SIZE, DURATION: In this international, multicenter cohort study, we reviewed 36 395 consecutive PGT-A results, obtained from 10 035 patients across 11 867 treatment cycles, conducted between October 2015 and October 2021. A total of 17 IVF centers, across eight PGT-A providers, five countries and three continents participated in the study. All blastocysts were tested using trophectoderm biopsy and next-generation sequencing. Both autologous and donation cycles were assessed. Cycles using preimplantation genetic testing for structural rearrangements were excluded from the analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: The PGT-A providers were randomly categorized (A to H). Providers B, C, D, E, F, G, and H all reported mosaicism, whereas Provider A reported embryos as either euploid or aneuploid. Ploidy rates were analyzed using multilevel mixed linear regression. Analyses were adjusted for maternal age, paternal age, oocyte source, number of embryos biopsied, day of biopsy, and PGT-A provider, as appropriate. We compared associations between genetic testing providers and PGT-A outcomes, including the number of chromosomally normal (euploid) embryos determined to be suitable for transfer. MAIN RESULTS AND THE ROLE OF CHANCE: The mean maternal age (±SD) across all providers was 36.2 (±5.2). Our findings reveal a strong association between PGT-A provider and the diagnosis of euploidy and mosaicism. Amongst the seven providers that reported mosaicism, the rates varied from 3.1% to 25.0%. After adjusting for confounders, we observed a significant difference in the likelihood of diagnosing mosaicism across providers (P < 0.001), ranging from 6.5% (95% CI: 5.2-7.4%) for Provider B to 35.6% (95% CI: 32.6-38.7%) for Provider E. Notably, adjusted euploidy rates were highest for providers that reported the lowest rates of mosaicism (Provider B: euploidy, 55.7% (95% CI: 54.1-57.4%), mosaicism, 6.5% (95% CI: 5.2-7.4%); Provider H: euploidy, 44.5% (95% CI: 43.6-45.4%), mosaicism, 9.9% (95% CI: 9.2-10.6%)); and Provider D: euploidy, 43.8% (95% CI: 39.2-48.4%), mosaicism, 11.0% (95% CI: 7.5-14.5%)). Moreover, the overall chance of having at least one euploid blastocyst available for transfer was significantly higher when mosaicism was not reported, when we compared Provider A to all other providers (OR = 1.30, 95% CI: 1.13-1.50). Differences in diagnosing and interpreting mosaic results across PGT-A laboratories raise further concerns regarding the accuracy and relevance of mosaicism predictions. While we confirmed equivalent clinical outcomes following the transfer of mosaic and euploid blastocysts, we found that a significant proportion of mosaic embryos are not used for IVF treatment. LIMITATIONS, REASONS FOR CAUTION: Due to the retrospective nature of the study, associations can be ascertained, however, causality cannot be established. Certain parameters such as blastocyst grade were not available in the dataset. Furthermore, certain platform-related and clinic-specific factors may not be readily quantifiable or explicitly captured in our dataset. As such, a full elucidation of all potential confounders accounting for variability may not be possible. WIDER IMPLICATIONS OF THE FINDINGS: Our findings highlight the strong need for standardization and quality assurance in the industry. The decision not to transfer mosaic embryos may ultimately reduce the chance of success of a PGT-A cycle by limiting the pool of available embryos. Until we can be certain that mosaic diagnoses accurately reflect biological variability, reporting mosaicism warrants utmost caution. A prudent approach is imperative, as it may determine the difference between success or failure for some patients. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Torres Quevedo Grant, awarded to M.P. (PTQ2019-010494) by the Spanish State Research Agency, Ministry of Science and Innovation, Spain. M.P., L.B., A.R.L., A.L.R.d.C.L., N.P.P., M.P., D.S., F.A., A.P., B.M., L.D., F.V.M., D.S., M.R., E.P.d.l.B., A.R., and R.V. have no competing interests to declare. B.L., R.M., and J.A.O. are full time employees of IB Biotech, the genetics company of the Instituto Bernabeu group, which performs preimplantation genetic testing. M.G. is a full time employee of Novagen, the genetics company of Cegyr, which performs preimplantation genetic testing. TRIAL REGISTRATION NUMBER: N/A.

Moonshots and last miles: what it may take to treat infertility for all.

Innovation in medically assisted reproduction (MAR) is at an all-time high, with new technologies being developed for the laboratory and around the patient experience, and deployed quickly and effectively. Nevertheless, substantial improvements in the success of infertility care seem to elude the field. This article presents the view that MAR is missing the key innovation motor of mechanistic knowledge, which historically relates to a lack of public resources of the kind afforded to other diseases. It is posited that unless and until we raise infertility at the level of an urgent unmet medical need in the eyes of government and national funding body, innovation will be limited in scope and impact, and be incremental in nature.

The expression levels of NOS2, HMOX1, and VEGFC in cumulus cells are markers of oocyte maturation and fertilization rate.

Throughout the reproductive life of women, cumulus cells (CC) protect the dormant oocyte from damage, act as sensors of the follicular microenvironment, and act as a gatekeeper for oocyte developmental potential. One such mechanism relies on the hypoxia-tolerance response, which, with age, decreases systematically, including in the ovary. We aimed to evaluate the association between gene expression related to hypoxia and aging in CC and reproductive results in in vitro fertilization cycles. We recruited 94 women undergoing controlled ovarian stimulation. Total RNA was extracted from pooled CCs collected after oocyte pick-up (OPU) and reverse-transcribed to complementary DNA using random hexamers to test 14 genes related to hypoxia response via HIF1α activation, oxidative stress, and angiogenic responses. The expression of CLU, NOS2, and TXNIP had a positive correlation with age (rs = 0.25, rs = 0.24, and rs = 0.35, respectively). Additionally, NOS2 and HMOX1 expression correlated positively with the retrieval of immature oocytes (rs = 0.22 and rs = 0.40, respectively). Moreover, VEGFC levels decreased overall with increasing fertilization rate, independently of age (rs = -0.29). We found that the fertilization potential of a cohort of oocytes is related to the ability of CC to respond to oxidative stress and hypoxia with age, pointing at NOS2, HMOX1, and VEGFC expression as markers for oocyte maturation and fertilization success.

Long-term storage of vitrified oocytes does not affect pregnancy and live birth rates: analysis of 5362 oocyte donation cycles.

RESEARCH QUESTION: Does long-term storage of vitrified oocytes affect laboratory and reproductive outcomes after intracytoplasmic sperm injection? DESIGN: Retrospective cohort study including 41,783 vitrified-warmed oocytes from 5362 oocyte donation cycles between 2013 and 2021. Five categories of storage time were established to analyse its effect on clinical and reproductive outcomes (≤1 year [reference group], 1-2 years, 2-3 years, 3-4 years and >4 years). RESULTS: The mean number of warmed oocytes was 8.0 ± 2.5 oocytes. Oocyte storage time ranged from 3 days to 8.2 years (mean: 0.7 ± 0.9). Mean oocyte survival (90.2% ± 14.7% overall) did not significantly decrease with longer storage time after adjusting for confounders (88.9% for time >4 years, P = 0.963). A linear regression model did not show a significant effect of oocyte storage time on fertilization rate (about 70% in all time categories) (P > 0.05). Reproductive outcomes after the first embryo transfer were statistically comparable across storage times (P > 0.05 for all categories). Longer term oocyte storage (>4 years) did not affect the chances of clinical pregnancy (OR 0.700, 95% CI 0.423 to 1.158, P = 0.2214) or live birth (OR 0.716, 95% CI 0.425 to 1.208, P = 0.2670). CONCLUSIONS: Oocyte survival, fertilization rate, pregnancy and live birth rates are not affected by the time spent by vitrified oocytes in vapour-phase nitrogen tanks.

Specific processing of meiosis-related transcript is linked to final maturation in human oocytes.

Human meiosis in oocytes entails an intricate regulation of the transcriptome to support late oocyte growth and early embryo development, both crucial to reproductive success. Currently, little is known about the co- and post-transcriptional mRNA processing mechanisms regulating the last meiotic phases, which contribute to transcriptome complexity and influence translation rates. We analyzed gene expression changes, splicing and pre-mRNA processing in an RNA sequencing set of 40 human oocytes at different meiotic maturation stages, matured both in vivo and in vitro. We found abundant untranslated region (UTR) processing, mostly at the 3' end, of meiosis-related genes between the germinal vesicle (GV) and metaphase II (MII) stages, supported by the differential expression of spliceosome and pre-mRNA processing related genes. Importantly, we found very few differences among GV oocytes across several durations of IVM, as long as they did not reach MII, suggesting an association of RNA processing and successful meiosis transit. Changes in protein isoforms are minor, although specific and consistent for genes involved in chromosome organization and spindle assembly. In conclusion, we reveal a dynamic transcript remodeling during human female meiosis, and show how pre-mRNA processing, specifically 3'UTR shortening, drives a selective translational regulation of transcripts necessary to reach final meiotic maturation.

Exonic genetic variants associated with unexpected fertilization failure and zygotic arrest after ICSI: a systematic review.

Fertilization failure (FF) and zygotic arrest after ICSI have a huge effect on both patients and clinicians, but both problems are usually unexpected and cannot be properly diagnosed. Fortunately, in recent years, gene sequencing has allowed the identification of multiple genetic variants underlying failed ICSI outcomes, but the use of this approach is still far from routine in the fertility clinic. In this systematic review, the genetic variants associated with FF, abnormal fertilization and/or zygotic arrest after ICSI are compiled and analyzed. Forty-seven studies were included. Data from 141 patients carrying 121 genetic variants affecting 16 genes were recorded and analyzed. In total, 27 variants in PLCZ1 (in 50 men) and 26 variants in WEE2 (in 24 women) are two of the factors related to oocyte activation failure that could explain a high percentage of male-related and female-related FF. Additional variants identified were reported in WBP2NL, ACTL9, ACTLA7, and DNAH17 (in men), and TUBB8, PATL2, TLE6, PADI6, TRIP13, BGT4, NLRP5, NLRP7, CDC20 and ZAR1 (in women). Most of these variants are pathogenic or potentially pathogenic (89/121, 72.9%), as demonstrated by experimental and/or in silico approaches. Most individuals carried bi-allelic variants (89/141, 63.1%), but pathogenic variants in heterozygosity have been identified for PLCZ1 and TUBB8. Clinical treatment options for affected individuals, such as chemical-assisted oocyte activation (AOA) or PLCZ1 cRNA injection in the oocyte, are still experimental. In conclusion, a genetic study of known pathogenic variants may help in diagnosing recurrent FF and zygotic arrest and guide patient counselling and future research perspectives.

No difference in morphokinetics between male and female preimplantation embryos from ART.

RESEARCH QUESTION: Do morphokinetic parameters vary between male and female preimplantation embryos? DESIGN: This was a retrospective cohort study of 175 cycles between March 2018 and June 2021 at two reproductive centres. It included time-lapse data from 92 female and 83 male preimplantation embryos exclusively issued from fresh oocyte donation and undergoing intracytoplasmic sperm injection (ICSI). Only fresh elective single-embryo transfers on day 5 were assessed, and the sex of the embryo was confirmed at birth. The morphokinetic parameters analysed were measured in hours post-insemination (hpi). A two-tailed Student's t-test was used to compare the morphokinetics between embryo sexes and a value of P < 0.05 was considered statistically significant. RESULTS: Following strict inclusion criteria to avoid poor-quality preimplantation embryos, no significant differences were found in morphokinetic parameters when comparing cycles that resulted in female versus male live births for the following: time to pronuclear fading (22.1 ± 2.4 versus 22.4 ± 2.9 hpi; P = 0.52); time to the 2-cell stage (24.6 ± 2.5 versus 25.0 ± 2.5 hpi; P = 0.34); time to the 3-cell stage (35.3 ± 3.3 versus 35.8 ± 3.1 hpi; P = 0.28); time to the 4-cell stage (36.3 ± 3.4 versus 36.9 ± 3.7 hpi; P = 0.20); time to the 5-cell stage (47.9 ± 4.6 versus 48.0 ± 4.8 hpi; P = 0.88); time to the 8-cell stage (54.0 ± 6.5 versus 54.1 ± 6.5 hpi; P = 0.91); time to the start of blastulation (86.3 ± 14.6 versus 85.7 ± 15.5 hpi; P = 0.78); and time to the full blastocyst stage (93.0 ± 16.9 versus 93.2 ± 17.2 hpi; P = 0.94). CONCLUSIONS: There are no significant differences in morphokinetics between male and female preimplantation embryos.

Supporting first FSH dosage for ovarian stimulation with machine learning.

RESEARCH QUESTION: Is it possible to identify accurately the optimal first dose of FSH in ovarian stimulation by means of a machine learning model? DESIGN: Observational study (2011-2021) including first IVF cycles with own oocytes. A total of 2713 patients from five private reproductive centres were included in the development phase (2011-2019) and 774 in the validation phase (2020-2021). Predictor variables included age, BMI, AMH, AFC and previous live births. Performance was measured with a proposed score based on the number of MII oocytes retrieved and dose received, recommended, or both. RESULTS: The included cycles were from women aged 37.7 ± 4.4 years (18-45 years), with a BMI of 23.5 ± 4.2 kg/m2, AMH of 2.4 ± 2.3 ng/ml, AFC of 11.3 ± 7.6, and an average number of MII obtained 6.9 ± 5.4. The model reached a mean performance score of 0.87 (95% CI 0.86 to 0.88) in the development phase, significantly better than for doses prescribed by clinicians for the same patients (0.83, 95% CI 0.82 to 0.84; P = 2.44 e-10). Mean performance score of the model recommendations was 0.89 (95% CI 0.88 to 0.90) in the validation phase, also significantly better than clinicians (0.84, 95% CI 0.82 to 0.86; P = 3.81 e-05). The model was shown to surpass the performance of standard practice. CONCLUSION: This machine learning model could be used as a training and learning tool for new clinicians, and as quality control for experienced clinicians.

Tailored support may reduce mental and relational impact of infertility on infertile patients and partners.

RESEARCH QUESTION: What is the psychological impact of infertility on infertile patients and partners of infertile patients? DESIGN: This online, international, quantitative survey assessed the impact of infertility on mental health, relationships and daily activities for 1944 respondents. Respondents were male or female infertile patients (n = 1037) or partners to infertile patients (n = 907; not necessarily partners of the patient sample) and were recruited at different stages of the treatment journey. RESULTS: The most common emotions were 'sadness' at infertility diagnosis and 'anxiety' during treatment. Emotions differed in nature and intensity throughout the journey. Envy of others who achieved pregnancy was frequently reported by women. More than half of respondents (60.4%; n = 1174) perceived the infertility journey to have impacted their mental health, and 44.1% (n = 857) of respondents sought mental health support. More patients reported mental health impacts (70.1%, n = 727) than partners (49.3%, n = 447). One in three respondents indicated that their relationship had suffered due to the infertility diagnosis. Of these respondents, 55.0% (n = 409) strongly agreed that infertility caused an emotional strain. Patients more often than partners reported a detrimental impact on daily activities. Respondents most commonly agreed with statements regarding an 'effect on work-life balance'. CONCLUSION: Treatment journey stages are defined by their impact profile, which differs between infertile patients and partners of infertile patients. Negative impacts are diverse (mental health, relational, daily activities). There was disparity between the number of respondents reporting mental health issues and the number seeking mental health support. This indicates the need for support services tailored to different treatment stages.

How long can the sperm wait? Effect of incubation time on ICSI outcomes.

In sperm processing for IVF/ICSI incubation times differ considerably both between and within assisted reproduction facilities. There is no established consensus on the optimal sperm incubation timings to maximize pregnancy rates, and the few studies addressing this association rely on manual and operator-dependent methods for time recording. The present retrospective cohort study includes 1169 ICSI cycles using fresh semen processed by swim-up. An operator-independent, radiofrequency-based system was used to record sperm incubation times: from sample collection to swim-up (T1, 0.35 ± 0.26); from swim-up to ICSI (T2, 3.30 ± 2.2); and total time from sample collection to ICSI (T, 3.66 ± 2.26). In oocyte donation cycles, we observed a significant negative effect of T1 on fertilization rate (FR; generalized linear modelling regression, coeff. -0.20, p = 0.001); however, after analysing all times by deciles and by adjusted logistic regression, none of the time intervals had a significant effect on pregnancy (biochemical, clinical, and ongoing) and live birth (LB) rates (p > 0.05 for all outcomes). In cycles using the patient's oocytes, we observed a negative effect of T2 (ordinal regression, coeff. -0.25, p = 0.011) and T (-0.33, p = 0.005) on the mean morphological score of the embryo cohort. In these cycles, a trend associating longer values of T with higher LB rates was identified (OR = 1.47, p = 0.050), although this difference is likely not clinically significant. In conclusion, while longer sperm incubation in vitro may impact slightly both FRs and embryo morphology after ICSI, no adverse effects were detected on the reproductive outcomes.

Barriers and factors associated with significant delays to initial consultation and treatment for infertile patients and partners of infertile patients.

RESEARCH QUESTION: What are the key drivers and barriers for infertile patients and their partners to see an infertility specialist and initiate treatment? DESIGN: An online, international, 30-minute quantitative survey collected data from 1944 respondents from nine countries. Respondents were infertile patients (n = 1037) or partners of infertile patients (n = 907; but not necessarily partners of the patient sample), at different stages of the treatment journey. RESULTS: The overall average times were 3.2 years to receiving a medical infertility diagnosis, 2.0 years attempting to achieve pregnancy without assistance before treatment, and 1.6 years of treatment before successful respondents achieved pregnancy. The most common driver for considering treatment after a consultation (n = 1025) was an equal desire within the couple to have a child (40.8%). Of the partners (n = 356), 29.8% reported that transparency of information from healthcare professionals about treatment expectations was important. A significantly higher proportion of respondents seeking treatment reported that healthcare professionals offered supportive services (61.2%) and mental health services (62.0%), than of the 207 respondents who did not seek treatment (32.4% and 36.7%, respectively; P < 0.001). Perceived cost was the most commonly reported barrier for respondents not seeking a consultation (37.5% of n = 352) or treatment (42.0% of n = 207). Of the 95 respondents who discontinued treatment, 34.7% discontinued due to the financial impact. CONCLUSIONS: Respondents reported significant delays to seeking treatment, probably negatively impacting the chances of achieving pregnancy. Motivational coherence within couples was a key driver and cost of treatment was the main barrier. Reported supportive service offerings by healthcare professionals were significantly associated with continuation of the treatment journey.

The human sperm basal body is a complex centrosome important for embryo preimplantation development.

The mechanism of conversion of the human sperm basal body to a centrosome after fertilization, and its role in supporting human early embryogenesis, has not been directly addressed so far. Using proteomics and immunofluorescence studies, we show here that the human zygote inherits a basal body enriched with centrosomal proteins from the sperm, establishing the first functional centrosome of the new organism. Injection of human sperm tails containing the basal body into human oocytes followed by parthenogenetic activation, showed that the centrosome contributes to the robustness of the early cell divisions, increasing the probability of parthenotes reaching the compaction stage. In the absence of the sperm-derived centrosome, pericentriolar material (PCM) components stored in the oocyte can form de novo structures after genome activation, suggesting a tight PCM expression control in zygotes. Our results reveal that the sperm basal body is a complex organelle which converts to a centrosome after fertilization, ensuring the early steps of embryogenesis and successful compaction. However, more experiments are needed to elucidate the exact molecular mechanisms of centrosome inheritance in humans.

Human oocyte meiotic maturation is associated with a specific profile of alternatively spliced transcript isoforms.

The transition from a transcriptionally active state (GV) to a transcriptionally inactive state (mature MII oocytes) is required for the acquisition of oocyte developmental competence. We hypothesize that the expression of specific genes at the in vivo matured (MII) stage could be modulated by posttranscriptional mechanisms, particularly regulation of alternative splicing (AS). In this study, we examined the transcriptional activity of GV oocytes after ovarian stimulation followed by oocyte pick-up and the landscape of alternatively spliced isoforms in human MII oocytes. Individual oocytes were processed and analyzed for transcriptional activity (GV), gene expression (GV and MII), and AS signatures (GV and MII) on HTA 2.0 microarrays. Samples were grouped according to maturation stage, and then subgrouped according to women's age and antral follicular count (AFC); array results were validated by quantitative polymerase chain reaction. Differentially expressed genes between GV and MII oocytes clustered mainly in biological processes related to mitochondrial metabolism. Interestingly, 16 genes that were related to the regulation of transcription and mitochondrial translation showed differences in alternatively spliced isoform profiles despite not being differentially expressed between groups. Altogether, our results contribute to our understanding of the role of AS in oocyte developmental competence acquisition.

Reproductive Outcomes in Lesbian Couples Undergoing Reception of Oocytes from Partner Versus Autologous In Vitro Fertilization/Intracytoplasmic Sperm Injection.

Purpose: This study aimed to compare reproductive outcomes after Reception of Oocytes from Partner (ROPA; also called reciprocal in vitro fertilization) with those after in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) with autologous oocytes, in lesbian couples. Methods: This was a retrospective matched cohort study of couples performing a first cycle of either ROPA (n = 60) or autologous IVF/ICSI (n = 120) between February 2012 and May 2018. Couples were matched 1:2 by age of the oocyte provider, day of embryo transfer (ET), and number of embryos transferred. Pregnancy and live birth rates after the first ET and cumulative results after all subsequent ETs performed until June 2019 were evaluated. Results: Reproductive outcomes were significantly better after ROPA at first ET: biochemical pregnancy 70.0% versus 47.5% (p = 0.004), clinical pregnancy 60.0% versus 40.0% (p = 0.011), ongoing pregnancy 60.0% versus 36.7% (p = 0.003), and live birth 57.1% versus 29.8% (p = 0.001). After adjusting for age, body mass index, and number of mature oocytes, we still observed a significant improvement across all outcomes in ROPA (live birth rate odds ratio [OR]: 3.05, 95% confidence interval [CI] 1.42-6.57). Cumulative pregnancy and live birth rates were also higher after ROPA (live birth 66.1% vs. 43.4% [p = 0.005]). The adjusted analysis result for cumulative live birth was OR: 2.51, 95% CI: 1.14-5.54. Conclusion: When medically indicated, ROPA can potentially improve reproductive outcomes for lesbian couples through the possibility of selecting the best combination between two oocyte providers and two gestational mothers, provided that both women wish to participate in the pregnancy plan.