Transcription factor-based transdifferentiation of human embryonic to trophoblast stem cells.

During the first week of development, human embryos form a blastocyst composed of an inner cell mass and trophectoderm (TE) cells, the latter of which are progenitors of placental trophoblast. Here, we investigated the expression of transcripts in the human TE from early to late blastocyst stages. We identified enrichment of the transcription factors GATA2, GATA3, TFAP2C and KLF5 and characterised their protein expression dynamics across TE development. By inducible overexpression and mRNA transfection, we determined that these factors, together with MYC, are sufficient to establish induced trophoblast stem cells (iTSCs) from primed human embryonic stem cells. These iTSCs self-renew and recapitulate morphological characteristics, gene expression profiles, and directed differentiation potential, similar to existing human TSCs. Systematic omission of each, or combinations of factors, revealed the crucial importance of GATA2 and GATA3 for iTSC transdifferentiation. Altogether, these findings provide insights into the transcription factor network that may be operational in the human TE and broaden the methods for establishing cellular models of early human placental progenitor cells, which may be useful in the future to model placental-associated diseases.

Impact of double trophectoderm biopsy on reproductive outcomes following single euploid blastocyst transfer.

OBJECTIVES: To study the effect of double trophectoderm biopsy on clinical outcomes following single euploid blastocyst transfer. STUDY DESIGN: Retrospective cohort study of 2046 single euploid frozen-thawed blastocyst transfers from January 2015 to June 2022 in a single centre. All patients undergoing a frozen-thawed embryo transfer (FTET) cycle with euploid blastocysts, biopsied for any indication, were included. The outcomes were compared for blastocysts which were biopsied and vitrified once (Group 1, n = 1684), biopsied once but vitrified twice (Group 2, n = 312) and biopsied and vitrified twice (Group 3n = 50). We adjusted for confounders and performed subgroup analysis for PGT-A, PGT-M and PGT-SR cycles. The primary outcome was live birth rate. Secondary outcomes included pregnancy, clinical pregnancy, birthweight and sex ratio. RESULTS: After adjusting for confounders (previous failed euploid implantations, embryo quality and day of biopsy), embryos which were biopsied twice had lower OR for clinical pregnancy (0.48, CI 0.26-0.88, p = 0.019) and for live birth (0.50 CI 0.27-0.92, p = 0.025) compared to controls. Embryos which were biopsied once but vitrified twice had no different ORs for all reproductive outcomes compared to controls. No significant difference was observed for neonatal birthweight or sex ratio amongst the three groups. This is a retrospective single centre study with inherent bias and results may not be transferable to all settings. CONCLUSION: This study is the largest to date assessing the outcomes of FTET cycles following double trophectoderm biopsy. The results are in keeping with the existing literature and can be incorporated into patient counselling. Whilst double biopsy seems to adversely impact LBR, it is only one of the many factors that can affect success rates. The subfertility background and embryo characteristics should not be overlooked. This study provides reassuring evidence since double biopsied embryos still result in live births with no difference in sex ratio or birthweight. However, long term follow up of the off-springs is lacking and should be reported in future studies.

Successful preimplantation genetic testing for fibrodysplasia ossificans progressiva: a case report.

PURPOSE OF THE STUDY: Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal dominant condition that leads to significant disability and morbidity, characterised by the formation of heterotopic hard tissues within connective tissues. The condition has an incidence of approximately one per two million people worldwide. There is no known single effective treatment available for FOP. We report the world's first case of a healthy infant born following in vitro fertilisation (IVF) and preimplantation genetic testing for monogenic disorder (PGT-M) using Karyomapping for FOP. CASE PRESENTATION: A 30-year-old Caucasian female with FOP presented with her partner seeking IVF with PGT-M to achieve a healthy pregnancy with an embryo unaffected by FOP. METHODS: The couple underwent IVF and PGT-M using Karyomapping as the testing method. A multi-disciplinary team approach was utilised in planning this case, considering the additional risks of oocyte retrieval, pregnancy and childbirth in women with FOP. MAIN FINDINGS: The oocyte retrieval was covered with a 5-day course of prednisolone to reduce the risk of a localised inflammatory reaction, which could result in subsequent heterotopic ossification. This was subsequently weaned down with reducing doses every two days. The patient underwent uncomplicated oocyte retrieval, yielding 12 mature oocytes. Following intracytoplasmic sperm injection (ICSI), ten zygotes having two pro-nuclei were cultured, and six underwent trophoectoderm biopsy and vitrification 5-6 days after retrieval. PGT-M via Karyomapping revealed four out of six (66.7%) of blastocysts were not carriers of the maternal high-risk FOP allele. In total, the patient had three separate embryo transfers. Pregnancy was achieved following the third frozen embryo transfer, which went to 37 weeks' gestation, and delivered by Caesarean section. The baby was born in excellent condition and is unaffected by FOP. CONCLUSION: IVF/ICSI and PGT-M using Karyomapping was successfully implemented to identify embryos carrying the high-risk FOP allele resulting in a healthy livebirth.

Integrating imaging-based classification and transcriptomics for quality assessment of human oocytes according to their reproductive efficiency.

PURPOSE: Utilising non-invasive imaging parameters to assess human oocyte fertilisation, development and implantation; and their influence on transcriptomic profiles. METHODS: A ranking tool was designed using imaging data from 957 metaphase II stage oocytes retrieved from 102 patients undergoing ART. Hoffman modulation contrast microscopy was conducted with an Olympus IX53 microscope. Images were acquired prior to ICSI and processed using ImageJ for optical density and grey-level co-occurrence matrices texture analysis. Single-cell RNA sequencing of twenty-three mature oocytes classified according to their competence was performed. RESULT(S): Overall fertilisation, blastulation and implantation rates were 73.0%, 62.6% and 50.8%, respectively. Three different algorithms were produced using binary logistic regression methods based on "optimal" quartiles, resulting in an accuracy of prediction of 76.6%, 67% and 80.7% for fertilisation, blastulation and implantation. Optical density, gradient, inverse difference moment (homogeneity) and entropy (structural complexity) were the parameters with highest predictive properties. The ranking tool showed high sensitivity (68.9-90.8%) but with limited specificity (26.5-62.5%) for outcome prediction. Furthermore, five differentially expressed genes were identified when comparing "good" versus "poor" competent oocytes. CONCLUSION(S): Imaging properties can be used as a tool to assess differences in the ooplasm and predict laboratory and clinical outcomes. Transcriptomic analysis suggested that oocytes with lower competence may have compromised cell cycle either by non-reparable DNA damage or insufficient ooplasmic maturation. Further development of algorithms based on image parameters is encouraged, with an increased balanced cohort and validated prospectively in multicentric studies.

Systematic review and meta-analysis: does pre-implantation genetic testing for aneuploidy at the blastocyst stage improve live birth rate?

PURPOSE: To establish if preimplantation genetic testing for aneuploidy (PGT-A) at the blastocyst stage improves the composite outcome of live birth rate and ongoing pregnancy rate per embryo transfer compared to conventional morphological assessment. METHODS: A systematic literature search was conducted using PubMed, EMBASE and Cochrane database from 1st March 2000 until 1st March 2022. Studies comparing reproductive outcomes following in vitro fertilisation using comprehensive chromosome screening (CCS) at the blastocyst stage with traditional morphological methods were evaluated. RESULTS: Of the 1307 citations identified, six randomised control trials (RCTs) and ten cohort studies fulfilled the inclusion criteria. The pooled data identified a benefit between PGT-A and control groups in the composite outcome of live birth rate and ongoing pregnancy per embryo transfer in both the RCT (RR 1.09, 95% CI 1.02-1.16) and cohort studies (RR 1.50, 95% CI 1.28-1.76). Euploid embryos identified by CCS were more likely to be successfully implanted amongst the RCT (RR 1.20, 95% CI 1.10-1.31) and cohort (RR 1.69, 95% CI 1.29-2.21) studies. The rate of miscarriage per clinical pregnancy is also significantly lower when CCS is implemented (RCT: RR 0.73, 95% CI 0.56-0.96 and cohort: RR 0.48, 95% CI 0.32-0.72). CONCLUSIONS: CCS-based PGT-A at the blastocyst biopsy stage increases the composite outcome of live births and ongoing pregnancies per embryo transfer and reduces the rate of miscarriage compared to morphological assessment alone. In view of the limited number of studies included and the variation in methodology between studies, future reviews and analyses are required to confirm these findings.

Reproductive outcomes from ten years of elective oocyte cryopreservation.

RESEARCH QUESTION: To assess the relationship between the number of oocytes retrieved during elective oocyte cryopreservation (EOC) cycles with various clinical, biochemical, and radiological markers, including age, body mass index (BMI), baseline anti-Müllerian hormone (AMH), antral follicle count (AFC), Oestradiol level (E2) and total number of follicles ≥ 12 mm on the day of trigger. To also report the reproductive outcomes from women who underwent EOC. METHODS: A retrospective cohort of 373 women embarking on EOC and autologous oocyte thaw cycles between 2008 and 2018 from a single London clinic in the United Kingdom. RESULTS: 483 stimulation cycles were undertaken amongst 373 women. The median (range) age at cryopreservation was 38 (26-47) years old. The median numbers of oocytes retrieved per cycle was 8 (0-37) and the median total oocytes cryopreserved per woman was 8 (0-45). BMI, E2 level and number of follicles ≥ 12 mm at trigger were all significant predictors of oocyte yield. Multivariate analysis confirmed there was no significant relationship between AFC or AMH, whilst on univariate analysis statistical significance was proven. Thirty six women returned to use their cryopreserved oocytes, of which there were 41 autologous oocyte thaw cycles undertaken. There were 12 successful livebirths achieved by 11 women. The overall livebirth rate was 26.8% per cycle. No livebirths were achieved in women who underwent EOC ≥ 40 years old, and 82% of all livebirths were achieved in women who had done so between 36 and 39 years old. CONCLUSION: Clinical, biochemical and radiological markers can predict oocyte yield in EOC cycles. Reproductive outcomes are more favourable when cryopreservation is performed before the age of 36, with lower success rates of livebirth observed in women aged 40 years and above.

Live birth rate following a euploid blastocyst transfer is not affected by double vitrification and warming at cleavage or blastocyst stage.

PURPOSE: To compare reproductive outcomes following a euploid embryo transfer, between those embryos vitrified-warmed twice to those vitrified-warmed once. METHODS: We retrospectively analysed 694 single euploid frozen embryo transfer cycles following preimplantation genetic testing for aneuploidy (PGT-A). For cycles in group 1 (N = 451), embryos were biopsied for PGT-A at blastocyst stage and vitrified. For cycles in group 2 (N = 146), embryos were vitrified at blastocyst stage, before being warmed and biopsied for PGT-A and vitrified again. For cycles in group 3 (N = 97), embryos were vitrified on day-3, before being warmed, cultured to day-5 and biopsied for PGT-A and re-vitrified. RESULTS: The pregnancy, clinical pregnancy and livebirth rate in group 2 were not statistically different to group 1 (pregnancy rate, adjusted OR 1.09, 95% CI 0.62-1.91; clinical pregnancy, aOR 0.89, 95% CI 0.58-1.37; live birth rate, aOR 0.85, 95% CI 0.56-1.28). There was also no significant difference between group 3 and group 1, with similar pregnancy rate (aOR 1.22, 95% CI 0.74-1.99), clinical pregnancy rate (aOR 1.21, 95% CI 0.75-1.96) and live birth rate (aOR 1.15, 95% CI, 0.73-1.80). There was no significant difference in miscarriage rates between all three groups. The age at the oocyte collection, embryo quality and day of biopsy were associated with pregnancy, clinical pregnancy and live birth rate. CONCLUSION: This study suggests that vitrifying and warming embryos twice at blastocyst or at cleavage and then blastocyst stage, can lead to similar reproductive outcomes to embryos vitrified-warmed once, after a single euploid embryo transfer.

Next Generation Sequencing Detects Premeiotic Errors in Human Oocytes.

Autosomal aneuploidy is the leading cause of embryonic and foetal death in humans. This arises mainly from errors in meiosis I or II of oogenesis. A largely ignored source of error stems from germinal mosaicism, which leads to premeiotic aneuploidy. Molecular cytogenetic studies employing metaphase fluorescence in situ hybridization and comparative genomic hybridisation suggest that premeiotic aneuploidy may affect 10-20% of oocytes overall. Such studies have been criticised on technical grounds. We report here an independent study carried out on unmanipulated oocytes that have been analysed using next generation sequencing (NGS). This study confirms that the incidence of premeiotic aneuploidy in an unselected series of oocytes exceeds 10%. A total of 140 oocytes donated by 42 women gave conclusive results; of these, 124 (88.5%) were euploid. Sixteen out of 140 (11.4%) provided evidence of premeiotic aneuploidy. Of the 140, 112 oocytes were immature (germinal vesicle or metaphase I), of which 10 were aneuploid (8.93%); the remaining 28 were intact metaphase II - first polar body complexes, and six of these were aneuploid (21.4%). Of the 16 aneuploid cells, half contained simple errors (one or two abnormal chromosomes) and half contained complex errors. We conclude that germinal mosaicism leading to premeiotic aneuploidy is a consistent finding affecting at least 10% of unselected oocytes from women undergoing egg collection for a variety of reasons. The importance of premeiotic aneuploidy lies in the fact that, for individual oocytes, it greatly increases the risk of an aneuploid mature oocyte irrespective of maternal age. As such, this may account for some cases of aneuploid conceptions in very young women.

The novel use of fertility quality of life (FertiQoL) treatment subscale to assess treatment acceptability in social egg freezing.

This is the first study to assess the impact of social egg freezing (SEF) on quality of life. This cross-sectional survey utilised the FertiQoL treatment module in women who underwent SEF between January 2008 and October 2019 (n = 94). The mean treatment score was 65.5, whereas the tolerability and environment scores were 62.4 and 68 respectively. Being married or in a relationship was associated with higher, albeit not statistically significant, scores (69.2) when compared to single women (66.3; p = 0.49). However, being separated or divorced was associated with significantly worse scores compared to married women, women in a relationship and single women (43.3 vs. 67.0; p = 0.001). There were no significant differences in scores between younger and older women, low and high number of oocytes stored, duration of stimulation cycles, or in those who had single or multiple cycles. These data suggest SEF is largely tolerable, with favourable FertiQoL scores compared to infertile women undergoing IVF. However, whilst such women are physiologically fertile, their situation renders them socially infertile. As such, women undergoing SEF should be identified as a population that requires additional support, who should be offered extensive counselling, active monitoring throughout the process and additional support if required.

Oocyte yield in social, medical and donor oocyte cryopreservation cycles.

To determine if oocyte yield in women undergoing cryopreservation for social (SOC), medical (MOC) and oocyte donation (OD) cycles is comparable when matched for age. 315 oocyte retrievals were performed for SOC, 116 for MOC and 392 for OD. Non-parametric Kruskal-Wallis tests and Poisson regression were used to assess the impact of age stratification. The median ages of women undergoing SOC, MOC, and OD were 38, 31 and 26 years respectively. The median (IQR) number of oocytes in the three categories was 7, 10, and 12. The oocyte yield was significantly higher in women aged 30-34 years undergoing SOC, compared to the MOC group. For the SOC group, age in years, oestradiol levels per 1000 pmol/and follicle count >12mm on the day of trigger were significant predictors of oocyte yield. Women embarking on SOC are significantly older than those undergoing MOC and OD, and thus oocyte yield is reduced when stratified for age. This study highlights the significant predictors of oocyte yield amongst women undergoing oocyte cryopreservation for specific indications. The findings can be used to optimise the yield and overall chance of successful livebirth.

Effectiveness of modified downregulation for women with moderate and severe adenomyosis of the uterus prior to frozen thawed embryo transfer (MODA) study protocol: a pragmatic randomised-controlled trial.

INTRODUCTION: Adenomyosis can adversely reduce chances of pregnancy in couples undergoing assisted conception. We aim to evaluate the effect of two different downregulation protocols on the reproductive outcomes in women with moderate and severe adenomyosis undergoing frozen-thawed embryo transfer (FTET). METHODS AND ANALYSIS: We will conduct a two-armed pragmatic randomised clinical trial comparing modified downregulation with gonadotrophin-releasing hormone (GnRH) analogue for 6 weeks to standard downregulation with GnRH analogue for 1 week prior to FTET. Our primary outcome is clinical pregnancy, defined as a viable intrauterine pregnancy confirmed by ultrasound at greater than 6 weeks gestation, with other secondary reproductive, neonatal and safety outcomes. We aim to randomise 162 patients over 3 years to achieve 80% power for detecting a 20% difference in the primary outcome at 5% significance. ETHICS AND DISSEMINATION: To date there is no consensus on the optimal protocol for management of subfertile women with adenomyosis. Modified downregulation could improve the clinical pregnancy rate by reducing the endometrial inflammatory reaction and/or myometrial contractility and their impact on uterine receptivity in women with moderate and severe adenomyosis of the uterus undergoing FTET. The MODA trial is designed to offer pragmatic, real-life evaluation of the optimal protocol for downregulation for this population during assisted conception treatments. Our findings will be published in peer-reviewed journals and presented at national and international scientific meetings and congresses. Ethical approval was granted by the NHS Research Ethics Committees (19/LO/1567). TRIAL REGISTRATION NUMBER: NCT03946722.

Paternal age over 50 years decreases assisted reproductive technology (ART) success: A single UK center retrospective analysis.

INTRODUCTION: To study whether paternal age exerts an effect, independent of maternal age, on the outcomes of fresh in vitro fertilization/ intracytoplasmic sperm injection (IVF/ICSI) cycles. Semen quality deteriorates with increasing paternal age; however, there is conflicting evidence for any impact paternal age may have on the outcome of IVF/ICSI. Several retrospective and prospective cohort studies have shown that paternal age increases the miscarriage rate and reduces the live birth rate. Some studies have shown no effect of paternal age on live birth rate or miscarriage rate. Studies involving donor oocytes have tended to show no independent effect of paternal age on assisted reproductive technology (ART) outcomes. The age at which paternal age may exert a significant deleterious effect on outcome is not known and there is no limit to paternal age in IVF/ICSI treatment. MATERIAL AND METHODS: A single-center retrospective cohort study was carried out at the Centre for Reproductive and Genetic Health, London, UK. Included in the analysis were all couples with primary or secondary infertility undergoing IVF/ICSI cycles in which the male partner produced a fresh semen sample and the cycle proceeded to fresh embryo transfer. All cycles of IVF/ICSI that used donor oocytes-donor sperm, frozen sperm, cycles leading to embryo storage and cycles including preimplantation genetic testing (PGT-A/PGT-M)-were excluded from analysis. The primary outcome was live birth rate and secondary outcomes were clinical pregnancy rate and miscarriage rate. Multivariate logistic regression analysis with live birth as a dependent variable and maternal and paternal age class as independent variables was performed. RESULTS: During the study period there were 4833 cycles, involving 4271 men, eligible for analysis; 1974/4833 (40.8%, 95% confiene intervals [CI] 39.5-42.2%) cycles resulted in a live birth. A significantly lower proportion of men over 51 years met World Health Organization semen analysis criteria (56/133, [42.1%, 95% CI 34.1-50.6]) compared with men under 51 years of age (2530/4138 [61.1%, 95% CI 60.0-62.6]) (p = 0.001). Both maternal and paternal age were retained in the multivariate model and for all maternal age subgroups the probability of live birth decreased with paternal age over 50 years (odds ratio [OR] 0.674, 95% CI 0.482-0.943) (p = 0.021). Paternal age over 50 years was not an independent predictor of miscarriage (OR 0.678, 95% CI 0.369-1.250) (p = 0.214). CONCLUSIONS: Paternal age over 50 significantly affects the chance of achieving a live birth following ART. Paternal age does not independently affect the risk of miscarriage following ART. There should be a public health message for men not to delay fatherhood.

Preimplantation Genetic Testing for Aneuploidy: Current Perspectives.

Despite improvements in assisted reproduction techniques (ARTs), live birth rates remain suboptimal, particularly in women with advanced maternal age (AMA). The leading cause of poor reproductive outcomes demonstrated in women with AMA, as well as women with recurrent miscarriage and repetitive implantation failure, is thought to be due to high rates of embryonic aneuploidy. Preimplantation genetic testing for aneuploidies (PGT-A) aims to select an euploid embryo for transfer and therefore improve ART outcomes. Early PGT-A studies using fluorescent in situ hybridization on mainly cleavage-stage biopsies failed to show improved delivery rates and, in certain cases, were even found to be harmful. However, the development of comprehensive chromosome screening, as well as improvements in culture media and vitrification techniques, has resulted in an emerging body of evidence in favor of PGT-A, demonstrating higher implantation, pregnancy, and live birth rates. While there are concerns regarding the potential harm of invasive biopsy and the cost implications of PGT-A, the introduction of noninvasive techniques and the development of new high-throughput methods which lower costs are tackling these issues. This review aims to assess the evidence for PGT-A, address possible concerns regarding PGT-A, and also explore the future direction of this technology.

Chromosomal Analysis of Cumulus Cells as a Future Predictor for Oocyte Aneuploidy: A Case Report.

BACKGROUND: Within the ovary, the optimal growth of the follicle, oocyte maturation and ovulation are highly conditioned by the two-way cross talk and interactions between the oocyte and the immediate somatic cells, known as cumulus cells (CCs). This biological communication between cell lines triggered the interest in the study of CCs as a biomarker of oocyte competence. CASE PRESENTATION: The findings of a 45,X mosaic pattern on CCs from a female patient with unremarkable medical history are reported in this study. The patient came to the Centre for Reproductive and Genetic Health, London on 14th August 2019 for her first visit and the follow up procedures were done for her to determine underlying genetic status. For this purpose, four sources of DNA including CCs, blood lymphocytes, buccal cells and immature oocytes were analyzed in the present report. CONCLUSION: In the present case study, the hypothesis of the female patient being mosaic 45,X was confirmed although the degree of mosaicism and whether this was affecting the germinal line could not be determined. In the event of the discovery of a cell line with an apparently abnormal genetic makeup, genetic counselling is important in order to understand the implications from somatic to germinal cells for patients exploring fertility journeys.

Pre-implantation genetic testing for aneuploidy: motivations, concerns, and perceptions in a UK population.

PURPOSE: Pre-implantation genetic testing for aneuploidies (PGT-A) is a technique used as part of in vitro fertilisation to improve outcomes. Despite the upward trend in women utilising PGT-A, data on women's motivations and concerns toward using the technology, and perceptions having undergone the process, remain scarce. METHODS: This cross-sectional survey, based at a fertility clinic in the UK, utilised an electronic questionnaire to assess the motivations of women who undergo PGT-A and their perceptions and attitudes toward PGT-A after using it. RESULTS: One hundred sixty-one women responded. The most significant motivating factors to undergo PGT-A were to improve the probability of having a baby per cycle (9.0 ± 2.1) and enhance the chance of implantation (8.8 ± 2.5). The least important motivations were reducing the number of embryos transferred per cycle (2.7 ± 3.3) and saving money by reducing the number of procedures required (4.6 ± 3.4). The most significant concerning factors identified included not having embryos to transfer (5.7 ± 3.4) and the potential for embryo damage (5.2 ± 3.3). The least concerning factors included religious (0.6 ± 1.7) or moral (1 ± 2.2) concerns. The majority of women were satisfied/very satisfied following treatment (n = 109; 68%). The proportion of those who were satisfied/very satisfied increased to 94.2% (n = 81) following a successful outcome, and reduced to 43.5% (n = 27) in those who had an unsuccessful outcome or had not undergone embryo transfer (p < 0.001). CONCLUSION: This study highlights that perceptions amongst women who use PGT-A are mostly positive. We also demonstrate a significant association between satisfaction and reproductive outcomes, with those who achieve a live birth reporting more positive perceptions toward PGT-A.

The First Livebirth Using Warmed Oocytes by a Semi-Automated Vitrification Procedure.

BACKGROUND: The first successful livebirth using warmed oocytes (vitrified by the GAVITM system) is reported in this paper. Embryologists throughout the world have vitrified oocytes using a manual technique which is susceptible to error and variation. In this era of automated laboratory procedures, vitrification was made semi-automatic by using the GAVITM system. CASE PRESENTATION: Donor oocytes were initially vitrified using the GAVITM system. They remained in the clinic's oocyte bank until they were allocated to the patient. Donor oocytes were warmed as per Genea BIOMEDX protocol and inseminated to create embryos. Resulting embryos for the 42-year-old patient were cultured to the blastocyst stage, biopsied to perform PGT-A, using next generation sequencing and subsequently vitrified. The patient underwent a single euploid transfer in a frozen embryo transfer cycle which resulted in a healthy livebirth. CONCLUSION: The introduction of a semi-automated system should minimize the risk to the oocytes, standardize the procedure worldwide and potentially reduce the laboratory time taken by the embryologists. This case report demonstrates the safety of the technology used for vitrification, but larger randomized studies need to be performed to demonstrate the safety and efficacy of newer technologies like the GAVITM system before adopting it as a standard laboratory procedure.

Adding a low-quality blastocyst to a high-quality blastocyst for a double embryo transfer does not decrease pregnancy and live birth rate.

INTRODUCTION: The effect of embryo quality on clinical outcomes of assisted reproductive technology following a double transfer is not well defined, with some studies suggesting that a low-quality embryo transferred with a high-quality embryo decreases the live birth rate (LBR), compared with transferring a single high-quality embryo. Our study examined whether the quality of a second blastocyst transferred affects the outcome, controlling for the number of the available high-quality blastocysts (HQB). MATERIAL AND METHODS: A historical cohort study of 2346 fresh blastocyst transfers in a single fertility clinic between 2013 and 2019. The main outcomes were pregnancy, miscarriage, live birth, and multiple gestation rates. Outcomes were compared between single embryo transfers with a high-quality blastocyst (SET-H), double embryo transfers with two HQBs (DET-HH), and transfers with one high-quality and one low-quality blastocyst (DET-HL). Outcomes were also assessed between SET and DET when only low-quality blastocysts were available. RESULTS: With one HQB available, DET-HL increased LBR (adjusted odds ratio [OR] 1.65, 95% CI 1.09-2.49) compared with SET-H, but increased multiple gestation rate (aOR 23.1, 95% CI 3.0-177.6). With two HQBs available, DET-HH was associated with a higher LBR (aOR 1.62, 95% CI 1.28-2.04) and lower miscarriage rate (aOR 0.56, 95% CI 0.40-0.80), but very high twin rate (aOR 49.8, 95% CI 24.3-102.1) compared with SET-H. A SET-H with at least one or more HQB available to freeze, compared with a SET-H with no other HQB available, had a higher LBR (aOR 1.69, 95% CI 1.17-2.45). When there were no HQBs available, compared with SET-L, a DET-LL had a higher live birth (aOR 3.20, 95% CI 1.78-7.703) and twin rate (aOR 3.72 × 1010 ) and a lower miscarriage rate (aOR 0.24, 95% CI 0.10-0.58). CONCLUSIONS: When there is one HQB available, transferring an additional low-quality blastocyst would only slightly increase the LBR, but significantly increase the twin rate, therefore SET should be recommended. When two or more HQBs are available, SET-H would have a reasonably good chance of success without the very high twin rate associated with DET-HH. DET-LL when compared with SET-L, would increase the LBR, but increase the risk of multiple gestation.

Is oocyte maturity influenced by ovulation trigger type in oocyte donation cycles?

The aim of this study was to compare clinical and laboratory outcomes between GnRHa, dual and HCG triggers in altruistic oocyte donation cycles. Normal or high responders were given either gonadotropin releasing hormone agonist (GnRHa) or a dual trigger of GnRHa and a low dose of human chorionic gonadotropin (HCG). Low responders were given HCG trigger. In 333 cycles, 232 (69.7%) received GnRHa trigger, 59 (17.7%) received dual trigger and 42 (12.6%) had HCG trigger. The total number of mature oocytes retrieved and cryopreserved were significantly higher in the GnRHa and dual trigger groups, compared to the HCG group (p < 0.001). However, the ovarian hyperstimulation syndrome (OHSS) rate was significantly higher in the dual trigger group (n = 5 (8.5%)), compared to the GnRH agonist (n = 1 (0.4%)) and HCG groups (n = 0 (0%)) (p = 0.001). GnRHa trigger maximises mature oocyte yields in oocyte donors suspected of normal and high response but offers a significant reduction in OHSS risk compared to dual trigger. As such, dual trigger should not be used in oocyte donation. HCG trigger can also be used with a very low risk of OHSS at low risk of OHSS in carefully selected donors where GnRHa is unlikely to be effective.

Preconception tests at advanced maternal age.

Pregnancies at an advanced reproductive age are increasingly common. However, the safety of pregnancy remains a concern as maternal age is a recognized independent factor for various obstetric complications. Also, age is a risk factor for most systematic health problems and older women are more likely to enter into pregnancy with pre-existing conditions. At the moment there is no separate, structured guidance on preconception tests at advanced maternal age. However, the preconceptual period offers an ideal window to recognize and address underlying health issues, social issues and harmful lifestyle behaviours in order to optimize maternal health ultimately reducing infertility, perinatal morbidity and mortality. Preconception tests should be clinically relevant aiming to identify risk factors and address them to predict and prevent infertility and pregnancy complications. The importance of preconception care is magnified for women of advanced age for whom the risks are higher and the potential benefits greater.

The Association Between Elevated Progesterone Level on Day of hCG Trigger and Live Birth Rates in ART Cycles: A Single Centre Observational Study.

BACKGROUND: The advent of ovarian stimulation within an in vitro fertilization (IVF) cycle has resulted in modifying the physiology of stimulated cycles and has helped optimize pregnancy outcomes. In this regard, the importance of progesterone (P4) elevation at time of human chorionic gonadotrophin (hCG) administration within an IVF cycle has been studied over several decades. Our study aimed to evaluate the association of P4 levels at time of hCG trigger with live birth rate (LBR), clinical pregnancy rate (CPR) and miscarriage rate (MR) in fresh IVF or IVF-ICSI cycles. METHODS: This was a retrospective cohort study (n=170) involving patients attending the Centre for Reproductive and Genetic Health (CRGH) in London. The study cohort consisted of women undergoing controlled ovarian stimulation using GnRH antagonist or GnRH agonist protocols. Univariate and multiple logistic regression analyses were used to evaluate the association of clinical outcomes. Differences were considered statistically significant if p≤0.05. RESULTS: As serum progesterone increased, a decrease in LBR was observed. Following multivariate logistical analyses, LBR significantly decreased with P4 thresholds of 4.0 ng/ml (OR 0.42, 95% CI:0.17-1.0) and 4.5 ng/ml (OR 0.35, 95% CI:0.12-0.96). CONCLUSION: P4 levels are important in specific groups and the findings were statistically significant with a P4 threshold value between 4.0-4.5 ng/ml. Therefore, it seems logical to selectively measure serum P4 levels for patients who have ovarian dysfunction or an ovulatory cycles and accordingly prepare the individualized management packages for such patients.