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.

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.

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.

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.

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.

Perceptions, outcomes, and regret following social egg freezing in the UK; a cross-sectional survey.

INTRODUCTION: Social egg freezing enhances reproductive autonomy by empowering women with the capacity to delay their childbearing years, while preserving the opportunity to maintain biological relation with subsequent offspring. However, age-related obstetric complications, economic implications and the risk of unsuccessful future treatment make it a controversial option. Despite the upward trend in women electively cryopreserving their eggs, there is limited data about the women's perceptions, having undergone the process. The aim of this study was to investigate the motivations of women who have undergone social egg freezing, identify their perceptions following treatment, and assess potential feelings of regret. MATERIAL AND METHODS: This cross-sectional survey, based at a fertility clinic in the UK, used an electronic questionnaire to assess the motivations and perceptions of women who underwent social egg freezing between 1 January 2008 and 31 December 2018. RESULTS: One hundred questionnaires were distributed, and 85 women responded (85% response rate). The most frequent reason for freezing oocytes was not having a partner with 56 (70%) women saying it "definitely" influenced their decision. The majority of women (83%; n = 68) knew there was a chance of treatment failure in the future and that a live birth could not be guaranteed. More than half (n = 39; 51%) disagreed or strongly disagreed that the 10-year UK storage limit is fair. One-third of respondents (n = 17; 33%) felt the storage time should be indefinite and 29% (n = 15) believed it should be up to the age of 50. Twenty percent (n = 15) of the women who underwent social egg freezing have successfully had a baby or are currently pregnant, half (n = 8; 53%) of whom conceived spontaneously and a quarter (n = 4; 26%) used their stored oocytes. In all, 91% (n = 73) had no regrets over their decision to undergo social egg freezing. CONCLUSIONS: We demonstrate herein important and novel insights into the motivations and perceptions of women from a UK population who have undergone social egg freezing. Despite potential physical, psychological, and financial burdens, only a small minority of women experience regret after social egg freezing. We also highlight clear discontent with the Human Fertilisation & Embryology Authority storage limit among social egg freezers in the UK.

Correction to: Contraction behaviour reduces embryo competence in high-quality euploid blastocysts.

The original version of this article unfortunately contained a mistake in the author group section.

Contraction behaviour reduces embryo competence in high-quality euploid blastocysts.

PURPOSE: The aim of the study is to investigate how blastocyst contraction behaviour affects the reproductive competence in high-quality euploid embryos. METHODS: Eight hundred ninety-six high-quality blastocysts derived from 190 patients (mean age 38.05 (SD = 2.9) years) who underwent preimplantation genetic testing for aneuploidies (PGT-A) from January 2016 to October 2017 were included in this study. PGT-A results were reported as euploid or aneuploid. Aneuploid embryos were sub-classified into three categories: monosomy, trisomy and complex aneuploid. Retrospective studies of time-lapse monitoring (TLM) of those embryos were analysed and reproductive outcome of transferred embryos was collected. RESULTS: A total of 234/896 were euploid (26.1%) whilst 662/896 (73.9%) blastocysts were proven to be aneuploid from which 116 (17.6%) presented monosomies, 136 (20.5%) trisomies and 410 (61.9%) were complex aneuploid. The most frequent chromosomal complements were trisomies affecting chromosome 21 and monosomies involving chromosomes 16 and 22. Data analysis showed a statistical difference in the number of contractions being reported greater in aneuploid when compared to euploid embryos (0.6 vs 1.57; p < 0.001). Analysis of the aneuploid embryos showed that monosomies present less number of contractions when compared to embryos affected with trisomies or complex aneuploidies (1.23 vs 1.53 and 1.40; p < 0.05). No difference was observed when comparing the latter two groups. Euploid embryos presenting at least one contraction resulted in lower implantation and clinical pregnancy rates when compared to blastocysts that do not display this event (47.6 vs 78.5% and 40.0 vs 59.0% respectively). CONCLUSIONS: Most aneuploid blastocysts diagnosed by PGT-A have complex aneuploidies, showing that aneuploid embryos can develop after genomic activation and reaching high morphological scores. It becomes clear that embryo contraction, despite being a physiological feature during blastulation, is conditioned by the ploidy status of the embryo. Furthermore, the presence of contractions may compromise implantation rates.

A Comparative Analysis of Outcomes Between Two Different Intramuscular Progesterone Preparations in Women Undergoing Frozen Embryo Transfer Cycles.

Background: The purpose of the current study was to assess if luteal support with intramuscular (IM) 17 alpha-hydroxyprogesterone caproate (17-OHPC) (Lentogest, IBSA, Italy) improves the pregnancy outcome in comparison to natural intramuscular progesterone (Prontogest, AMSA, Italy) when administered to recipients in a frozen embryo transfer cycle. Methods: A retrospective comparative study was performed to evaluate outcomes between two different intramuscular regimens used for luteal support in frozen embryo transfer cycles in patients underwent autologous in vitro fertilization (IVF) cycles (896 IVF cycles) and intracytoplasmic sperm injection (ICSI) who had a blastocyst transfer from February 2014 to March 2017 at the Centre for Reproductive and Genetic Health (CRGH) in London. Results: The live birth rates were significantly lower for the IM natural progesterone group when compared to 17-OHPC group (41.8% vs. 50.9%, adjusted OR of 0.63 (0.31-0.91)). The miscarriage rates were significantly lower in the 17-OHPC group compared to the IM natural progesterone group (14.5% vs. 19.2%, OR of 1.5, 95% CI of 1.13-2.11). The gestational age at birth and birth weight were similar in both groups (p=0.297 and p=0.966, respectively). Conclusion: It is known that both intramuscular and vaginal progesterone preparations are the standard of care for luteal phase support in women having frozen embryo transfer cycles. However, there is no clear scientific consensus regarding the optimal luteal support. In this study, it was revealed that live birth rates are significantly higher in women who received artificial progesterone compared to women who received natural progesterone in frozen embryo transfer cycles.

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.

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.

The First ongoing Pregnancy Following Comprehensive Aneuploidy Assessment Using a Combined Blastocenetesis, Cell Free DNA and Trophectoderm Biopsy Strategy.

BACKGROUND: The exact origin of cell-free DNA found in spent culture media or blastocoel fluid is currently unknown but with the potential to become an improved source of DNA for chromosomal analysis than trophectoderm biopsy samples, it provides a superior representation of the fetal genetic status. However, the genetic material contained within the blastocoel cavity may be more reliable to assessment of embryo euploidy in a clinical context than trophectoderm of cell-free DNA. CASE PRESENTATION: This is the first UK case report where all three sources of DNA were analyzed in a clinical setting on 29 th January 2018 at the Centre for Reproductive and Genetic Health, London, leading to an ongoing clinical pregnancy. CONCLUSION: The experience from this case report suggests that removal of blastocoel fluid, sampling of spent culture media and trophectoderm biopsy can be carried out in parallel. Gathering genetic information from two to three independent samples of embryo DNA may provide enhanced diagnostic accuracy and may clarify cytogenetic status of mosaic embryos.