Successful Pregnancy Research Articles

The potential role of the prolyl isomerase Pin1 during blastocyst implantation and uterine decidualization in mice.

During early pregnancy in mice, the establishment of uterine receptivity and endometrial decidualization require the extensive proliferation and differentiation of endometrial epithelial cells or stromal cells. Pin1 has been suggested to act as a molecular 'timer' of the cell cycle and is involved in the regulation of cellular proliferation and differentiation by binding many cell-cycle regulatory proteins. However, its physiological role during early pregnancy is still not fully understood. Here, we employed immunohistochemistry to determine the spatiotemporal pattern of Pin1 expression during early pregnancy. We found that Pin1 was mainly localized in subluminal stromal cells on day 4, in the decidual zone on days 5 to 8 of pregnancy and in artificial decidualization. Using a uterine stromal cell culture system, we found that progesterone, but not estrogen, induced the expression of Pin1 in a progesterone receptor-dependent manner. Inhibition of Pin1 in the uterus leads to impaired embryo implantation and decidualization in mice. Notably, a decrease in Pin1 activation affected the functional execution of several implantation- or decidualization-related factors. These findings provide new evidence for a previously unknown function of Pin1 in mediating embryo implantation and decidualization during successful pregnancy establishment and maintenance.

3D-bioprinted gelatin methacryloyl hydrogel culture system emulating the oviduct environment for enhanced preimplantation embryo development

Oviducts have specific biomechanical properties that support fertilization and preimplantation embryo development, both of which are essential for successful pregnancy. However, conventional plastic-based human embryo culture does not recapitulate the biomechanical environment of the oviduct. Therefore, oviduct mimic culture systems that accurately emulate biophysical conditions for reproductive cells are a significant unmet clinical need. In the present study, we designed a three-dimensional (3D)-bioprinted optimal soft hydrogel system that accurately mimics the oviduct environment and investigated signaling factors during embryo development. We developed an oviduct tube-mimic hydrogel culture dish using gelatin methacryloyl (GelMA) 3D-bioprinted hydrogel. Quantitative assessment of hydrogel mechanical properties depended on the stiffness of the GelMA 3D-bioprinted hydrogel. Embryo quality was evaluated based on cleavage speed and blastocyst ratio on the GelMA hydrogel. Whole-transcriptome next-generation sequencing (NGS) analysis of embryos was used to identify biomechanical signaling factors. Our findings revealed that 10 kPa GelMA hydrogel culture conditions performed better with respect to development speed, blastocyst ratio, and hatching ratio than the control condition. Whole transcriptome NGS revealed up-regulation of mRNA processing genes and protein transport genes by the 7 and 10 kPa hydrogels. Furthermore, the inner cell mass and the number of Oct4+ cells were significantly higher in blastocysts cultured on 10 kPa hydrogel dishes than in those cultured on conventional hard plastic dishes. These findings demonstrate that optimized oviduct-mimic hydrogel-based 3D GelMA culture dishes could improve in vitro embryo development. Hence, 3D GelMA culture dishes may be useful as human embryo culture systems for assisted reproductive techniques.

Behind the Curtain of Abnormal Placentation in Pre-Eclampsia: From Molecular Mechanisms to Histological Hallmarks.

Successful human pregnancy needs several highly controlled steps to guarantee an oocyte's fertilization, the embryo's pre-implantation development, and its subsequent implantation into the uterine wall. The subsequent placenta development ensures adequate fetal nutrition and oxygenation, with the trophoblast being the first cell lineage to differentiate during this process. The placenta sustains the growth of the fetus by providing it with oxygen and nutrients and removing waste products. It is not surprising that issues with the early development of the placenta can lead to common pregnancy disorders, such as recurrent miscarriage, fetal growth restriction, pre-eclampsia, and stillbirth. Understanding the normal development of the human placenta is essential for recognizing and contextualizing any pathological aberrations that may occur. The effects of these issues may not become apparent until later in pregnancy, during the mid or advanced stages. This review discusses the process of the embryo implantation phase, the molecular mechanisms involved, and the abnormalities in those mechanisms that are thought to contribute to the development of pre-eclampsia. The review also covers the histological hallmarks of pre-eclampsia as found during the examination of placental tissue from pre-eclampsia patients.

N-acetylcysteine may improve endometrial receptivity by modulating endometrial stromal cells in goats

Abstract. Endometrial receptivity is essential for successful embryo implantation and pregnancy maintenance, and the achievement of normal physiological function of endometrial stromal cells (ESCs) is an important factor in the establishment of receptivity. N-acetylcysteine (NAC) was found to be beneficial as a small-molecule antioxidant for improving animal reproductive performance, but it is unclear whether NAC can improve receptivity by modulating ESCs in goats. In this study, we successfully isolated and cultured the ESCs of Qianbei Ma goats, used different concentrations of NAC to culture the ESCs of Qianbei Ma goats, and explored the effects of NAC on the biological functions of the ESCs of Qianbei Ma goats by using CCK-8, qRT-PCR, ELISA and flow cytometry. The results showed that 200 µmol L−1 NAC may promote the proliferation of ESCs in Qianbei Ma goats by increasing the expression of PCNA, Cyclin D2 (P<0.01) and Cyclin E (P<0.05) mRNAs. Meanwhile, 200 µmol L−1 NAC increased the cell viability (P<0.01) and enhanced the superoxide dismutase (SOD) and glutathione reductase (GR) activities (P<0.01) of ESCs in Qianbei Ma goats. In addition, 200 µmol L−1 NAC increased the mitochondrial membrane potential of ESCs (P<0.01). Notably, 200 µmol L−1 NAC promoted the expression of the mRNA of the endometrial receptivity marker genes HOXA10, PTGS2, PGR (P<0.01) and LIF (P<0.05). Thus, our results suggest that NAC may benefit the establishment of endometrial receptivity in goats by regulating the proliferation, antioxidant properties, mitochondrial membrane potential and expression of endometrial receptivity marker genes in goat ESCs.

Prolonged adhesiolysis to pregnancy interval is associated with placenta accreta spectrum in women with intrauterine adhesion

Background Both the trauma of endometrium and hysteroscopic adhesiolysis can lead to a high rate of placenta accreta spectrum (PAS) in women with intrauterine adhesion (IUA). This study analysed the impact of time interval from adhesiolysis to pregnancy on PAS in IUA women. Methods Patients diagnosed with IUA who underwent adhesiolysis in Anhui Women and Children’s Medical Centre between January 2016 and December 2020 were included in this case-series study. Clinical data were obtained from electronic medical records and telephone interviews. Results Among a total of 102 IUA women with successful pregnancies, 8 (7.8%) suffered from miscarriages with PAS, and 94 (92.2%), 47 with PAS and 47 without PAS, had successful delivery. The total prevalence of PAS in pregnant women with IUA was 53.9% (55/102). The average time from adhesiolysis to pregnancy in the PAS group was significantly longer than in the non-PAS group (14.2 ± 5.7 vs. 10.3 ± 4.4 months, p = 0.000). Regression analysis showed that AFS grade (OR = 7.40, 95% CI 1.38–39.73, p = 0.020) and adhesiolysis to pregnancy interval time between 12 and 24 months (OR = 12.09, 95% CI 3.76–38.83, p = 0.000) were closely related to PAS. A Kaplan–Meier analysis showed the median interval time to PAS was 16.00 months (95% CI 15.11–16.89). Conclusions We assume that prolonged adhesiolysis to pregnancy interval may be considered a significant risk factor for PAS in IUA women.

Targeted management of coexistent severe thrombophilias-A case report of a successful pregnancy despite paroxysmal nocturnal hemoglobinuria and hereditary protein C deficiency.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematological disorder characterized by the absence of complement regulatory proteins on the surface of erythrocytes, leading to intravascular hemolysis and thrombosis. Managing PNH during pregnancy poses significant challenges due to increased risks of morbidity and mortality. This case report describes the detailed obstetric course of a 44-year-old woman with PNH and additional hereditary protein C deficiency who had previously experienced multiple thrombotic events and adverse pregnancy outcomes (two early miscarriages and one stillbirth at 25 weeks gestation [WG]), treated with eculizumab (terminal C5 inhibitor) and optimal anticoagulation management. Close monitoring of hemolysis and hemostasis parameters was conducted throughout the gestation period together with increased obstetrical surveillance. The pregnancy progressed without thrombotic complications or breakthrough hemolysis, and the patient delivered a healthy newborn at 36 WG after induction of labor due to restricted fetal growth. To the best of our knowledge, this is the first reported case of a positive pregnancy outcome despite PNH in conjunction with hereditary thrombophilia. This case report highlights the importance of a multidisciplinary approach involving hematologists and obstetricians in the management of pregnant women with PNH. Tailored therapy, close monitoring, and comprehensive care are crucial to minimize risks and optimize outcomes.

Anti-Müllerian hormone does not predict cumulative pregnancy rate in non-infertile women following four IUI cycles with donor sperm.

To evaluate the predictive value of serum AMH for clinical pregnancy in non-infertile population undergoing intrauterine insemination with donor sperm (ds-IUI). This multicenter prospective study (ClinicalTrials.gov ID: NCT06263192) recruited all non-infertile women undergoing ds-IUI from June 2020 to December 2022 in three different fertility clinics in Spain and Chile. Indications for ds-IUI included severe oligoasthenoteratozoospermia, female partner, or single status. Clinical pregnancy rates were compared between women with AMH ≥ 1.1 and < 1.1ng/mL. The main outcome measure was the cumulative clinical pregnancy rate after up to 4 ds-IUI cycles. A total of 458 ds-IUI cycles were performed among 245 patients, of whom 108 (44.08%) achieved clinical pregnancy within 4 cycles, 60.2% of these occurring in the first attempt and 84.2% after two attempts. We found no significant differences in AMH levels or other parameters (such as age, BMI, FSH, AFC) between women who became pregnant and those who did not. Cumulative pregnancy rates and logistic regression analysis revealed that AMH ≥ 1.1ng/mL was not predictive of ds-IUI success. While a high positive correlation was observed between AFC and AMH (r = 0.67, p < 0.001), ROC curve analyses indicated that neither of these ovarian reserve markers accurately forecasts cumulative ds-IUI outcomes in non-infertile women. The findings of this multicenter study suggest that AMH is not a reliable predictor of pregnancy in non-infertile women undergoing ds-IUI. Even women with low AMH levels can achieve successful pregnancy outcomes, supporting the notion that diminished ovarian reserve should not restrict access to ds-IUI treatments in eligible non-infertile women.

SYNCHRONIZATION OF ESTRUS IN EWES

A group of 15 Awasi ewes were inserted with intravaginal sponges of Veramix plus which were removed thirteen days later. Immediately after removal of the sponges, they were injected with 500 IU of FSH intramuscularly. All ewes were came to estrus within 2-3 days after injection. They were serviced, then, after completing a successful pregnancy, all ewes had twin lambs. : This trial indicates the success of estrus synchronization in ewes.

Systemic Lupus Erythematosus in pregnancy – a multidisciplinary approach to family planning and adverse outcomes prevention

Introduction and purpose Systemic Lupus Erythematosus is a chronic multisystemic autoimmune disease with periods of remissions and flares [1,5,25]. Because of its possible consequences and unpredictability, it is undoubtedly an issue for such patients to decide about pregnancy [3]. The main aim of this review is to present the possible risks of SLE in pregnancy, its general management and current recommendations regarding pregnancy planning and pre-/postnatal care. Review Methods For the review we conducted research of scientific literature from PubMed and books, applying the keywords (below). Consequently, we included in our references above 20 selected articles published between 2017-2024 and 3 chapters of different medical books. All of these were analyzed in terms of their currency and relevance. A brief description of the State of Knowledge SLE mostly affects women at the reproductive age [2, 3,5]. It often requires long-term therapy that aims to achieve and maintain an inactive stage by means of numerous aggressive drugs. Its proper management in gestation is even more challenging than usually, owing to the increased risk of adverse pregnancy outcomes (APO) and higher maternal mortality [1,2,4,5,7]. Therefore, to achieve successful pregnancy, risk stratification, therapy modification and individually adjusted plan of follow-up visits are the most crucial conditions to be met [1,6,7,13]. Summary Considering all the potential complications that may occur in general, the issue of family planning should be raised with every female patient [5,6]. The key to the best outcomes is proper implementation of current strategies and empowering the patient to be an active and aware participant in the decision-making process [1,3,4,6,11].

Harnessing Artificial Intelligence to Predict Ovarian Stimulation Outcomes in In Vitro Fertilization: Scoping Review.

In the realm of in vitro fertilization (IVF), artificial intelligence (AI) models serve as invaluable tools for clinicians, offering predictive insights into ovarian stimulation outcomes. Predicting and understanding a patient's response to ovarian stimulation can help in personalizing doses of drugs, preventing adverse outcomes (eg, hyperstimulation), and improving the likelihood of successful fertilization and pregnancy. Given the pivotal role of accurate predictions in IVF procedures, it becomes important to investigate the landscape of AI models that are being used to predict the outcomes of ovarian stimulation. The objective of this review is to comprehensively examine the literature to explore the characteristics of AI models used for predicting ovarian stimulation outcomes in the context of IVF. A total of 6 electronic databases were searched for peer-reviewed literature published before August 2023, using the concepts of IVF and AI, along with their related terms. Records were independently screened by 2 reviewers against the eligibility criteria. The extracted data were then consolidated and presented through narrative synthesis. Upon reviewing 1348 articles, 30 met the predetermined inclusion criteria. The literature primarily focused on the number of oocytes retrieved as the main predicted outcome. Microscopy images stood out as the primary ground truth reference. The reviewed studies also highlighted that the most frequently adopted stimulation protocol was the gonadotropin-releasing hormone (GnRH) antagonist. In terms of using trigger medication, human chorionic gonadotropin (hCG) was the most commonly selected option. Among the machine learning techniques, the favored choice was the support vector machine. As for the validation of AI algorithms, the hold-out cross-validation method was the most prevalent. The area under the curve was highlighted as the primary evaluation metric. The literature exhibited a wide variation in the number of features used for AI algorithm development, ranging from 2 to 28,054 features. Data were mostly sourced from patient demographics, followed by laboratory data, specifically hormonal levels. Notably, the vast majority of studies were restricted to a single infertility clinic and exclusively relied on nonpublic data sets. These insights highlight an urgent need to diversify data sources and explore varied AI techniques for improved prediction accuracy and generalizability of AI models for the prediction of ovarian stimulation outcomes. Future research should prioritize multiclinic collaborations and consider leveraging public data sets, aiming for more precise AI-driven predictions that ultimately boost patient care and IVF success rates.

P-413 Retrospective observational study: evaluating progesterone levels on the day prior to euploid embryo transfer and its impact on pregnancy rate

Abstract Study question What significance does progesterone levels hold on the day prior to the transfer of euploid embryos, and how is this correlated with pregnancy rates? Summary answer Progesterone levels prior to embryo transfer play a crucial role in endometrial receptivity What is known already In the realm of assisted reproductive technology, creating optimal conditions for embryo transfer is crucial for successful pregnancies. Progesterone, a key hormone for endometrial receptivity, plays a pivotal role in this process. This retrospective observational study aims to evaluate the importance of progesterone levels the day before euploid embryo transfer and their correlation with pregnancy rates. For this reason, we study patients with low progesterone levels prior to transfer and the effectiveness of “rescue protocols”. Study design, size, duration This was a Retrospective Observational Study, that covers 121 women who underwent embryo transfer (euploid embryos and oocyte donation) who had their progesterone measured the day before the transfer, from January 1st 2023– December 31st 2023. The primary endpoint was pregnancy rate. Participants/materials, setting, methods During the study period, endometrial preparation was carried out by administration of progesterone, both orally or vaginally. The patients were divided into three groups based on the level of progesterone the day before the embryo transfer. • &amp;gt;10ng/mL • 8-10 ng/mL • &amp;lt;8ng/mL. These participants were treated with the daily administration of 1 or 2 doses of injectable Prolutex until confirmation of pregnancy by ultrasound. Eligible patients were aged ≤50 years with adequate endometrium thickness after receiving estrogen. Main results and the role of chance Preliminary findings underscore a significant correlation between progesterone levels exceeding 10 ng/ml the day before embryo transfer and elevated pregnancy rates. Conversely, in cases with lower progesterone levels, a personalized supplementation approach involving Prolutex demonstrates positive impacts on pregnancy outcomes. This highlights the pivotal role of tailored progesterone supplementation, utilizing Prolutex, in enhancing endometrial receptivity and, consequently, elevating the likelihood of successful pregnancies. The study emphasizes the need for personalized strategies, shedding light on the nuanced interplay between progesterone levels, supplementation methods, and the potential influence on reproductive success. As we explore these results, it becomes evident that chance alone does not govern outcomes; rather, strategic interventions hold the key to optimizing the path to successful pregnancies. Limitations, reasons for caution The main limitation of the study is the lack of randomized control studies. Furthermore, in this study, we are not including as the main group those who with low progesterone do not undergo rescue intervention with Prolutex. Wider implications of the findings Preliminary findings reveal a substantial link between progesterone levels exceeding 10 ng/ml before embryo transfer and heightened pregnancy rates. Conversely, in cases of lower progesterone, personalized Prolutex supplementation positively influences outcomes, emphasizing the pivotal role of tailored progesterone strategies in optimizing endometrial receptivity for successful pregnancies. Trial registration number not applicable

P-760 The effect of assisted hatching on pregnancy outcomes in 1,833,485 single embryo transfer based on Japan Assisted Reproductive Technology Registry System

Abstract Study question Does assisted hatching (AH) affect pregnancy outcomes especially when it was performed selectively on specified group? Summary answer No clinically significant effect of AH on pregnancy outcomes was demonstrated for the entire single embryo transfer (SET) cycle after adjusting for covariates. What is known already AH is a technique used in assisted reproduction by artificially thinning or making a small hole in the zona pellucida in order to facilitate the hatching process. It is suggested that AH may improve the chance of embryo implantation and success of pregnancy. However, there is insufficient evidence to conclude that AH improves pregnancy outcomes, despite its widespread and longtime use. In 2014, the Practice Committee of ASRM recommended that AH should not be conducted routinely for all patients. On the other hands, it has been suggested that AH could be effective for patients with poor prognosis. Study design, size, duration A retrospective observational study based on the national ART registry maintained by the Japan Society of Obstetrics and Gynecology (JSOG) was performed. The study included 1,833,485 single embryo transfer (SET) for in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) from January 2010 to December 2019. This study was approved by the Registration and Research Subcommittee of the JSOG and Tokyo University Ethics Committee. Participants/materials, setting, methods To determine the effect of AH, the rate of clinical pregnancy and live birth were compared in SET with and without AH as primary outcome measures. In addition, the prevalence of miscarriage, multiple pregnancy, ectopic pregnancy, placental malposition, and placenta accreta were analyzed as secondary outcomes. We performed inverse probability of treatment weighting and outcome regression analyses. Main results and the role of chance Out of 1,833,485 SET cycles, AH was conducted in 983,242 cycles (53.6%). In all SET cycles, clinical pregnancy rate (CRP) and live birth rate (LBR) were 31.0% vs. 26.2%, and 21.6% vs. 18.7% in AH vs. without AH group, respectively. AH was more frequently performed in patients with advanced maternal age, frozen-thawed ET cycles (88% vs. 47%, AH vs. without AH), blastocyst transfer cycles (70% vs. 42%), patients with tubal factor (17% vs 14.3%), and hormonal replacement cycles (66% vs. 43%). After adjusting for these covariates, the propensity-weighted CPR (28.4% vs. 29.1%, AH vs. without AH) and LBR (20.1% vs. 20.6%) were slightly yet significantly lower in AH group. As secondary outcomes, AH may lead to increased risk of multiple pregnancy (0.21% increase), ectopic pregnancy (0.02%), and placenta accreta (0.03%), and 0.24% decreased risk of miscarriage. On the other hands, subgroup analysis suggested that AH could be effective in the following cycles: frozen-thawed cycles with either blast or cleavage with maternal age under 35 years, and fresh blastocyst transfer cycles with maternal age over 40 years. Limitations, reasons for caution The limitation of this study is that the information regarding the history of repeated implantation failure and methods of AH were not included in this registry system. Another limitation is that duplicate data from same patients who underwent multiple embryo transfers exists in this retrospective study for 10 years. Wider implications of the findings Despite of frequent use of AH in Japan, AH in SET cycles for all patients is not recommended because of increased risk of adverse events without improvement of pregnancy outcomes. On the other hands, AH may improve pregnancy outcomes for some groups associated with maternal age and duration of culture. Trial registration number not applicable’

P-137 A deep learning model using time-lapse imaging data to predict successful clinical pregnancy and embryo euploidy

Abstract Study question Are the deep learning models helpful in selecting embryos with a high probability of clinical pregnancy and euploidy from time-lapse imaging during embryo growth? Summary answer Our deep learning models using time-lapse imaging data predicted the probabilities of successful clinical pregnancy and euploidy of embryos with high accuracy. What is known already Recent studies have attempted to select the most viable embryo using deep learning of time-lapse imaging during incubation. However, most studies included embryos that were not transferred due to low evaluation by the embryologist as embryos with unsuccessful pregnancies, or they mixed single and multiple embryo transfer cases in the analyses. Some studies’ algorithms rely on humans’ subjective interpretation of morphological and morphokinetic features, leading to embryologist-to-embryologist and within-embryologist variabilities. Some reports, including the study predicting embryo aneuploidy, used a snapshot image for prediction. These approaches have restricted the potential of deep learning in embryo selections. Study design, size, duration Retrospective analyses of time-lapse videos of 2,192 embryos with clinical pregnancy outcomes, defined as confirmed gestational sacs in utero, and 1,467 embryos with karyotype outcomes examined by preimplantation genetic testing for aneuploidy (PGT-A). The data were obtained from two different in-vitro fertilization clinics between November 2017 and December 2021. All transfers were performed as a single embryo transfer. Participants/materials, setting, methods The deep learning model was trained using time-lapse videos with known clinical pregnancy outcomes for predicting the probability of clinical pregnancy with given time-lapse video sequences and patient ages (CP model). Another deep learning model was trained using time-lapse videos with known karyotype outcomes by PGT-A for predicting the probability of euploidy (AP model). The models’ predictive powers were measured using the average area under the curve (AUC) of the receiver operating characteristic curve. Main results and the role of chance The CP model predicted clinical pregnancy with an AUC of 0.693. The AP model predicted embryo aneuploidy with an AUC of 0.702. Limitations, reasons for caution The CP model is based on the embryos that were transferred because the embryologist judged them as having a high probability of pregnancy. Clinical pregnancy may be associated with maternal factors besides embryo factors. Wider implications of the findings Our two deep learning models, the CP and AP models, will be helpful for selecting the embryos to be transferred. The CP model may increase pregnancy rates in patients undergoing assisted reproductive technology. The AP model may reduce the miscarriage caused by embryo aneuploidy. Trial registration number not applicable

O-063 How does the exclusion of blastomeres affect the outcome of euploid blastocysts?

Abstract Study question Do euploid blastocysts with excluded blastomere(s) have the same probability of live birth when compared to euploid blastocysts without excluded blastomere(s)? Summary answer Euploid blastocysts with excluded blastomere(s) have significantly worse pregnancy outcomes, with the live birth rate being 10% lower than those without any exclusion pattern. What is known already Blastomeres that have arisen at any time throughout cleavage-stage are sometimes excluded from the formation of the blastocyst and once isolated, those cells do not take further part in preimplantation development. Embryos harboring cell exclusion were found to have altered morphokinetic profiles; S2(second synchrony) and ECC3(embryonic cell cycle 3) were described as useful in identifying increased odds of FHB when a cell exclusion event was present (Kakulavarapua et al., 2023). Besides, pregnancy and live birth rates were reported to progressively decrease in a non-PGT-A (preimplantation genetic testing for aneuploidy) tested cohort with excluded or extruded blastomere(s) (Coticchio et al., 2021). Study design, size, duration This retrospective study included 667 euploid blastocysts with excluded blastomere(s) and 3830 euploid blastocysts without excluded blastomere(s). All were transferred between 2017 and 2023. No discrimination was made between cells failing to compact because of their exclusion from the compaction process (excluded from a partially compacted morula), and cells extruded after an initial inclusion in the compacted embryonic mass (extruded from a partially compacted morula). Participants/materials, setting, methods A total of 4497 IVF patients treated in a single private clinic were included in this retrospective study. Their blastocysts were subjected to PGT-A mainly for advanced maternal age. The analysis was done by next generation sequencing (NGS) (Ion Torrent S5, Thermo Fisher). Vitrified-warmed euploid blastocysts were then transferred in a next cycle. Pregnancy and miscarriage rates were compared between blastocysts with and without excluded blastomere(s) by chi-square test. Main results and the role of chance The outcomes of euploid blastocysts with excluded blastomeres (n = 667) were compared to euploid blastocysts without excluded blastomeres (n = 3830). The biochemical pregnancy rate was 71.6% and 77%, respectively (p = 0.0026). The clinical pregnancy rate was 61.3% and 70.6%, respectively (p = 0.0001). The ongoing pregnancy rate was 53.7% and 63.3%, respectively (p = 0.0001). The biochemical miscarriage rate nearly doubled with the presence of excluded blastomere(s) (14% vs. 8.3%, respectively; p = 0.0001). The clinical miscarriage rate was 12.7% and 10.4%, respectively (ns). Ultimately, the live birth rate was 46.3% for the blastocysts with excluded blastomere(s), compared to 57.6% for the blastocysts without excluded blastomere(s) (p = 0.0001). Limitations, reasons for caution No discrimination was made between cells excluded from a partially compacted morula and cells extruded after an initial inclusion in the compacted embryonic mass. Wider implications of the findings Although blastocysts with excluded blastomere(s) are not the first choice for transfer, our results show that, although at lower rate, successful pregnancies and live births occur. A complete time-lapse culture evaluation not limited to cell division time points may propose indicators to identify higher implantation potential blastocysts with excluded blastomere(s). Trial registration number N/A

P-157 Comparative analysis of iDAScore and KIDScore in predicting live birth following single frozen day 5 blastocyst transfer

Abstract Study question How do iDAScore® and KIDScoreTM perform in predicting live birth outcomes after single frozen Day 5 blastocyst transfers? Summary answer In a euploid major cohort, both KIDScoreTM and iDAScore® demonstrated comparable predictive ability for live birth. However, iDAScore® offers the advantage of being fully automated. What is known already In the field of in vitro fertilization (IVF), the escalating use of artificial intelligence (AI) for predicting clinical outcomes is a burgeoning trend. One key contributor to this trend is time-lapse incubation, which captures images of developing images, generating a wealth of data. This data has facilitated the creation of various predictive models for implantation. KIDScoreTM is one such model that uses morphokinetic data to predict the probability of implantation after a Day 5 embryo transfer. Similarly, iDAScore® is an AI-driven automated scoring system specifically designed to automatically identify embryos with the greatest likelihood of implantation. Study design, size, duration This retrospective study included 779 patients (maternal age range: 19-44, mean age: 33.38) who underwent single frozen day 5 blastocyst transfer cycle from January 2021 to January 2023. Of these, 621 patients transferred euploid blastocysts, 48 transferred mosaic blastocysts, and 110 transferred non-PGT-A tested blastocysts. This study comprised of 12.1% (94/779) fair-to-good and fair grade (below AB and BA), 51.5% (401/779) good grade (AB and BA), and 36.4% (284/779) excellent grade (AA) blastocysts. Participants/materials, setting, methods After PIEZO-ICSI, embryos were cultured in EmbryoScopeTM Plus (Vitrolife, Denmark) until they reached the blastocyst stage. Blastocysts graded at least as fair according to Gardner (1999), were either biopsied for PGT-A and vitrified (Cryotec, Japan), or vitrified without biopsy. Clinical pregnancy and the number of gestational sacs were determined using ultrasound and successful pregnancies were tracked until delivery. KIDScoreTM (KIDScoreTM Day 5 v3.2) and iDAScore® (iDAScore® v2.0) were retrospectively generated for each transferred blastocyst. Main results and the role of chance Box plot showed that both KIDScoreTM and iDAScore® have positive correlation with morphology (Excellent vs. Good vs. Fair-to-Good and Fair; KIDScoreTM median: 8.8 vs. 6.8 vs. 5.7; iDAScore® median: 8.57 vs. 7.68 vs. 6.615), ICM (A vs. B; KIDScoreTM median: 7.5 vs. 6.5; iDAScore® median: 8.14 vs. 7.26) and TE (A vs. B vs. C; KIDScoreTM median: 8.7 vs. 6.5 vs. 4.65; iDAScore® median: 8.41 vs. 7.515 vs. 5.2). In this cohort, the overall implantation rate was 67.91% (529/779), and the live birth rate was 59.31% (462/779). Further statistical analysis revealed interesting correlations. A linear regression analysis indicated a statistically significant positive correlation between KIDScoreTM and iDAScore® (F(1,777)=297.6, p &amp;lt; 0.001, adjusted R2=0.276). Wilcoxon rank sum tests showed that KIDScoreTM has significant higher mean scores in blastocysts resulting in live birth compared to those that did not (7.44 vs. 7.22, w = 66577, p &amp;lt; 0.05). iDAScore® also had higher mean scores in blastocysts resulting in live birth but without statistically significant difference (7.56 vs. 7.48, w = 71328, p &amp;gt; 0.05). ROC curve analysis showed that AUC for KIDScoreTM was 54.4 and AUC for iDAScore® was 51.9, indicating no significant difference in their predictive ability for live birth (p = 0.2455). Limitations, reasons for caution The study’s cohort predominantly consisted of blastocysts with good morphology and were euploid, potentially skewing the results. Therefore, the findings may not be representative of all IVF patients and should be interpreted with caution. Additionally, further study should investigate the capability of iDAScore® 2.0 to predict euploidy. Wider implications of the findings While KIDScoreTM had a higher AUC than iDAScore®, there was no statistically significant difference. The major advantage of iDAScore® lies in its automation, eliminating the need for manual embryo evaluation. This can greatly enhance consistency in embryo grading and selection. Trial registration number NOT APPLICABLE

P-228 Competence of injected MI versus MII sibling oocytes in terms of normal fertilization, blastocyst development and euploidy

Abstract Study question Is the injection of immature MI oocytes as effective as injection of their siblings mature MII oocytes regarding normal fertilization, blastocyst development and euploidy? Summary answer MI oocytes show a lower rate of fertilization, a similar blastulation rate, and a slightly lower rate of euploidy compared to their MII sibling oocytes. What is known already Although several studies have been performed on immature MI oocytes evaluating their developmental competence after intracytoplasmic sperm injection (ICSI), all have been performed on oocytes that extruded the first polar body by the time of injection. ICSI is typically performed on MII oocytes which have completed the process of maturation. Some laboratories also inject MI oocytes, nevertheless, they are generally not used due to the lack of required molecular and cellular changes to support normal development. However, there is limited research on the reproductive potential of oocytes in MI. Consequently, our current practices are founded on assumptions. Study design, size, duration This is a retrospective, observational study of 168 oocytes injected in MI and 839 sibling oocytes injected in MII from 82 ICSI cycles with Preimplantation Genetic Testing for Aneuploidies (PGT-A) performed in a single IVF clinic between April 2018 and December 2023. All PGT-A cycles included in this study contained at least one MI oocyte injected. Participants/materials, setting, methods After oocyte retrieval and denudation, the oocytes were classified as MII, MI or GV. MI oocytes with extruded polar body by the moment of ICSI were reclassified as MII. All MII and MI oocytes were inseminated and the embryos that reached blastocyst stage were biopsied on day 5, 6 or 7. Normal fertilization rate, blastocyst formation rate and euploidy rate were compared between MI-derived embryos and their MII-derived siblings. Main results and the role of chance A total of 1,094 oocytes were retrieved from 83 ICSI cycles with PGT-A, comprising 839 (76.7%) MII, 168 (15.4%) MI y 87 (7.9%) VG. The normal fertilization rate was significantly higher in oocytes injected at MII compared to MI (76.9% vs 53.0%, P &amp;lt; 0.001). The rates of abnormal fertilization in MII and MI oocytes were as follows: 1 PN 0.8% vs 0.6%, P = 0.342; 3PN 2.6% vs 1.2%, P = 0.075; 0 PN 19.7% vs 45.2%, P &amp;lt; 0.001. Interestingly, the blastulation rate of zygotes with normal fertilization was very similar between both groups (46.4% vs 43.8%, P = 0.708), as well as the proportion of biopsied blastocysts on day 5 (74.2% vs 71.8%, P = 0.858), on day 6 (23.1% vs 25.6%, P = 0.946), and on day 7 (2.7% vs 2.6%, P = 0.594). The euploidy rate of the 298 biopsied MII-derived blastocyst was 36.2%, compared with 23.1% of the 39 MI-derived blastocysts biopsied (P = 0.077). Despite the limited sample size, it is noteworthy that three out of the four euploid blastocysts derived from MI oocytes, which were transferred in single embryo transfers, successfully led to pregnancy resulting in one healthy live birth, one ongoing pregnancy and one miscarriage at 9 weeks of pregnancy. Limitations, reasons for caution While this study provides valuable insights into the developmental competence of MI oocytes, it is not exempt from certain limitations, such as its retrospective nature, limited sample size and ethical considerations regarding the injection of putative immature oocytes. Wider implications of the findings MI oocytes showed lower fertilization rates compared to their MII siblings. However, once fertilized, MI-derived embryos had similar blastulation rates and a trend towards lower euploidy rates. Our study suggests that MI oocytes may result in successful pregnancies and live birth, but further research is needed to validate these findings. Trial registration number Not applicable

O-234 Indication for fertility preservation in patients with endometriosis

Abstract Endometriosis is a complex gynecological condition that not only causes debilitating symptoms but also significantly impacts fertility. As the disease affects approximately 10% of women of reproductive age, addressing fertility preservation strategies becomes paramount. The conventional treatments for endometriosis, such as medical therapy and surgery, often fail to fully address its adverse effects on ovarian reserve and reproductive potential. Consequently, there is a growing interest in exploring fertility preservation options, particularly oocyte cryopreservation (OOC), for endometriosis patients. Despite the prevalence and impact of endometriosis on fertility, comprehensive data and guidelines specifically tailored to fertility preservation in this population remain scarce. The available evidence suggests that endometriosis, particularly when it involves ovarian endometriomas, is associated with a significant reduction in ovarian reserve, as indicated by lower levels of anti-Müllerian hormone (AMH). Surgical interventions, often necessary for managing endometriosis-related complications, can further compromise ovarian function and diminish fertility prospects. However, recent studies have shed light on the potential benefits of OOC in preserving fertility for endometriosis patients. OOC offers a minimally invasive approach with no impact on ovarian reserve compared to other fertility preservation techniques. Despite the lack of randomized controlled trials, our retrospective data have demonstrated promising outcomes, with a notable number needed to treat (NNT) of 16 for one successful pregnancy. This underscores the significance of discussing and considering OOC as part of the treatment plan for endometriosis patients, especially those at risk of ovarian compromise due to the disease or its management. The decision to pursue fertility preservation through OOC should be made on a case-by-case basis, taking into account various factors such as disease severity, patient age, ovarian reserve, and treatment history. French guidelines recommend considering OOC for endometriosis patients with bilateral ovarian endometriomas larger than 3 cm or those with endometriomas on a single ovary. Initiating fertility preservation discussions early, preferably before surgical intervention, allows patients to make informed decisions regarding their reproductive future. It is crucial to acknowledge the challenges and uncertainties associated with fertility preservation in endometriosis patients. Socio-economic factors, patient preferences, and the lack of clear criteria for selecting candidates for OOC pose significant hurdles. Furthermore, the effectiveness and cost-effectiveness of OOC in this population warrant further investigation. In addition to OOC, alternative fertility preservation options, such as ovarian tissue preservation, could be considered, particularly in cases where ovarian stimulation is not feasible or declined by the patient. However, data on the efficacy and safety of ovarian tissue preservation specifically in endometriosis patients are limited, highlighting the need for further research in this area. In conclusion, fertility preservation, particularly through OOC, holds promise for mitigating the adverse effects of endometriosis on ovarian function and fertility. While uncertainties persist, integrating fertility preservation discussions into the comprehensive management of endometriosis is essential. This ensures that patients are empowered to make informed decisions about their reproductive health and maximizes their chances of achieving desired fertility outcomes despite the challenges posed by endometriosis.

P-062 The impact of isolated teratozoospermia on cumulative live birth rates in IVF and ICSI treatment: a retrospective analysis of 5254 completed cycles

Abstract Study question To assess fecundity using cumulative live birth rate (CLBR) per egg collection to determine if IVF and ICSI outcomes are significantly influenced by sperm morphology. Summary answer The presence of isolated teratozoospermia does not have a significant impact on the CLBR of IVF treatment. What is known already There is ongoing debate regarding the clinical significance. Some studies indicate a pivotal role of sperm morphology in successful pregnancies, others cast doubt on its reliability as a predictive factor. Despite the application of stringent grading criteria, concerns remain about the subjective nature of assessing sperm morphology. Discrepancies in success rates between normozoospermic and isolated teratozoospermic groups shown by previous research findings underscore the uncertainty surrounding this matter. Inconsistent findings in previous research may be explained by limited sample sizes and a focus on immediate successes, neglecting subsequent frozen cycles. This study seeks to address the overlooked aspects of teratozoospermia. Study design, size, duration A retrospective study was conducted at Waterstone Clinic, involving 5254 IVF/ICSI autologous cycles completed between 2009-2022 cycles (completed meaning all embryos were either transferred or disposed of). Cycles were categorised according to sperm morphology and divided into two groups: the isolated teratospermic (ITS) group (1218 cycles) defined as having less than 4% normal morphologic forms with all other semen parameters being normal, and the normal sperm (NS) group (4036 cycles). Participants/materials, setting, methods The primary outcome measures, included fertilisation rate, number of cryopreserved embryos per egg collection, and CLBR. Employing multivariate statistics, the analysis explored the impact of interferons on CLBR in relation to variables such as sperm morphology, female age, egg number, and aetiology. Main results and the role of chance The female base characteristics were similar between the two groups in terms of age (37.1 vs 37.1 y/o), oocyte number (9.4 vs. 9.7) and FSH level (7.6 vs. 7.6 IU/L). Statistically significant differences were observed in fertilisation rates (61.7% vs. 65.8%, p &amp;lt; 0.001) and fertilisation failure (5.9% vs. 3.3%, p &amp;lt; 0.001) from IVF treatments when comparing the ITS and the NS groups. However, there was not any significant difference in the number of cryopreserved embryos between the two groups. Additionally, the CLBR did not show any significant difference between the two groups for IVF (35.8% vs. 37.8%, p &amp;gt; 0.05) or ICSI treatments (38.1% vs. 33.2%, p &amp;gt; 0.05). ICSI did not confer any benefit in improving the CLBR outcome when compared to conventional IVF, when adjusted for female age, number of oocytes collected, and aetiology. Limitations, reasons for caution While this study is retrospective it encompasses a substantial cohort. A potential for bias due to the selection criteria for IVF and ICSI exists. The intrinsic subjectivity in sperm morphology assessment introduces additional potential bias. Wider implications of the findings Despite the lack of support from CLBR to advocate for choosing ICSI in patients with ITS, this study suggests that couples with ITS experience lower fertilisation and higher fertilisation failure rates with IVF. This observation can serve as a valuable indicator for investigating the occurrence of fertilisation failure. Trial registration number not applicable

P-329 Evaluating Implansera, autologous platelet-derived growth factors, to improve clinical pregnancy and live birth rates in frozen embryo transfer for women with recurrent implantation failure

Abstract Study question Can Implansera, Autologous Platelet-Derived Growth Factors, serve as a promising adjuvant therapy in assisted reproductive techniques to enhance endometrial thickness and implantation rates? Summary answer Use of Implansera significantly increased clinical pregnancy and Live Birth Rate In Patients With repeated implantation failure during FET cycles. What is known already Insufficient endometrial thickness and receptivity contribute to Recurrent Implantation Failure (RIF), prompting consideration of surrogacy. Despite global rise in Frozen Embryo Transfer (FET), quest for an optimal implantation protocol persists. Recent research highlights platelet-rich plasma (PRP) as promising solution for thin endometrium and RIF cases, attributing positive outcomes to PRP’s high growth factor concentration. Recognizing the need for precise platelet and growth factor concentrations, Implansera—a specialized platelet-derived growth factor concentrate—was developed. This innovation addresses the challenge of unresponsive endometrium, offering tailored solution to maximize therapeutic efficacy and improve pregnancy outcomes for patients facing RIF issues. Study design, size, duration Conducted from May 2021 to December 2023, this prospective interventional self-controlled study focused on 21 women (aged 30-48) experiencing recurrent IVF failure due to stubborn thin endometrium. Selected after negative hysteroscopic and bacteriologic screenings, and unsuccessful pregnancies despite multiple immune therapy regimens, such as intralipid and granulocyte colony-stimulating factor infusions, steroids, and endometrial scratching. The subjects underwent Implansera treatment, aiming to address refractory thin endometrium and potentially enhance their chances of successful conception. Participants/materials, setting, methods After obtaining informed consent women with at least two previous unexplained RIF, who were candidates for frozen-thawed embryo transfer were treated with intrauterine infusion of 0.8 ml of Implansera was infused into uterine cavity in addition to standard HRT protocols 2 days before ET. Clinical pregnancy was determined by positive serum β-HCG, 2weeks after ET and presence of fetal heart beat in trans-vaginal ultrasound 5weeks after ET. Main results and the role of chance Among 21 women, 10 achieved pregnancy (47.6%), while 11 did not conceive (52.4%). Clinical outcomes varied: 1 woman (4.8%) experienced chemical pregnancy, 3 (14.3%) miscarried before 6-12 weeks, 3 (14.3%) delivered healthy full-term babies, and 3 (14.3%) are in the 24th week of uneventful gestation accounts for 28.6% cumulative successful pregnancy outcomes. Implansera treatment yielded no reported adverse effects.Implansera, prepared through a patented proprietary process, standardized to contain 6-9 times higher growth factors than peripheral blood, particularly implantation-friendly and anti-inflammatory cytokines, addresses the crucial angiogenic and anti-inflammatory requirements for successful implantation. Tailored for the cyclical demands of endometrial proliferation, secretion, and implantation phases, it efficiently restores impaired uterine environments.Beyond efficacy, Implansera’s safety, reproducibility, and effectiveness in emulating natural tissue repair and regeneration processes are noteworthy. Studies underscore the significance of creating an environment conducive to successful implantation, and Implansera’s composition aligns with these requirements. Its capacity to mimic natural processes positions it as a promising solution, offering a comprehensive approach to enhancing endometrial receptivity, thus optimizing conditions for successful pregnancies. Limitations, reasons for caution This self-controlled prospective study, albeit with small sample size and lacking randomized control group, aligns with published data in demonstrating Implansera’s benefits. Proposing larger studies, particularly with unexplained RIF, to establish Implansera as routine IVF adjuvant. Further investigations aim to identify active molecules influencing implantation and suggest targeted recommendations. Wider implications of the findings Implansera improved implantation, pregnancy, and live birth rates (LBR) in unexplained RIF patients which indicates clearly endometrial thickness and receptivity improvement and motivated us to plan randomized controlled studies to confirm the results and provide opportunity for women with unexplained RIF to conceive and deliver in lesser number of cycles. Trial registration number Not applicable

O-028 DNA methylation testing with cervical secretion can serve as a non-invasive biomarker for predicting successful implantation in frozen-thawed embryo transfer

Abstract Study question Is cervical secretion gene methylation profile associated with embryo implantation outcome, and can be used as a non-invasive biomarker for pregnancy prediction in FET cycles? Summary answer Cervical secretion gene methylation profiles show significant associations with implantation outcomes, and can serve as a non-invasive predictor of successful pregnancy in FET cycles. What is known already Cause of implantation failure remains a black box in reproductive medicine, and the exact mechanism of how endometrial receptivity is still behind the curtain. Epigenetic modifications including DNA methylation regulate gene expression and may alter endometrium receptivity. Endometrial DNA methylation changes vigorously only during the reconstruction of a new endometrium throughout each menstrual cycle, suggesting a unique methylation landscape in each regenerated endometrium. Cervical secretions contain implantation-related cytokines and genetic material from endometrium, and the DNA methylation profiles of cervical secretions is highly correlated with endometrium. Therefore, cervical secretions can be used as non-invasive surrogates for investigating endometrial condition. Study design, size, duration This multi-centered, case-control study enrolled 72 infertile females who entered the FET cycle with at least one high-quality blastocyst available between Aug 2017 and Dec 2022. Embryos assessed by Gardner scoring system with grade 3BB or above were defined as high-quality. Cervical secretions were collected on the day right before embryo transfer, and then DNA methylation profile were assessed. Participants/materials, setting, methods These females aged between 20-45 years-old with regular menstruation cycle (24-35 days) and normal BMI (17.5–32.0 kg/m2). Uterine cavity lesions and hydrosalpinx without treatment, adenomyosis, large uterine myoma that distorted endometrium, and thin endometrium (&amp;lt;7mm) were excluded. The association between the cervical secretion gene methylation profile and pregnancy outcome was evaluated via quantitative methylation-specific PCR (qMSP), methylation array, and genome-wide analysis. Different machine learning algorithms were utilized for differential methylation analysis and implantation prediction. Main results and the role of chance Cervical secretion DNA methylome differed between receptive (pregnant) and non-receptive (non-pregnant) FET cycle with genome-wide methylation array. The accuracy of pregnancy outcome prediction using top 2000 differential methylation probes (DMPs) in promoter region can be as high as 86% in all tested sample and 96.4% in pregnant samples. Bioinformatic analysis of six selected candidate genes related to implantation from literature review showed significant differences in DNA methylation between receptive and non-receptive endometrium. The methylation level of the six candidate genes with eight regions were measured by the qMSP platform and showed varying degrees of differential methylation status between the pregnancy and non-pregnancy groups. The AUCs for a single gene/region ranged from 0.53–0.67 for implantation prediction. Ten different machine learning models were applied and the results showed that the combination of candidate genes’ DNA methylation profiles could differentiate pregnant from non-pregnant samples with an accuracy as high as 86.67% and an AUC of 0.81 by logistic regression model. The best model from different machine learning algorithms using selected DMPs of genes related to window of implantation (WOI) can predict ongoing pregnancy with accuracy rates as high as 86.78% and AUC values up to 0.91. Limitations, reasons for caution The results obtained from a relatively small cohort size, and the timing of sample collection is on the day right before embryo transfer. Further investigation of methylation profiles in late follicular phase along with large sample size with euploid embryo transfer are mandatory for validation and clinical applications. Wider implications of the findings We firstly demonstrated the feasibility of cervical secretion methylation profile as a non-invasive testing for pregnancy prediction. The promising result may contribute to predicting endometrial receptivity for cycles with a favorable endometrium and maximize the successful pregnancy rate of embryo transfer. Trial registration number not applicable