Effect of blastomere cell number on ART outcome of fresh single day 3 embryo transfer.

PURPOSE: Explore the effect of blastomere cell number on ART outcome of fresh embryo transfer on day 3. METHODS: Retrospective analysis of 540 fresh single day 3 embryo transfer cycles at the Reproductive Center of the Third Affiliated Hospital of Guangzhou Medical University from January 1, 2018 to October 31, 2022. Patients were divided into 5-6 cell group (n = 55), 7-9 cell group (n = 457), and ≥ 10 cell group(n = 28) based on the number of blastomeres. Single factor analysis of variance and Pearson's chi square test were used to compare the basic data, cycle information, pregnancy outcome and neonatal outcome. Univariate logistic regression was used to correct for confounding factors and analyze the influencing factors of pregnancy outcome. RESULTS: The positive HCG rate were 20%, 43%, 25% for the 5-6-cell, 7-9 cell and ≥ 10 cell groups respectively, with statistically significant differences (P < 0.001). The clinical pregnancy rate was 18%, 42%,21%, respectively (P < 0.001). The live birth rates were 13%, 34%,21% with P-value less than 0.05 which is statistically significant. In order to exclude the influence of confounding factors, multivariable logistic regression analysis was performed, and the outcomes were consistent with previous findings. There were no significant differences found in neonatal outcome between groups (P > 0.05). CONCLUSION: The results suggested that intermediate cleaving embryos (7-9 cell) still presents the highest clinical potential. Fast and slow cleaving embryos are not conducive to the ART outcome.

Live birth rate after oocyte donation in females diagnosed with turner syndrome: a systematic review and meta-analysis.

BACKGROUND: An enduring challenge for women diagnosed with Turner syndrome (TS) is infertility. Oocyte donation (OD) offers a chance of pregnancy for these patients. However, current data on pregnancy outcomes are inadequate. Hence, this systematic review aims to explore the clinical outcomes of OD in patients with TS. METHODS: A systematic search was conducted in PubMed, Web of Sciences, Scopus, and Embase for relevant papers from 1 January 1990 to 30 November 2023. Our primary research objective is to determine the live birth rate among women with TS who have undergone in vitro fertilization (IVF) using OD for fertility purposes. Specifically, we aim to calculate the pooled live birth rates per patient and per embryo transfer (ET) cycle. For secondary outcomes, we have analyzed the rates of clinical pregnancy achievement per ET cycle and the incidence of gestational hypertensive complications per clinical pregnancy. Prevalence meta-analyses were performed using STATA 18.0 by utilizing a random-effects model and calculating the pooled rates of each outcome using a 95% confidence interval (CI). RESULTS: A total of 14 studies encompassing 417 patients were systematically reviewed. Except for one prospective clinical trial and one prospective cohort study, all other 12 studies had a retrospective cohort design. Our meta-analysis has yielded a pooled live birth rate per patient of 40% (95% CI: 29-51%; 14 studies included) and a pooled live birth rate per ET cycle of 17% (95% CI: 13-20%; 13 studies included). Also, the pooled clinical pregnancy achievement rate per ET cycle was estimated at 31% (95% CI: 25-36%; 12 studies included). Moreover, the pooled rate of pregnancy-induced hypertensive disorders per clinical pregnancy was estimated at 12% (95% CI: 1-31%; 8 studies included). No publication bias was found across all analyses. CONCLUSIONS: This study demonstrated promising pregnancy outcomes for OD in patients with TS. Further studies are essential to address not only the preferred techniques, but also the psychological, ethical, and societal implications of these complex procedures for these vulnerable populations. TRIAL REGISTRATION: This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the registration code CRD42023494273.

Increased miscarriage rate is associated with at least four components of metabolic syndrome in women with polycystic ovary syndrome undergoing in vitro fertilization or intracytoplasmic sperm injection embryo transfer cycle.

AIM: This study aimed to investigate the association between the components of metabolic syndrome (MetS) and reproductive outcomes in women with polycystic ovary syndrome (PCOS) undergoing their first in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) embryo transfer cycle. METHODS: This is a retrospective study that included 720 women with PCOS from January 2018 to December 2021. Anthropometric, biochemical, and reproductive data of the study subjects were collected from electronic medical record. Women with PCOS met <3, 3, and >3 criteria of MetS were classified in group 1, 2, and 3, respectively. RESULTS: The miscarriage rate in women with MetS was significantly higher than that in non-MetS group (23.2% vs. 14.2%, p = 0.03). There was a significant increasing trend in miscarriage rate from group 1 to group 3 (p for trend <0.05). The miscarriage rate in group 3 was significantly higher than that in group 1 (29.3% vs. 14.2%, p < 0.05). Logistic regression analyses showed that women with at least four components of MetS (group 3) were independently associated with a high risk of miscarriage, with the odds ratios and 95% confidence intervals for group 2 and 3 versus group 1 were 1.38 (0.67-2.82) and 2.46 (1.06-5.74), respectively (p for trend = 0.04). CONCLUSIONS: PCOS women accompanied with at least four diagnostic criteria of MetS is independently associated with increased miscarriage rate when undergoing their first IVF or ICSI cycle.

IVF and obstetric outcomes among women of advanced maternal age (≥45 years) using donor eggs.

RESEARCH QUESTION: Does very advanced maternal age (VAMA; age ≥45 years) influence obstetric outcomes among women using donor oocytes in IVF? DESIGN: This retrospective cohort study analysed data from a nationwide IVF registry in Taiwan, focusing on IVF cycles involving women aged 45 years and older using donated oocytes between 2007 and 2016. The study assessed cumulative live birth rates (CLBR) and secondary outcomes such as clinical pregnancy, miscarriage, live birth and twin pregnancy rates, alongside perinatal outcomes such as Caesarean section rates, pre-eclampsia, gestational diabetes and birthweight. RESULTS: The study included 1226 embryo transfer cycles from 745 women, with a stable live birth rate of about 40% across the study period. The CLBR was slightly lower in women aged 50 years and older (54.2%) compared with those aged 45-46 years (58.0%), but these differences were not statistically significant (P = 0.647). Secondary outcomes and perinatal outcomes did not significantly differ across age groups. Regression analysis suggested a non-significant trend towards a decrease in live birth rate and birthweight with increasing maternal age. The study also found that single-embryo transfer (SET) minimized the risk of twin pregnancies without significantly affecting live birth rates. CONCLUSIONS: IVF with donor oocytes remains a viable option for women of VAMA, with consistent live birth rates across age groups. However, the study underscores the importance of elective SET to reduce the risk of twin pregnancies and associated adverse outcomes. Further research is needed to explore the impact of other factors such as paternal age and embryo development stage on IVF success in this population.

Analysis of factors influencing pregnancy and its outcomes in women undergoing in vitro fertilization-embryo transfer/frozen embryo transfer cycles: A retrospective study.

The relationship between clinical outcomes and various factors influencing pregnancy was analyzed to provide reference data for patients and clinicians when selecting embryo transfer protocols. This was a retrospective study of 1309 transfer cycles between June 1, 2018, and May 1, 2023, in the Reproductive Medicine Center. Univariate analysis was performed on various factors that may have affected pregnancy outcomes, and further regression analysis was performed on those factors found by univariate analysis to correlate positively with clinical pregnancy outcomes. Finally, the embryo transfer schemes were compared based on the analysis results. The results showed that the stage of embryonic development significantly affected pregnancy outcomes after transplantation (P < .01, 95% confidence interval: 2.554 [1.958-3.332]). There was no significant difference in the pregnancy rate between 1 high-quality blastocyst transfer and 2 cleavage-stage embryos or blastocyst transfer (64.22% vs 70.11%, P = .439); however, the rate of multiple pregnancies after 1 high-quality blastocyst transfer was close to the rate of natural conception. These data show that the transfer of single high-quality blastocysts can significantly reduce the multiple pregnancy rate while ensuring an ideal pregnancy rate, which can be used as a reference for planning the first transplantation in patients with good prognoses.

Nomogram for predicting live birth in ovulatory women undergoing frozen-thawed embryo transfer.

BACKGROUND: Study objectives included the development of a practical nomogram for predicting live birth following frozen-thawed embryo transfers in ovulatory women. METHODS: Totally, 2884 patients with regular menstrual cycles in our center were retrospectively enrolled. In an 8:2 ratio, we randomly assigned patients to training and validation cohorts. Then we identified risk factors by multivariate logistic regression and constructed nomogram. Finally, receiver operating characteristic curve analysis, calibration curve and decision curve analysis were performed to assess the calibration and discriminative ability of the nomogram. RESULTS: We identified five variables which were related to live birth, including age, anti-Müllerian hormone (AMH), protocol of frozen-thawed embryo transfer (FET), stage of embryos and amount of high-quality embryos. We then constructed nomograms that predict the probabilities of live birth by using those five parameters. Receiver operating characteristic curve analysis (ROC) showed that the area under the curve (AUC) for live birth was 0.666 (95% CI: 0.644-0.688) in the training cohort. The AUC in the subsequent validation cohorts was 0.669 (95% CI, 0.625-0.713). The clinical practicability of this nomogram was demonstrated through calibration curve analysis and decision curve analysis. CONCLUSIONS: Our nomogram provides a visual and simple tool in predicting live birth in ovulatory women who received FET. It could also provide advice and guidance for physicians and patients on decision-making during the FET procedure.

Development of an IVF prediction model for donor oocytes: a retrospective analysis of 10 877 embryo transfers.

STUDY QUESTION: Can we develop a prediction model for the chance of a live birth following the transfer of an embryo created using donated oocytes? SUMMARY ANSWER: Three primary models that included patient, past treatment, and cycle characteristics were developed using Australian data to predict the chance of a live birth following the transfer of an embryo created using donated oocytes; these models were well-calibrated to the population studied, achieved reasonable predictive power and generalizability when tested on New Zealand data. WHAT IS KNOWN ALREADY: Nearly 9% of ART embryo transfer cycles performed globally use embryos created using donated oocytes. This percentage rises to one-quarter and one-half in same-sex couples and women aged over 45 years, respectively. STUDY DESIGN, SIZE, DURATION: This study uses population-based Australian clinical registry data comprising 9384 embryo transfer cycles that occurred between 2015 and 2021 for model development, with an external validation cohort of 1493 New Zealand embryo transfer cycles. PARTICIPANTS/MATERIALS, SETTING, METHODS: Three prediction models were compared that incorporated patient characteristics, but differed in whether they considered use of prior autologous treatment factors and current treatment parameters. We internally validated the models on Australian data using grouped cross-validation and reported several measures of model discrimination and calibration. Variable importance was measured through calculating the change in predictive performance that resulted from variable permutation. The best-performing model was externally validated on data from New Zealand. MAIN RESULTS AND THE ROLE OF CHANCE: The best-performing model had an internal validation AUC-ROC of 0.60 and Brier score of 0.20, and external validation AUC-ROC of 0.61 and Brier score of 0.23. While these results indicate ∼15% less discriminatory ability compared to models assessed on an autologous cohort from the same population the performance of the models was clearly statistically significantly better than random, demonstrated generalizability, and was well-calibrated to the population studied. The most important variables for predicting the chance of a live birth were the oocyte donor age, the number of prior oocyte recipient embryo transfer cycles, whether the transferred embryo was cleavage or blastocyst stage and oocyte recipient age. Of lesser importance were the oocyte-recipient parity, whether donor or partner sperm was used, the number of prior autologous embryo transfer cycles and the number of embryos transferred. LIMITATIONS, REASONS FOR CAUTION: The models had relatively weak discrimination suggesting further features need to be added to improve their predictive power. Variation in donor oocyte cohorts across countries due to differences such as whether anonymous and compensated donation are allowed may necessitate the models be recalibrated prior to application in non-Australian cohorts. WIDER IMPLICATIONS OF THE FINDINGS: These results confirm the well-established importance of oocyte age and ART treatment history as the key prognostic factors in predicting treatment outcomes. One of the developed models has been incorporated into a consumer-facing website (YourIVFSuccess.com.au/Estimator) to allow patients to obtain personalized estimates of their chance of success using donor oocytes. STUDY FUNDING/COMPETING INTEREST(S): This research was funded by the Australian government as part of the Medical Research Future Fund (MRFF) Emerging Priorities and Consumer Driven Research initiative: EPCD000007. L.R. declares personal consulting fees from Abbott and Merck, lecture fees from Abbott, receipt of an educational grant from Merck, past presidency of the Fertility Society of Australia & New Zealand and World Endometriosis Society and being a minor shareholder in Monash IVF Group (ASX:MVF). G.M.C. declares receipt of Australian government grant funding for the research study and the development and maintenance of the YourIVFSuccess website. O.F., J.N., and A.P. report no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Predicting the pregnancy outcome: Uncovering the link between ß-hCG, patient factors and live birth in IVF.

OBJECTIVE: The objectives of the study were to correlate live birth rate with the initial level of ß-hCG in all patients undergoing embryo transfer and develop a predictive model of live birth based on patients' and assisted reproductive technology (ART) characteristics. STUDY DESIGN: Single-center retrospective cohort study, including a total of 7587 positive first serum ß-hCG from women who performed fresh and frozen embryo transfer. Twenty-one variables related to patient characteristics and treatment modalities were analyzed by step-wise univariate analysis followed by multivariate analysis. The study included women between 18 and 45 years with a positive (>20 IU/L) serum ß-hCG between January 2011 and December 2020 while it excluded cycles from donation of gametes, PGT and >3 embryos transferred simultaneously. MAIN RESULTS AND THE ROLE OF CHANCE: Among the positive serum ß-hCG measurements 5085 (67.0 %) resulted in live births. ß-hCG was higher in the live birth group (691 IU/L) compared to the failed pregnancies group (304 IU/L) (p500 IU/mL provided a positive predictive value for live birth of 85.3 % (95 %CI 84.0-86.4). Failed pregnancies were more common among older maternal and paternal age. Previous abortions were more common in the failed pregnancies group (25.0 %) compared to the live birth group (19.4 %). The most common indication to treatment was male infertility, accounting for a larger portion in the live birth group (41.7 %). At multivariate analysis, the factors independently associated with live birth were: first serum ß-hCG (OR 1.35, 95 %CI 1.32-1.37), maternal age (OR 0.93, 95 %CI 0.91-0.95), previous abortions (OR 0.77, 95 % CI 0.68-0.88). The number of embryos transferred showed a positive correlation below a maternal age of 39 (<35 years old OR 1.60, CI 95 % 1.32-1.94; <39 years old OR 1.27 CI 95 % 1.09-1.47). The prediction model incorporating these four variables resulted in a sensitivity and specificity with an area under the ROC curve of 0.798. CONCLUSION: The study confirms the importance of the first value of ß-hCG and proposes a predictive model that takes into account maternal age, number of embryos transferred, and obstetric history, thereby aiding in couples' counseling and ultimately improve patients' care.

Fresh versus Frozen Embryo Transfer in In Vitro Fertilization/Intracytoplasmic Sperm Injection Cycles: A Systematic Review and Meta-Analysis of Neonatal Outcomes.

Background and Objectives: Although considerable research has been devoted to examining the distinctions between fresh and frozen embryo transfer regarding obstetric outcomes and rates of pregnancy success, there is still a scarcity of thorough analyses that specifically examine neonatal outcomes. The objective of our study was to provide an in-depth analysis of neonatal outcomes that occur after the transfer of fresh and frozen embryos (ET vs. FET) in IVF/ICSI cycles. Materials and Methods: Multiple databases (PubMed/MEDLINE, Cochrane Library, Web of Science, Wiley, Scopus, Ovid and Science Direct) were searched from January 1980 to February 2024. Two reviewers conducted the article identification and data extraction, meeting inclusion and exclusion criteria. The methodological quality was evaluated using the Newcastle-Ottawa Scale (NOS) or the revised Cochrane Risk of Bias Tool. The meta-analysis was performed using RevMan 5.4. Results: Twenty studies, including 171,481 participants in total, were subjected to qualitative and quantitative analyses. A significant increase in preterm birth rates was noted with fresh embryo transfer compared to FET in the overall IVF/ICSI population (OR 1.26, 95% CI 1.18-1.35, p < 0.00001), as well as greater odds of a low birth weight (OR 1.37, 95% CI 1.27-1.48, p < 0.00001) and small-for-gestational-age infants in this group (OR 1.81, 95% CI 1.63-2.00, p < 0.00001). In contrast, frozen embryo transfer can result in macrosomic (OR 0.59, 95% CI 0.54-0.65, p < 0.00001) or large-for-gestational-age infants (OR 0.64, 95% CI 0.60-0.69, p < 0.00001). No significant difference was observed regarding congenital malformations or neonatal death rates. Conclusions: This systematic review confirmed that singleton babies conceived by frozen embryo transfer are at lower risk of preterm delivery, low birthweight and being small for gestational age than their counterparts conceived by fresh embryo transfer. The data support embryo cryopreservation but suggest that elective freezing should be limited to cases with a proven indication or within the framework of a clinical study.

Comparison of pregnancy outcomes between 4th day morula and 5th day blastocyst after embryo transfer: a retrospective cohort study.

BACKGROUND: This study was designed to evaluate pregnancy outcomes between morulae transferred on day 4 (D4) and blastocysts transferred on day 5 (D5). METHODS: From September 2017 to September 2020, 1963 fresh transfer cycles underwent early follicular phase extra-long protocol for assisted conception in our fertility center were divided into D4 (324 cases) and D5 (1639 cases) groups, and the general situation and other differences of patients in both groups were compared. To compare the differences in pregnancy outcomes, the D4 and D5 groups were further divided into groups A and B based on single and double embryo transfers. Furthermore, the cohort was divided into two groups: those with live births (1116 cases) and those without (847 cases), enabling a deeper evaluation of the effects of D4 or D5 transplantation on assisted reproductive outcomes. RESULTS: In single embryo transfer, there was no significant difference between groups D4A and D5A (P > 0.05). In double embryo transfer, group D4B had a lower newborn birthweight and a larger proportion of low birthweight infants (P < 0.05). The preterm delivery rate, twin delivery rate, cesarean delivery rate, and percentage of low birthweight infants were lower in the D5A group than in the D5B group (P < 0.05). Analysis of factors influencing live birth outcomes further confirmed the absence of a significant difference between D4 and D5 transplantation in achieving live birth (P > 0.05). CONCLUSION: When factors such as working life and hospital holidays are being considered, D4 morula transfer may be a good alternative to D5 blastocyst transfer. Given the in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) success rate and risk of twin pregnancy, D4 morula transfer requires an adapted decision between single and double embryo transfer, although a single blastocyst transfer is recommended for the D5 transfer in order to decrease the twin pregnancy rate. In addition, age, endometrial thickness and other factors need to be taken into account to personalize the IVF program and optimize pregnancy outcomes.

Clinical data-based modeling of IVF live birth outcome and its application.

BACKGROUND: The low live birth rate and difficult decision-making of the in vitro fertilization (IVF) treatment regimen bring great trouble to patients and clinicians. Based on the retrospective clinical data of patients undergoing the IVF cycle, this study aims to establish classification models for predicting live birth outcome (LBO) with machine learning methods. METHODS: The historical data of a total of 1405 patients undergoing IVF cycle were first collected and then analyzed by univariate and multivariate analysis. The statistically significant factors were identified and taken as input to build the artificial neural network (ANN) model and supporting vector machine (SVM) model for predicting the LBO. By comparing the model performance, the one with better results was selected as the final prediction model and applied in real clinical applications. RESULTS: Univariate and multivariate analysis shows that 7 factors were closely related to the LBO (with P < 0.05): Age, ovarian sensitivity index (OSI), controlled ovarian stimulation (COS) treatment regimen, Gn starting dose, endometrial thickness on human chorionic gonadotrophin (HCG) day, Progesterone (P) value on HCG day, and embryo transfer strategy. By taking the 7 factors as input, the ANN-based and SVM-based LBO models were established, yielding good prediction performance. Compared with the ANN model, the SVM model performs much better and was selected as the final model for the LBO prediction. In real clinical applications, the proposed ANN-based LBO model can predict the LBO with good performance and recommend the embryo transfer strategy of potential good LBO. CONCLUSIONS: The proposed model involving all essential IVF treatment factors can accurately predict LBO. It can provide objective and scientific assistance to clinicians for customizing the IVF treatment strategy like the embryo transfer strategy.

Total blastocyst usable rate is a predictor of cumulative live birth rate in IVF cycles.

PURPOSE: Despite advances in IVF techniques, determining the prognostic factors influencing cumulative live birth rate (CLBR) remains crucial for optimizing outcomes. Among the various key performance indicators in the lab, blastulation rate, and more specifically Total Blastocyst Usable Rate (TBUR), has gained particular interest. In this study we aimed at determining if TBUR was significantly associated with CLBR. BASIC PROCEDURES: This monocentric retrospective case-control study was conducted in 317 consecutive IVF/ICSI cycles in 2014-2020 and leading to the formation of 3 usable blastocysts, including freeze all cycles. TBUR (usable blastocysts / 2PNs) was calculated and CLBR after 2-year follow up was recorded, including both fresh and frozen embyro transfers. CLBR was then compared between 2 groups according to TBUR (group 1: TBUR ≥50 % vs group 2: TBUR ≤30 %). MAIN FINDINGS: CLBR was significantly higher in group 1 than in group 2 (57 vs. 41 %, p = 0.02). Adjusted logistic regression showed a statistically significant relationship between CLBR and TBUR, with a significantly lower chance of achieving a live birth in group 2 than in group 1 (OR = 0.408 [0.17-0.96]; p = 0.04). PRINCIPAL CONCLUSIONS: Although the monocentric design and the arbitrary choice of thresholds for TBUR and number of blastocysts call for caution when generalizing the findings and advocates for external validation, our results illustrate that TBUR is a valuable prognostic factor of CLBR in IVF cycles which might serve as a tool for lab monitoring, cycle analysis by medical staff and patients' counselling. These results fit well within the P4 medicine concept (Predictive, Preventive, Personalized, and Participatory), and advocate for further research in order to improve embryo culture conditions.

Ongoing pregnancy rates in single euploid frozen embryo transfers remain unaffected by female age: a retrospective study.

RESEARCH QUESTION: Is female age a significant factor in the likelihood of an ongoing pregnancy in single euploid frozen embryo transfers (FET)? DESIGN: Retrospective study of 1923 single euploid FET cycles in 1464 women, either in a natural cycle or a hormone replacement therapy cycle. The primary outcome was the ongoing pregnancy rate (OPR). RESULTS: There were 990 (51.48%) ongoing pregnancies among 1923 included transfers. The OPR were 51.4%, 49.1%, 53.3% and 52.3% for women aged ≤35, >35-≤37, >37-≤40 and >40 years at oocyte retrieval (OCR), without a significant trend for decreasing OPR (P = 0.679). No significant differences in female age at embryo transfer (P = 0.609) and female age at OCR (P = 0.816) were found between the groups (ongoing pregnancy versus no pregnancy or miscarriage). Women who received good-quality embryos (P < 0.001), had a lower body mass index (BMI) (P < 0.001), had achieved at least one pregnancy previously (P < 0.001), and underwent natural cycle endometrial preparation (P < 0.001) were more likely to achieve an ongoing pregnancy. Multivariable regression analysis (adjusted for BMI, embryo quality and endometrial preparation) did not show a significant effect of female age at OCR on achieving an ongoing pregnancy. Compared with women aged ≤35 years, none of the age groups had significantly higher or lower OPR. A multinomial regression analysis showed that BMI, embryo quality and endometrial preparation were associated with miscarriage/no pregnancy versus ongoing pregnancy (P = 0.001, 0.001 and 0.001, respectively). Female age had no significant association with either outcome. CONCLUSIONS: Female age in itself does not have a substantial impact on the OPR in single euploid FET cycles, but the OPR is impacted significantly by embryo quality, BMI, previous parity, and a natural cycle endometrial preparation protocol.

The role of age and AMH on cumulative live birth rates over multiple frozen-thawed embryo transfer cycles: a study based on low prognosis patients of POSEIDON 3 and 4 groups.

BACKGROUND: Among the POSEIDON criteria, group 3 and group 4 have an expected low prognosis. For those patients with inadequate ovary reserve, embryo accumulated from consecutive oocyte retrieval cycles for multiple frozen-thawed embryo transfers (FET) has become more common. It is necessary to inform them of the pregnancy outcomes after single or multiple FET cycles before the treatment. However few studies about cumulative live birth rate (CLBR) for those with low prognosis have been reported. METHODS: This retrospective study included 4712 patients undergoing frozen embryo transfer cycles from July 2015 to August 2020. Patients were stratified as POSEIDON group 3, group 4, control 1 group (< 35 years) and control 2 group (≥ 35 years). The primary outcome is CLBRs up to six FET cycles and the secondary outcomes were LBRs per transfer cycle. Optimistic approach was used for the analysis of CLBRs and the depiction of cumulative incidence curves. RESULTS: Under optimistic model analyses, control 1 group exhibited the highest CLBR (93.98%, 95%CI 91.63-95.67%) within 6 FET cycles, followed by the CLBR from women in POSEIDON group 3(92.51%, 95%CI 77.1-97.55)was slightly lower than that in control 1 group. The CLBR of POSEIDON group 4(55% ,95%CI 39.34-70.66%)was the lowest and significantly lower than that of control 2 group(88.7%, 95%CI 80.68-96.72%). Further, patients in POSEIDON group 4 reached a CLBR plateau after 5 FET cycles. CONCLUSIONS: The patients of POSEIDON group 3 may not be considered as traditional "low prognosis" in clinical practice as extending the number of FET cycles up to 6 can archive considerably CLBR as control women. While for the POSEIDON group 4, a simple repeat of the FET cycle is not recommended after four failed FET cycles, some strategies such as PGT-A may be beneficial.

Influence of COVID-19 infection on early pregnancy outcomes in different periods around frozen embryo transfer.

PURPOSE: The study aimed to investigate the potential influence of COVID-19 infection on embryo implantation and early development in women undergoing frozen embryo transfer (FET), with a specific focus on infections occurring at different periods around FET. METHODS: A retrospective analysis was performed on women who had undergone FET during a period marked by a significant surge in COVID-19 infection in Shanghai. All enrolled women experienced their first documented COVID-19 infection around the time of FET, ensuring that infections did not occur prior to oocyte retrieval. Participants were categorized into six groups based on the timing of infection: uninfected, ≥ 60 days, < 60 days before FET, 0-14 days, 15-28 days, and 29-70 days after FET. Clinical outcomes were compared across these groups. RESULTS: The infection rate among the total of 709 cases was 78.28%. Infected individuals exhibited either asymptomatic or mild symptoms. The ongoing pregnancy rates for the first four groups were 40.7%, 44.4%, 40.5%, and 34.2% (P = 0.709) respectively, biochemical pregnancy rates (59.1% vs. 61.1% vs. 67.6% vs. 55.7%, P = 0.471) and clinical pregnancy rates (49.6% vs. 55.6% vs. 55.4% vs. 48.1%, P = 0.749), all showed no significant differences. Early spontaneous abortion rates across all six groups were 18.3%, 20.0%, 25.0%, 28.9%, 5.4%, and 19.0% respectively, with no significant differences (P = 0.113). Multivariable logistic analysis revealed no significant correlation between the infection and ongoing pregnancy. CONCLUSION: Asymptomatic or mild COVID-19 infections occurring around FET do not appear to have a significant adverse impact on early pregnancy outcomes.

The effects of endometrial thickness on outcomes of pregnancy following embryo transfer: A retrospective cohort.

OBJECTIVE: The safety of assisted reproductive technology can be assessed by examining birth weight as an outcome measure. The objective of this study was to evaluate the effect of endometrial thickness during embryo transfer on newborn birth weight and preterm labor. METHODS: We conducted a retrospective cohort study at the infertility department of a teaching hospital affiliated with a university of medical sciences. Eligible women were ≥18 years old and conceived a singleton pregnancy with embryo transfer and an endometrial thickness of ≥7 mm. None of the patients had diabetes, blood hypertension, and polycystic ovarian syndrome. We assessed maternal and newborn characteristics and perinatal pregnancy outcomes. RESULTS: In total, 100 eligible patients with a mean (SD) age of 32.8 (6.2) years were included. The mean endometrial thickness during embryo transfer was 9.1 (1.2) mm, and the mean birth weight was 3040.7 (565.3)g. There were no statistically significant associations between endometrial thickness and preterm labor (p=0.215) and between endometrial thickness and stillbirth or intra-uterine fetal death (p=0.880). However, after adjusting for confounding factors, the association of endometrial thickness with birth weight was statistically significant [b=124.6 (51.6), p=0.018]. CONCLUSIONS: Within the range of ≥7mm, endometrial thickness during embryo transfer is a predictor of newborn weight; however, it is not related to the risk of preterm labor, stillbirth, or intra-uterine fetal death.

Female smoking does not affect live birth rate after frozen thawed blastocyst transfer cycle.

PURPOSE: The development of vitrification and blastocyst culture have recently led to a rapidly growing number of single frozen thawed blastocyst transfer (FBT) cycles worldwide. Although the impact of female smoking on spontaneous fertility is well established, its effect on assisted reproductive technologies (ART) outcome is still controversial, and no study has specifically evaluated its effect on FBT cycles' outcome. METHODS: This retrospective study was conducted in all consecutive FBT cycles conducted between 2012 and 2021 in a single University-based ART centre. Endometrial preparation was standard and based on hormonal replacement therapy. One or two blastocysts were transferred according to couple's history and embryo quality. Female smoking status was recorded for each cycle, and the association between female smoking status and Live Birth Rate (LBR) after FBT cycle was evaluated with univariate and multivariate analysis. RESULTS: A total of 1537 FBT cycles performed in non-smoking women and 397 FBT cycles performed in smoking women were included in the analysis. No independent association between female smoking status and LBR in FBT cycles was found after logistic regression (OR=1.07 [0.79-1.45], p = 0.649). CONCLUSION: Our study suggests that female smoking might not impair endometrial receptiveness in non-stimulated FBT cycles. Further studies should nevertheless consider assessing more precisely the current smoking exposure.

Gestational carrier cycles: embryology trends, national guideline compliance, and resultant perinatal outcomes in the United States, 2014-2020.

BACKGROUND: The increased use of gestational carriers has expanded family-building opportunities for people and couples unable to carry pregnancies on their own. National American Society of Reproductive Medicine guidelines for gestational carriers have changed over time to reflect advances in reproductive technology and mounting evidence supporting the medical benefits associated with singleton gestations. OBJECTIVE: Assess changes in gestational carrier cycle practice patterns and resultant pregnancy outcomes in the United States in relation to changing national American Society of Reproductive Medicine guidelines, which changed in 2013 and 2017. STUDY DESIGN: This retrospective study used data from the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System and included all cycles that were reported from 2014-2020 involving an embryo transfer to a gestational carrier. Binomial regression models evaluated trends in preimplantation genetic testing for aneuploidy, American Society of Reproductive Medicine guideline adherence, number of embryos transferred, and pregnancy outcomes over time. RESULTS: Of the 40,177 gestational carrier transfer cycles from 2014-2020, there was a significant increase in frozen-thawed cycles (41.3% increase), use of assisted hatching (53.4% increase), intracytoplasmic sperm injection (50.0% increase), and preimplantation genetic testing for aneuploidy (155.7% increase). The likelihood of preimplantation genetic testing for aneuploidy was higher in 2020 than in 2014 for autologous oocyte transfers to gestational carriers, both for those aged ≥38 years (adjusted relative risk, 2.38 [95% confidence interval, 2.11-2.70]) and than those aged <38 years (adjusted relative risk, 2.85 [95% confidence interval, 2.58-3.15]). As preimplantation genetic testing for aneuploidy usage increased, single embryo transfer rose for both autologous (adjusted relative risk, 2.22 [95% confidence interval, 1.94-2.50]) and donor cycles (relative risk, 1.91 [95% confidence interval, 1.81-2.02]). This shift toward single embryo transfer corresponded with a decrease in multiple embryo transfer by 79.2% and subsequent decreases in multiple gestations by 68.8% in donor and 73.6% in autologous oocyte cycles from 2014-2020. Gestational carrier cycles remained highly adherent to changing American Society of Reproductive Medicine guidelines throughout the study period. Among live births, there was a 19.4% and 7.9% increase in term deliveries among donor and autologous oocyte cycles, respectively, from 2014 to 2020. CONCLUSION: Practice patterns have drastically changed throughout the study period, with major increases in the use of preimplantation genetic testing for aneuploidy, intracytoplasmic sperm injection, assisted hatching, and frozen transfers. In response to changing American Society of Reproductive Medicine guidelines, the use of multiple embryo transfers has decreased for gestational carrier cycles with subsequent decreases in multiple gestations and miscarriages and slight increases in live birth rates.

Medically Assisted Reproduction and Risk of Cancer Among Offspring.

Importance: Cancer is a leading cause of death among children worldwide. Treatments used for medically assisted reproduction (MAR) are suspected risk factors because of their potential for epigenetic disturbance and associated congenital malformations. Objective: To assess the risk of cancer, overall and by cancer type, among children born after MAR compared with children conceived naturally. Design, Setting, and Participants: For this cohort study, the French National Mother-Child Register (EPI-MERES) was searched for all live births that occurred in France between January 1, 2010, and December 31, 2021 (and followed up until June 30, 2022). The EPI-MERES was built from comprehensive data of the French National Health Data System. Data analysis was performed from December 1, 2021, to June 30, 2023. Exposure: Use of assisted reproduction technologies (ART), such as fresh embryo transfer (ET) or frozen ET (FET), and artificial insemination (AI). Main Outcomes and Measures: The risk of cancer was compared, overall and by cancer type, among children born after fresh ET, FET, or AI and children conceived naturally, using Cox proportional hazards regression models adjusted for maternal and child characteristics at birth. Results: This study included 8 526 306 children with a mean (SD) age of 6.4 (3.4) years; 51.2% were boys, 96.4% were singletons, 12.1% were small for gestational age at birth, and 3.1% had a congenital malformation. There were 260 236 children (3.1%) born after MAR, including 133 965 (1.6%) after fresh ET, 66 165 (0.8%) after FET, and 60 106 (0.7%) after AI. A total of 9256 case patients with cancer were identified over a median follow-up of 6.7 (IQR, 3.7-9.6) years; 165, 57, and 70 were born after fresh ET, FET, and AI, respectively. The overall risk of cancer did not differ between children conceived naturally and those born after fresh ET (hazard ratio [HR], 1.12 [95% CI, 0.96 to 1.31]), FET (HR, 1.02 [95% CI, 0.78 to 1.32]), or AI (HR, 1.09 [95% CI, 0.86 to 1.38]). However, the risk of acute lymphoblastic leukemia was higher among children born after FET (20 case patients; HR 1.61 [95% CI, 1.04 to 2.50]; risk difference [RD], 23.2 [95% CI, 1.5 to 57.0] per million person-years) compared with children conceived naturally. Moreover, among children born between 2010 and 2015, the risk of leukemia was higher among children born after fresh ET (45 case patients; HR, 1.42 [95% CI, 1.06 to 1.92]; adjusted RD, 19.7 [95% CI, 2.8 to 43.2] per million person-years). Conclusions and Relevance: The findings of this cohort study suggest that children born after FET or fresh ET had an increased risk of leukemia compared with children conceived naturally. This risk, although resulting in a limited number of cases, needs to be monitored in view of the continuous increase in the use of ART.