The Impact of Embryo Quality on Pregnancy Outcomes in Single Day 5 versus Day 6 Euploid Blastocyst Transfer: A Retrospective Cohort Study.

BACKGROUND: Selecting embryos with the highest implantation potential is crucial for in vitro fertilization (IVF) success. Both the timing of blastulation, day 5 (D5) or D6, and the embryo quality have been suggested as influential factors in determining the clinical outcome of single euploid blastocyst transfers. However, evidence supporting the superiority of D5 over D6 blastocysts remains inconclusive. The aim of this study was to compare clinical outcomes following the transfer of euploid blastocysts with different quality and timing of blastulation. MATERIALS AND METHODS: A retrospective cohort study was conducted at our Assisted Reproductive Center, analyzing the outcome of 774 transfers with D5 euploids and 155 transfers with D6 euploids performed between January 2019 and February 2022. RESULTS: The live birth rate was significantly lower in the euploid D6 group compared to the euploid D5 group (38.71vs. 55.04%, P=0.001). The outcome was significantly influenced by the quality of the embryos. Live birth rates were 62.14 and 53.61% following transfers of D5 and D6 excellent embryos respectively, 45.18 and 32.21% following transfer of D5 and D6 good embryos but only 28.64 and 19.32% following transfer of D5 and D6 fair embryos. The outcome difference was statistically significant across embryo quality categories (P=0.001). The adjusted risk ratios (RR) of clinical outcomes indicated that excellent euploid D5 embryos consistently outperformed other types of embryo quality. CONCLUSION: The timing of blastulation and embryo quality are crucial factors in determining the success of single euploid blastocyst transfers. Excellent euploid D5 transfers yielded superior clinical outcomes, providing valuable insights for IVF teams and patients when selecting embryos to be transferred.

Association between pre-gravid body mass index and clinical outcomes in in vitro fertilization: a multicentered retrospective cohort study.

BACKGROUND: With the increasing incidence of obesity and the childbearing-age delay among women, a debate over obesity's impacts on pregnancy and neonatal outcomes becomes hot. The potential negative effects of obesity and aging on fertility lead to an idea, whether an obese female pursuing IVF treatment can benefit from an ideal BMI achieved over a long-time weight loss process at the cost of aging? We aimed to assess the association between body mass index (BMI) and clinical or neonatal outcomes in patients undergoing in vitro fertilization (IVF) treatment, for answering whether it is necessary to lose weight first for obese patients, particularly those at advanced age. METHODS: A retrospective cohort study was performed using multicentered data from China. The women were stratified into 5 groups in terms of pre-gravid BMI (kg/m2) with the WHO obesity standard (group 1: BMI < 18.5; group 2: 18.5 ≤ BMI < 23.0; group 3: 23.0 ≤ BMI < 25.0; group 4: 25.0 ≤ BMI < 30.0; group 5: BMI ≥ 30.0). The primary outcome was cumulative live birth rate (CLBR), and other clinical and neonatal outcomes were weighed as secondary outcomes. Multivariate logistic regression analyses were carried to evaluate the association between BMI and the CLBR, or between BMI and some neonatal outcomes. Furthermore, we implemented a machine-learning algorithm to predict the CLBR based on age and BMI. RESULTS: A total of 115,287 women who underwent first IVF cycles with autologous oocytes from January 2013 to December 2017 were included in our study. The difference in the CLBR among the five groups was statistically significant (P < 0.001). The multivariate logistic regression analysis showed that BMI had no significant impact on the CLBR, while women's age associated with the CLBR negatively. Further, the calculation of the CLBR in different age stratifications among the five groups revealed that the CLBR lowered with age increasing, quantitatively, it decreased by approximately 2% for each one-year increment after 35 years old, while little difference observed in the CLBR corresponding to the five groups at the same age stratification. The machine-learning algorithm derived model showed that BMI's effect on the CLBR in each age stratification was negligible, but age's impact on the CLBR was overwhelming. The multivariate logistic regression analysis showed that BMI did not affect preterm birth, low birth weight infant, small for gestational age (SGA) and large for gestational age (LGA), while BMI was an independent risk factor for fetal macrosomia, which was positively associated with BMI. CONCLUSIONS: Maternal pre-gravid BMI had no association with the CLBR and neonatal outcomes, except for fetal macrosomia. While the CLBR was lowered with age increasing. For the IVF-pursuing women with obesity plus advanced age, rather than losing weight first, the sooner the treatment starts, the better. A multicentered prospective study with a large size of samples is needed to confirm this conclusion in the future.

Lifetime induced abortions and live births. A 40-year historical cohort study.

OBJECTIVE: Little is known about whether induced abortions are associated with the final lifetime number of live births (life births). The objective of this study was to examine the association of number of life births with number of abortions a female has had in her lifetime. METHODS: In a national cohort design, we followed all Danish females from ages 15 to 44 years through the period 1977-2017 for induced abortions and live births. For each lifetime number of induced abortions, the average number of life births were assessed, and rates with 95% confidence limits calculated. RESULTS: The study included 409 497 females who completed 222 482 induced abortions and 831 742 live births. In 265 573 (64.9%) females who did not have any induced abortion, the average number of life births was 2.09 (95% CI 2.08-2.10). For females with 1 (23.4%), 2 (7.4%), 3 (2.6%), 4 (1.0%), and ≥5 (0.7%) induced abortions during their reproductive lifespan, the average number of life births was 1.88 (1.87-1.89), 1.99 (1.98-2.00), 2.09 (2.06-2.11), 2.13 (2.09-2.15), and 2.25 (2.21-2.29), respectively. The increase in number of life births in females with 1 to females with 5+ induced abortions was 4.7% for each additional induced abortion. CONCLUSION: We found number of induced abortions during a woman's reproductive lifespan to be positively correlated to the number of live births. This association is likely explained by a high fecundity in females with multiple pregnancies including induced abortions, and suggests that even several induced abortions do not compromise a woman's general reproductive end points.

Age related semen parameters and ICSI pregnancy outcomes of 8046 men in Turkey over a 9-year period.

The effect of paternal age on fertility remains unclear. This retrospective study aims to examine the impact of male age on semen parameters and the reproductive outcomes of men admitted to an infertility center over a 9-year period. A total of 8046 patients were included in the study. Men were divided into four age groups. The groups were evaluated for semen parameters and reproductive outcome. The 21-30 year group presented lower sperm concentrations in comparison to those aged 31-40 and 41-50, yet shared a similar concentration to those over 50 years of age. Moreover, grades A and B decreased significantly in men aged over 50 years. The highest progressive motility and normozoospermia were observed in the age group 31-40 years while men over 50 years of age had the highest rates of asthenozoospermia and oligoasthenozoospermia. Furthermore, live birth results were reported in 5583 of the patients who underwent intracytoplasmic sperm injection (ICSI) and were found highest between 31-40 years of age. To our knowledge, this is the largest study in Turkey focusing on male age-related semen parameters and ICSI pregnancy outcomes. The study demonstrates that age is a significant factor for semen quality and live birth.

Effect of time since vasectomy on live birth rate of TESE‒ICSI egg donation cycles and male-related prognostic factors.

BACKGROUND: Vasectomy is a widely used method of contraception. However, some men may have the desire to become biological fathers again after a period. OBJECTIVE: To explore the effect of time since vasectomy and different male comorbidities on live birth rates from intracytoplasmic sperm injection cycles using donated oocytes by using testicular spermatozoa obtained by testicular sperm extraction. MATERIALS AND METHODS: This was a retrospective study of 123 couples who underwent a testicular sperm extraction‒intracytoplasmic sperm injection cycle after vasectomy using donated oocytes. Subjects were divided into groups according to time since vasectomy and the male risk factor evaluated. The main outcomes measured were live birth rate per embryo transfer, per oocyte donation cycle, and per couple. We assessed the cumulative live birth rate according to the time since vasectomy and considered male comorbidities: body mass index, hypertension, diabetes mellitus, dyslipidemia, and smoking. RESULTS: The overall live birth rate per couple was 59.3% (50.6-68.0). Considering the number of embryo transfer and oocyte donation cycle, the live birth rates were 34.1% (27.8-40.4) and 44.5% (36.9-52.1), respectively. The live birth rate according to time since vasectomy was not statistically different between groups. Consequently, the cumulative live birth rate was similar between the different interval times when considering one to eight embryo transfers (p = 0.74). No statistical differences in live birth rate and cumulative live birth rate were found between groups clustered according to male body mass index, smoking, hypertension, and dyslipidemia. However, diabetic male patients had a significantly lower rate of live birth rate per couple (22.2% [4.94-49.4]) than non-diabetic patients did (62.7% [53.7-71.8]) (p = 0.03), but not in their cumulative live birth rate. CONCLUSIONS: The time since vasectomy seems to have no detrimental effects on the live birth rate and cumulative live birth rate in testicular sperm extraction‒intracytoplasmic sperm injection cycles with donated oocytes. Male diabetes negatively affects the overall live birth rate per couple, but not the cumulative live birth rate. These results could be useful for multidisciplinary patient-tailored counseling, regarding the chance of having a pregnancy and facilitating the decision-making process of the fertility specialists.

Trends and Outcomes of Fresh and Frozen Donor Oocyte Cycles in the United States.

OBJECTIVE: To examine trends, characteristics, and outcomes of donor oocyte embryo transfer cycles by original oocyte and resultant embryo state and determine whether oocyte state (fresh or frozen) is differentially associated with clinical pregnancy, live birth, and term, normal birthweight neonates among singleton live births. DESIGN: Retrospective cohort study SUBJECTS: Patients undergoing donor oocyte embryo transfer cycles in the United States reporting to National Assisted Reproductive Technology Surveillance System (NASS) from 2013-2020 EXPOSURE: Original donor oocyte and resultant embryo state (fresh or frozen) MAIN OUTCOME MEASURES: Annual numbers and proportions of total donor oocyte embryo transfer cycles stratified by oocyte and embryo state and single embryo transfer cycles resulting in live birth of term (≥37 weeks gestation), normal birthweight (≥2500g) singletons during 2013-2020. Rates of live birth and term, normal birthweight neonates among singleton live births for 2018-2020 are also reported. Relative risks (RR) examine associations between donor oocyte state and live birth and term, normal birthweight neonates among singleton live births resulting from donor oocyte embryo transfer cycles. RESULTS: From 2013-2020, there were 135,085 donor oocyte embryo transfer cycles, of which the proportions increased for frozen embryos (42.3% to 76.6%), fresh embryos using frozen donor oocytes (19.9% to 68.3%) and single embryo transfer (SET) (36.4% to 85.5%). During 2018-2020, there were 48,679 donor oocyte embryo transfer cycles. Rates of live birth were lower with frozen compared to fresh donor oocytes for both fresh (46.2%, 55.9%; aRR 0.83 [95% CI 0.79-0.87]) and frozen (41.3%, 45.8%; aRR 0.94 [95% CI 0.91-0.98]) embryo transfer cycles. Among singleton live births, rates of delivering a term, normal birthweight neonate were similar for frozen compared to fresh donor oocyte transfer cycles among fresh (77.3, 77.2%; aRR 1.01 [95% CI 0.98-1.03]) and frozen (75.6, 75.1%; aRR 1.02 [95% CI 0.99-1.04]) embryos. CONCLUSION: In this national study of donor oocyte embryo transfer cycles, frozen embryo transfers, fresh embryo transfers using frozen oocytes, and SET increased. Although frozen compared to fresh oocytes were associated with a slightly reduced rate of live birth, rates of term, normal birthweight neonates among singleton live births were comparable between donor oocyte states.

Effect of different endometrial preparation methods on pregnancy outcome of FET in women with a normal menstrual cycle.

Objective: This study aims to explore the relationship between different endometrial preparations and pregnancy outcomes among patients with regular ovulatory cycles in order to find the best endometrial preparation methods in the freeze-thaw embryo transfer (FET) cycle. Materials and Methods: This is a retrospective study to investigate FET pregnancy outcomes in women who had a regular menstrual cycle, were younger than 35 years old, and underwent a modified natural cycle (mNC), ovulation induction (OI), or a hormone replacement treatment (HRT) cycle. A total of 1071 frozen cycles were included for analysis. Results: The implantation rate and live birth rate (LBR) in the OI group show a significant difference when compared to the mNC and HRT groups (P < 0.01). After adjusting for confounding factors, the logistic regression analysis revealed that the number of embryos transferred, the embryo stage, and quality were significantly associated with clinical pregnancy rate and LBR. The LBR was additionally affected by the mode of the endometrial preparation; the OI cycle could increase LBR. Conclusions: Endometrial preparation methods affect the LBR in women with a regular menstrual cycle. The OI cycle had an advantage in the LBR of FET.

Evaluating risk factors in recurrent pregnancy loss: A prospective cohort study and its impact on live birth outcomes.

Recurrent pregnancy loss (RPL) affects 1-2 % of all couples trying to conceive and is a challenging heterogeneous condition. This study aimed to evaluate the prevalence and impact of various risk factors in patients suffering from RPL. We performed a prospective cohort study including patients at the tertiary RPL Unit in the Capital Region of Denmark between 1st January 2000 and 1st January 2023. The main outcome of the study was the first pregnancy after referral and whether the pregnancy was ongoing at least to the 22nd gestational week. A total of 2555 patients were included in the study, out of whom 1892 patients achieved a pregnancy after referral to the RPL Unit. This resulted in 1103 live births (58.3 %) and 718 pregnancy losses (37.9 %). Maternal age, BMI, smoking status and the number of prior pregnancy losses were negatively correlated with the likelihood of achieving pregnancy. Furthermore, maternal age, prior pregnancy losses, antiphospholipid syndrome (APS) and uterine malformations were associated with reduced birth rates. Patients with secondary RPL had a higher birth rate compared to those with primary RPL, and patients with APS treated with low-molecular-weight heparin (LMWH) demonstrated a significantly increased birth rate compared to untreated APS patients. These findings suggest that certain risk factors significantly impact the likelihood of achieving pregnancy and live birth following RPL, which can be used in patient guidance.

Hysteroscopic Endometrial Fundal Incision versus Hysteroscopy Only in Oocyte Recipients: A Randomized Controlled Trial Assessing The Reproductive Outcomes.

BACKGROUND: Endometrial scratching (ES) remains controversial regarding its potential effectiveness in improving pregnancy rates. The objective of the present study was to assess the impact of endometrial fundal incision (EFI) during hysteroscopy on reproductive outcomes in a population of oocyte recipients. MATERIALS AND METHODS: A randomized controlled trial was conducted between 2020 and 2023 at the Third Department of Obstetrics and Gynecology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki and "Assisting Nature Centre of Reproduction and Genetics". The study population consisted of women who underwent hysteroscopy randomly assigned in a 1:1 ratio to either EFI (one to three months before embryotransfer with donor oocytes) or no intervention throughout office hysteroscopy. Clinical pregnancy and live birth rates were the primary outcomes. RESULTS: After the exclusion of patients with intraoperative diagnosed endometrial pathology, a total of 124 women underwent randomization. The pregnancy test was positive in 79% (n=49/62) of the women in the EFI compared to 59.7% (n=37/62) in the hysteroscopy-only group (P=0.019), while the live birth rates did not differ between the two groups (58.1%, n=36/62 vs. 51.6%, n=32/62, P=0.470). CONCLUSION: EFI during hysteroscopy seems to improve pregnancy rates in oocyte recipients without intrauterine pathology, while live birth rates are not affected by the EFI. These results should be interpreted with caution before the implementation of EFI in the routine in vitro fertilization (IVF) practice (registration number: NCT04580056).

In vitro maturation of oocytes in light of ovarian mitochondrial improvement: effectiveness and safety.

In vitro maturation of oocytes (IVM) represents an assisted reproductive technique that involves the minimal or absence of ovarian stimulation and is beneficial to specific groups of patients. These may include women with polycystic ovarian syndrome and/or patients who need a fertility preservation option before undergoing gonadotoxic treatment. However, when IVM is applied in cases where it is not recommended, it can be considered as an add-on technique, as described by the ESHRE Guideline Group on Female Fertility Preservation. Interestingly, IVM has not been proven yet to be as effective as conventional IVF in the laboratory, in terms of clinical pregnancy and live birth rates, while concerns have been raised for its long-term safety. As a result, both safety and efficacy of IVM remain still questionable and additional data are needed to draw conclusions.

Vitrification preservation of good-quality blastocysts for more than 5 years reduces implantation and live birth rates.

STUDY QUESTION: Does vitrification cryopreservation of embryos for more than 5 years affect the pregnancy outcomes after frozen embryo transfer (FET)? SUMMARY ANSWER: Vitrification cryopreservation of good-quality blastocysts for more than 5 years is associated with a decrease in the implantation rate (IR) and live birth rate (LBR). WHAT IS KNOWN ALREADY: Previous studies have predominantly focused on embryos cryopreserved for relatively short durations (less than 5 years), yet the impact of extended cryopreservation duration on pregnancy outcomes remains a controversial issue. There is a relative scarcity of data regarding the efficacy and safety of storing embryos for 5 years or longer. STUDY DESIGN, SIZE, DURATION: This retrospective study involved 36 665 eligible vitrified-thawed embryo transfer cycles from 1 January 2016 to 31 December 2022, at a single fertility center in China. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were divided into three groups according to embryo storage time: Group 1 consisted of 31 565 cycles, with storage time of 0-2 years; Group 2 consisted of 4458 cycles, with a storage time of 2-5 years; and Group 3 included 642 cycles, with storage time exceeding 5 years. The main outcome measures were IR and LBR. Secondary outcome variables included rates of biochemical pregnancy, multiple pregnancy, ectopic pregnancy, and miscarriage, as well as neonatal outcomes. Reproductive outcomes were analyzed as binary variables. Multivariate logistic regression analysis was used to explore the effect of preservation time on pregnancy outcomes after correcting for confounding factors. In addition, we also assessed neonatal outcomes, such as large for gestational age (LGA) and small for gestational age (SGA). MAIN RESULTS AND THE ROLE OF CHANCE: IRs in the three groups (0-2, 2-5, and >5 years) were 37.37%, 39.03%, and 35.78%, respectively (P = 0.017), and LBRs in the three groups were 37.29%, 39.09%, and 34.91%, respectively (P = 0.028). After adjustment for potential confounding factors, compared with the 0-2 years storage group, prolonged embryo vitrification preservation time (2-5 years or >5 years) did not affect secondary outcomes such as rates of biochemical pregnancy, multiple pregnancy, ectopic pregnancy, and miscarriage (P > 0.05). But cryopreservation of embryos for more than 5 years reduced the IR (adjusted odds ratio (aOR) 0.82, 95% CI 0.69-0.97, P = 0.020) and LBR (aOR 0.76, 95% CI 0.64-0.91, P = 0.002). Multivariate stratified analysis also showed that prolonging the cryopreservation time of blastocysts (>5 years) reduced the IR (aOR 0.78, 95% CI 0.62-0.98, P = 0.033) and LBR (aOR 0.68, 95% CI 0.53-0.87, P = 0.002). However, no effect on cleavage embryos was observed (P > 0.05). We further conducted stratified analyses based on the number and quality of frozen blastocysts transferred, and the results showed that the FET results after transfers of good-quality blastocysts in the >5 years storage group were negatively affected. However, the storage time of non-good-quality blastocysts was not significantly associated with pregnancy outcomes. Regarding the neonatal outcomes (of singletons), embryo vitrification preservation time had no effect on preterm birth rates, fetal birth weight, or neonatal sex ratios. However, as the storage time increased, rates of SGA (5.60%, 4.10%, and 1.18%) decreased, while rates of LGA (5.22%, 6.75%, and 9.47%) increased (P < 0.05). After adjusting for confounding factors, the increase in LGA and the decrease in SGA were significantly correlated with the duration of storage time. LIMITATIONS, REASONS FOR CAUTION: This was a retrospective study using data from a single fertility center, even though the data had been adjusted, our findings still need to be validated in further studies. WIDER IMPLICATIONS OF THE FINDINGS: With the full implementation of the two-child policy in China, there may be more patients whose embryos have been frozen for a longer time in the future. Patients should be aware that the IR and LBR of blastocysts are negatively affected when the cryopreservation time is longer than 5 years. Couples may therefore consider shortening the time until FET treatment. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Nature Science Foundation of China (No. 82101672), Science and Technology Projects in Guangzhou (No. 2024A03J0180), General Guidance Program for Western Medicine of Guangzhou Municipal Health Commission (No. 20231A011096), and the Medical Key Discipline of Guangzhou (2021-2023). None of the authors have any conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Effectiveness and safety of GnRH antagonist originator and generic in real-world clinical practice: a retrospective cohort study.

Objective: This study aims to determine whether the live birth rates were similar between GnRH antagonist original reference product Cetrotide® and generic Ferpront®, in gonadotropin-releasing hormone (GnRH) antagonist protocol for controlled ovarian stimulation (COS). Methods: This retrospective cohort study investigates COS cycles utilizing GnRH antagonist protocols. The research was conducted at a specialized reproductive medicine center within a tertiary care hospital, spanning the period from October 2019 to October 2021. Within this timeframe, a total of 924 cycles were administered utilizing the GnRH antagonist originator, Cetrotide® (Group A), whereas 1984 cycles were undertaken using the generic, Ferpront® (Group B). Results: Ovarian reserve markers, including anti-Mullerian hormone, antral follicle number, and basal follicular stimulating hormone, were lower in Group A compared to Group B. Propensity score matching (PSM) was performed to balance these markers between the groups. After PSM, baseline clinical features were similar, except for a slightly longer infertile duration in Group A versus Group B (4.43 ± 2.92 years vs. 4.14 ± 2.84 years, P = 0.029). The duration of GnRH antagonist usage was slightly longer in Group B than in Group A (6.02 ± 1.41 vs. 5.71 ± 1.48 days, P < 0.001). Group B had a slightly lower number of retrieved oocytes compared to Group A (14.17 ± 7.30 vs. 14.96 ± 7.75, P = 0.024). However, comparable numbers of usable embryos on day 3 and good-quality embryos were found between the groups. Reproductive outcomes, including biochemical pregnancy loss, clinical pregnancy, miscarriage, and live birth rate, did not differ significantly between the groups. Multivariate logistic regression analyses suggested that the type of GnRH antagonist did not independently impact the number of oocytes retrieved, usable embryos, good-quality embryos, moderate to severe OHSS rate, clinical pregnancy, miscarriage, or live birth rate. Conclusion: The retrospective analysis revealed no clinically significant differences in reproductive outcomes between Cetrotide® and Ferpront® when used in women undergoing their first and second COS cycles utilizing the GnRH antagonist protocol.

Effects of high-normal fasting blood glucose on ART outcomes of frozen-thawed single blastocyst transfer in women with normal BMI.

PURPOSE: This retrospective cohort study aims to investigate whether high-normal fasting blood glucose (FBG) affects assisted reproductive technology (ART) outcomes undergoing single blastocyst frozen-thawed embryo transfer (FET) cycles in women with normal body mass index (BMI). METHODS: 944 women with normal BMI and FBG levels undergoing single blastocyst FET cycles were enrolled. Based on the median of FBG (4.97 mmol/L, 1 mmol/L = 18 mg/dL), the subjects were categorized into the low-normal group (3.90 ≤ FBG ≤ 4.97 mmol/L, n = 472) and the high-normal group (4.97 < FBG < 6.10 mmol/L, n = 472). Multivariable logistic regression and receiver operating characteristic (ROC) were used to analyze the relationship between high-normal FBG and ART outcomes. PRIMARY OUTCOME: live birth rate (LBR). RESULTS: LBR was significantly lower in the high-normal group than in the low-normal group (36.8% vs. 45.1%, p = 0.010), and the miscarriage rate was considerably higher than that in the low-normal group (23.9% vs. 16.5%, p = 0.041). High-normal FBG of female was an independent predictor of live birth (adjusted OR:0.747, 95% CI: 0.541-0.963, p = 0.027) and miscarriage (adjusted OR:1.610, 95% CI: 1.018-2.547, p = 0.042). ROC analyses showed that the cut-off values of FBG (endpoints: live birth and miscarriage) were 5.07 mmol/L, and 5.01 mmol/L, respectively. CONCLUSIONS: In women with normal BMI, high-normal FBG is an independent risk factor for lower LBR and higher miscarriage rate in single blastocyst FET cycles. Attention to preconception FBG monitoring in this particular population may allow early intervention to improve ART outcomes.

Exposure to golimumab during pregnancy: Results from the Company's global safety database.

Data on the use of golimumab (GLM) during pregnancy are limited. This study evaluated pregnancy outcomes in women treated with GLM during pregnancy. Cumulative data on GLM-exposed pregnancies from the Company's global safety database (GSD) are summarized. Cases were medically confirmed maternal exposures to GLM during pregnancy or within 3 months prior to conception with a reported pregnancy outcome. Pregnancy outcomes (e.g., live births) and congenital anomalies in prospectively reported cases (i.e., pregnancy outcome not known when first reported to the company) are presented in a descriptive manner. As of May 31, 2022, 261 prospectively reported pregnancies exposed to GLM were reported in the GSD: 214 (82.0%) live births (including six sets of twins), 31 (11.9%) spontaneous abortions (including one set of twins), 13 (5.0%) induced/elective abortions, 2 (0.8%) reported intrauterine death/still birth, and 1 (0.4%) fetal adverse event in an ongoing pregnancy. The majority of pregnancies had exposure to GLM at least in the first trimester of pregnancy. In total, seven congenital anomalies (7/261; 2.7%) were reported. Of these seven congenital anomalies, five were considered major according to EUROCAT classification version 1.4. Among the five prospectively reported congenital anomalies noted in live births (5/214; 2.3%), four were classified as major (4/214; 1.8%). The rates of adverse pregnancy outcomes and major congenital anomalies in prospectively reported pregnancy cases with exposure to GLM in the Company's GSD were consistent with published background rates for the general population.

Impact of inclusion of a poor-quality embryo with a good-quality embryo on pregnancy outcomes in vitrified-warmed blastocyst transfers.

RESEARCH QUESTION: Does the co-transfer of a good-quality embryo and a poor-quality embryo influence pregnancy outcomes in comparison to the transfer of a single good-quality embryo in vitrified-warmed blastocyst transfer cycles? DESIGN: This retrospective cohort study involved a total of 11,738 women who underwent IVF/intracytoplasmic sperm injection cycles and vitrified-warmed blastocyst transfer at a tertiary-care academic medical from January 2015 to June 2022. The study population was categorized into two groups: single-blastocyst transfer (SBT; participants who underwent single good-quality embryo transfer, n = 9338) versus double-blastocyst transfer (DBT; participants who underwent transfers with a poor and a good-quality embryo, n = 2400). RESULTS: The live birth rate (LBR) was significantly higher in the DBT group in comparison with the SBT group (65.6% versus 56.3%, P < 0.001). Multivariable logistic regression analysis showed that DBT was an independent predictor for LBR with a strong potential impact (adjusted odds ratio 1.55, 95% confidence interval 1.41-1.71; P < 0.001). However, the multiple birth rate was significantly higher in the good-quality embryo and poor-quality embryo group compared with patients undergoing a single good-quality embryo transfer (41.4% versus 1.8%; P < 0.001). CONCLUSIONS: In vitrified-warmed blastocyst transfer cycles, LBR was higher following DBT with one good-quality and one poor-quality embryo compared with SBT. However, this was at the expense of a marked increase in the likelihood of multiple gestations. Physicians should still balance the benefits and risks of double-embryo transfer.

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.

The density of the inner cell mass is a new indicator of the quality of a human blastocyst: a valid supplement to the Gardner scoring system.

STUDY QUESTION: Can the density of the inner cell mass (ICM) be a new indicator of the quality of the human blastocyst? SUMMARY ANSWER: The densification index (DI) developed in this study can quantify ICM density and provide positive guidance for ploidy, pregnancy, and live birth. WHAT IS KNOWN ALREADY: In evaluating the quality of ICM, reproductive care clinics still use size indicators without further evaluation. The main disadvantage of this current method is that the evaluation of blastocyst ICM is relatively rough and cannot meet the needs of clinical embryologists, especially when multiple blastocysts have the same ICM score, which makes them difficult to evaluate further. STUDY DESIGN, SIZE, DURATION: This observational study included data from 2272 blastocysts in 1991 frozen-thawed embryo transfer (FET) cycles between January 2018 to November 2021 and 1105 blastocysts in 430 preimplantation genetic testing cycles between January 2019 and February 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS: FET, ICSI, blastocyst culture, trophectoderm biopsy, time-lapse (TL) monitoring, and next-generation sequencing were performed. After preliminary sample size selection, the 11 focal plane images captured by the TL system were normalized and the spatial frequency was used to construct the DI of the ICM. MAIN RESULTS AND THE ROLE OF CHANCE: This study successfully constructed a quantitative indicator DI that can reflect the degree of ICM density in terms of fusion and texture features. The higher the DI value, the better the density of the blastocyst ICM, and the higher the chances that the blastocyst was euploid (P < 0.001) and that pregnancy (P < 0.001) and live birth (P = 0.005) were reached. In blastocysts with ICM graded B and blastocysts graded 4BB, DI was also positively associated with ploidy, pregnancy, and live birth (P < 0.05). ROC analysis showed that combining the Gardner scoring system with DI can more effectively predict pregnancy and live births, when compared to using the Gardner scoring system alone. LIMITATIONS, REASONS FOR CAUTION: Accurate calculation of the DI value places high demands on image quality, requiring manual selection of the clearest focal plane and exposure control. Images with the ICM not completely within the field of view cannot be used. The association between the density of ICM and chromosomal mosaicism was not evaluated. The associations between the density of ICM and different assisted reproductive technologies and different culture conditions in embryo laboratories were also not evaluated. Prospective studies are needed to further investigate the impact of ICM density on clinical outcomes. WIDER IMPLICATIONS OF THE FINDINGS: ICM density assessment is a new direction in blastocyst assessment. This study explores new ways of assessing blastocyst ICM density and develops quantitative indicators and a corresponding qualitative evaluation scheme for ICM density. The DI of the blastocyst ICM developed in this study is easy to calculate and requires only TL equipment and image processing, providing positive guidance for clinical outcomes. The qualitative evaluation scheme of ICM density can assist embryologists without TL equipment to manually evaluate ICM density. ICM density is a simple indicator that can be used in practice and is a good complement to the blastocyst scoring systems currently used in most centers. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Key Research & Development Program of China (2021YFC2700603). The authors report no financial or commercial conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Clinical outcomes of vitrified-warmed autologous oocyte cycles with 15-year follow-up at a single UK centre: consistent and predictable results.

RESEARCH QUESTION: What were the clinical outcomes from 332 autologous vitrified- warmed oocyte cycles derived from 3182 elective autologous oocyte freeze cycles carried out between 2008 and 2022 in a single-centre series? DESIGN: In this retrospective observational study, outcomes in 299 patients returning to use their frozen oocytes between 2015 and 2023 were analysed. RESULTS: A total of 3328 elective oocyte vitrification cycles were performed in 2280 patients. The return rate to use oocytes was 14% (299/2171). Mean ages were 37.6 years at storage and 40 at warming. Ninety-three clinical pregnancies and 77 healthy live births were recorded. The live birth rate (LBR) was 24% (39/163) per fresh transfer and 17% (39/227) per embryo transferred. Stratified by age at freezing, the LBR per embryo transferred was 26% (12/47) in participants under 35 years, 20% (24/118) in those 35-39 years and 5% (3/62) in those 40+ years. Frozen embryo transfers (FET) achieved a 30% (24/80) LBR per embryo transfer and a 27% (24/90) LBR per embryo transferred. PGT-A for embryo selection doubled the LBR compared with FET from an untested embryo after one attempt (40% versus 21%). In patients aged over 40 years, the cumulative LBR reached 42% per patient in euploid FET. CONCLUSION: The proportion of patients who returned to use their stored oocytes and the clinical outcomes were consistent with other recent reports and challenges the prevalent critical narrative regarding elective oocyte freezing for fertility preservation. The results are now comparable to routine IVF. Not everyone who returns to use their oocytes will conceive, but for those choosing to preserve their fertility, oocyte freezing can provide reproducible and reassuring results.