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.

Dichorionic diamniotic twin pregnancy after preimplantation genetic testing and single blastocyst transfer.

BACKGROUND: In addition to the potential for multiple pregnancies, natural conception occurring in preimplantation genetic testing (PGT) increases undesired genetic risk. Some studies showed that a dichorionic diamniotic twin pregnancy after a single blastocyst transfer could be caused by embryo splitting or concurrent spontaneous conception. CASE: We describe a patient undergoing PGT who had a dichorionic diamniotic twin pregnancy after single blastocyst transfer in a natural cycle. In this case, we recommended to determine genetic status of the twins by prenatal diagnosis. The results showed that karyotype, chromosome copy number variation, and parental ACAT1 variation of the twins were all normal and similar. To investigate the origin of pregnancy, we used the genotype data of single-nucleotide polymorphisms typical of genome-wide association studies. Dizygotic twins were inferred by robust estimation of kinship coefficients, which confirmed the occurrence of a spontaneous conception. CONCLUSIONS: This case strengthens the importance of genetic counseling to inform couples with reproductive genetic risk, such as those who undergo PGT, that intercourse should be avoided, especially in natural transfer cycles. Moreover, prenatal diagnosis remains essential and is strongly recommended to avoid genetic risks.

Clinical outcomes of single blastocyst transfer with machine learning guided noninvasive chromosome screening grading system in infertile patients.

BACKGROUND: Prospective observational studies have demonstrated that the machine learning (ML) -guided noninvasive chromosome screening (NICS) grading system, which we called the noninvasive chromosome screening-artificial intelligence (NICS-AI) grading system, can be used embryo selection. The current prospective interventional clinical study was conducted to investigate whether this NICS-AI grading system can be used as a powerful tool for embryo selection. METHODS: Patients who visited our centre between October 2018 and December 2021 were recruited. Grade A and B embryos with a high probability of euploidy were transferred in the NICS group. The patients in the control group selected the embryos according to the traditional morphological grading. Finally, 90 patients in the NICS group and 161 patients in the control group were compared statistically for their clinical outcomes. RESULTS: In the NICS group, the clinical pregnancy rate (70.0% vs. 54.0%, p < 0.001), the ongoing pregnancy rate (58.9% vs. 44.7%, p = 0.001), and the live birth rate (56.7% vs. 42.9%, p = 0.001) were significantly higher than those of the control group. When the female was ≥ 35 years old, the clinical pregnancy rate (67.7% vs. 32.1%, p < 0.001), ongoing pregnancy rate (56.5% vs. 25.0%, p = 0.001), and live birth rate (54.8% vs. 25.0%, p = 0.001) in the NICS group were significantly higher than those of the control group. Regardless of whether the patients had a previous record of early spontaneous abortion or not, the live birth rate of the NICS group was higher than that of the control group (61.0% vs. 46.9%; 57.9% vs. 34.8%; 33.3% vs. 0%) but the differences were not statistically significant. CONCLUSIONS: NICS-AI was able to improve embryo utilisation rate, and the live birth rate, especially for those ≥ 35 years old, with transfer of Grade A embryos being preferred, followed by Grade B embryos. NICS-AI can be used as an effective tool for embryo selection in the future.

Immediate versus delayed single blastocyst transfer following the first stimulated IVF cycle in the freeze-all strategy: a study protocol for a randomised controlled trial.

INTRODUCTION: In recent years, the use of frozen embryo transfers (FET) has rapidly increased following the freeze-all strategy due to the advantages of increased maternal safety, improved pregnancy rates, lower ectopic pregnancy rates and better obstetric and neonatal outcomes. Currently, there is still no good scientific evidence to support when to perform FET following a stimulated in vitro fertilisation (IVF) cycle in the freeze-all strategy. METHODS/ANALYSIS: This will be a randomised controlled trial. A total of 828 women undergoing their first FET following their first stimulated IVF cycle in the freeze-all strategy will be enrolled and randomised into one of the following groups according to a computer-generated randomisation list: (1) the immediate group, in which FET will be performed in the first menstrual cycle following the stimulated IVF cycle; or (2) the delayed group, in which FET will be performed at least in the second menstrual cycle following the stimulated IVF cycle. The primary outcome will be live birth, which is defined as the delivery of any infants at ≥22 gestational weeks with heartbeat and breath. ETHICS/DISSEMINATION: Ethical approval was granted by the Ethics Committee of Assisted Reproductive Medicine at the Shanghai JiAi Genetics & IVF Institute (JIAI E2019-15). Written informed consent will be obtained from each woman before any study procedure is performed, according to good clinical practice. The results of this trial will be disseminated in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT04371783.

Trade-off between double cleavage-stage embryos transfer and single blastocyst-stage embryo transfer in patients with few good quality embryos in antagonist cycles: a retrospective study using a propensity score matching analysis.

OBJECTIVE: This study aimed to compare the per OPU clinical outcomes for transfer of Day 3 double cleavage-stage embryos (DET) and Day 5 single blastocyst-stage (SBT) in patients with five or fewer good quality embryos on day 3 per occyte pick-up cycle (OPU) in antagonist cycles with consideration of blastocyst formation failure. METHODS: This was a retrospective, observational cohort study of 2,116 cases of OPU treated with antagonist protocol in the affiliated Chenggong Hospital of Xiamen University between January 2013 and December 2020. DET was performed in 1,811cycles and SBT was performed in 305 cycles. The DET group was matched to the SBT group by propensity score (PS) matching according to multiple maternal baseline covariates. After PS matching, there were 303 ET cycles in each group. The primary outcomes were the cumulative live birth rate (CLBR), cumulative multiple pregnancy rate(CMPR)per OPU and the number of ET to achieve live birth per OPU. Secondary outcomes were the percentage of clinical pregnancy(CPR), live birth rate(LBR), multiple pregnancy rate(MPR). RESULTS: Following PS mating, the CLBR was slightly higher (48.8% versus 40.3% ; P = 0.041) and the CMPR was significantly higher in the DET group compared to SBT group(44.2% versus 7.9%, P < 0.001). The CPR, LBR and MPR per fresh transfer were higher in DET group compared to SBT group(50.2% versus 28.7%; 41.3% versus 21.5%;29.6% versus 0%, P < 0.001). The number of ET to achieve live birth per OPU in SBT group was obiviously more than in DET group(1.48 ± 0.578 versus 1.22 ± 0.557 ,P < 0.001). CONCLUSION: With a marginal difference cumulative live birth rate, the lower live birth rate per fresh transfer and higher number of ET per OPU in the SBT group suggested that it might take longer time to achieve a live birth with single blastocyst strategy. A trade-off decision should be made between efficiency and safety.

Sex ratio shift after frozen single blastocyst transfer in relation to blastocyst morphology parameters.

The sex ratio shift was observed in peoples who underwent ART treatment. Moreover, there is limited evidence on differences in sex ratio between single frozen-thawed blastocyst morphology, insemination type and transfer days. So further research is needed in this area with regard to factors possibly affecting the sex ratio. Retrospective study based on multicenter including two large assisted reproduction centers in Shanghai and Wuhan in China. A total of 6361 singleton delivery offspring after frozen-thawed blastocyst transfer. Propensity score weighting and logistic regression models were used to estimate the associations between blastocyst morphology grading and child sex ratio. The main outcome measures is singleton sex ratio. In our study, the primary outcome measure was sex ratio which was calculated as the proportion of male newborns among all live births. Higher quality blastocysts resulted in a higher sex ratio than single poor-quality frozen-thawed blastocyst transfer. Among the three blastocyst morphological parameters of trophectoderm (TE), Grade A and B were significantly associated with a higher sex ratio than Grade C. The similar trend was observed in both IVF and ICSI treated subgroups. As compared with expansion (4 + 3), expansion degree 6 achieved a higher sex ratio in overall populations and IVF treated subgroup. Transferring blastocysts of day 6 had the highest sex ratio both in IVF group and ICSI group. A 6.95% higher sex ratio in transferring blastocysts of day 5 in IVF group than those in ICSI group. No significant association between inner cell mass degree and sex ratio was observed. However, as compared with IVF treatment, all morphology parameters achieved the similar or the biased sex ratio favoring female in ICSI treated subgroup. Quality of blastocysts was positively associated with sex ratio. TE score and expansion degree rather than ICM were significantly associated with sex ratio at birth. ICSI treatment promotes the biased sex ratio favoring female.

The effect of laser-assisted hatching on vitrified/warmed blastocysts: the ALADDIN randomized controlled trial.

OBJECTIVE: To evaluate whether laser-mediated assisted hatching (AH) performed on vitrified/warmed blastocysts before embryo transfer can improve live birth rate. DESIGN: The "pArtiaL zonA pelluciDa removal by assisteD hatchINg of blastocysts (ALADDIN)" is a 2-center comparative study with a parallel randomized controlled design. SETTING: University hospital. PATIENTS: Participants were recruited between September 2018 and November 2021. They were aged 18-39 years, underwent nondonor in vitro fertilization cycles, and were scheduled for elective single embryo transfer with vitrified/warmed blastocysts. Those with uterine abnormalities, body mass index of >35 kg/m2, severe male factor infertility, or performing preimplantation genetic testing were excluded. INTERVENTION: Assisted hatching was performed using a 1,480 nm diode laser, removing approximately one-third of the zona pellucida with continuous 0.2 ms pulses applied from the 1-5 o'clock positions. MAIN OUTCOME MEASURES: The primary outcome was the live birth rate. Secondary end points included clinical pregnancy, miscarriage, multiple pregnancies, preterm births, obstetric and neonatal complications, and congenital anomalies. RESULTS: Overall, 698 participants met the inclusion criteria and were randomized: 352 patients were assigned to the AH arm and 346 to the control arm. Of the participants, 105 (29.8%) and 101 (29.2%), respectively, achieved a live birth after treatment. The relative risk of live birth in patients with vitrified/warmed blastocysts treated with AH was 1.02 (95% confidence interval, 0.86-1.19). Exploratory subgroup analyses for women's age, recruiting centers, indications for in vitro fertilization, method of insemination, blastocyst quality, and days of blastocyst development failed to highlight any clinical situation that could benefit from AH in thawed blastocysts. CONCLUSION: In patients undergoing frozen embryo transfer with vitrified/warmed blastocysts, laser AH does not improve the live birth rate. Further studies are required to rule out milder but potentially interesting benefits in specific subgroups of patients. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03623659.

Single Euploid Embryo Transfer Outcomes After Uterine Septum Resection.

STUDY OBJECTIVE: To study pregnancy outcomes after single euploid embryo transfer (SEET) in patients who underwent prior uterine septum resection to those with uteri of normal contour, without Müllerian anomalies or uterine abnormalities including polyps or fibroids, and without a history of prior uterine surgeries. DESIGN: Retrospective cohort study. SETTING: Single academic affiliated center. PATIENTS: 60 cycles of patients with prior hysteroscopic uterine septum resection who underwent an autologous SEET between 2012 and 2020 were used as the investigational cohort. A 3:1 ratio propensity score matched control cohort of 180 single euploid embryo transfer cycles from patients without a history of uterine septa were used as the control group. INTERVENTIONS: No interventions administered. MEASUREMENTS AND MAIN RESULTS: Pregnancy, clinical pregnancy loss, ongoing clinical pregnancy, and live birth rates in patients with a history of uterine septum resection compared with matched patients without Müllerian anomalies or uterine surgeries. Patients with a prior uterine septum had significantly lower rates of chemical pregnancy (58.33% vs 77.2%, p = .004), implantation (41.67% vs 65.6%, p = .001), and live birth (33.33% vs 57.8%, p = .001) per transfer. No statistical difference in clinical pregnancy loss rates was found when comparing septum patients with controls (8.33% vs 7.8%, p = .89). CONCLUSION: Patients with a history of hysteroscopic resection who undergo in vitro fertilization are more susceptible to suboptimal clinical outcomes compared with patients with normal uteri. Early pregnancy loss rates in patients with a uterine septum are higher than in those without; however, after resection, the rates are comparable. Patients born with septate uteri require assessment of surgical intervention prior to SEET, and to optimize their reproductive outcomes.

BlastAssist: a deep learning pipeline to measure interpretable features of human embryos.

STUDY QUESTION: Can the BlastAssist deep learning pipeline perform comparably to or outperform human experts and embryologists at measuring interpretable, clinically relevant features of human embryos in IVF? SUMMARY ANSWER: The BlastAssist pipeline can measure a comprehensive set of interpretable features of human embryos and either outperform or perform comparably to embryologists and human experts in measuring these features. WHAT IS KNOWN ALREADY: Some studies have applied deep learning and developed 'black-box' algorithms to predict embryo viability directly from microscope images and videos but these lack interpretability and generalizability. Other studies have developed deep learning networks to measure individual features of embryos but fail to conduct careful comparisons to embryologists' performance, which are fundamental to demonstrate the network's effectiveness. STUDY DESIGN, SIZE, DURATION: We applied the BlastAssist pipeline to 67 043 973 images (32 939 embryos) recorded in the IVF lab from 2012 to 2017 in Tel Aviv Sourasky Medical Center. We first compared the pipeline measurements of individual images/embryos to manual measurements by human experts for sets of features, including: (i) fertilization status (n = 207 embryos), (ii) cell symmetry (n = 109 embryos), (iii) degree of fragmentation (n = 6664 images), and (iv) developmental timing (n = 21 036 images). We then conducted detailed comparisons between pipeline outputs and annotations made by embryologists during routine treatments for features, including: (i) fertilization status (n = 18 922 embryos), (ii) pronuclei (PN) fade time (n = 13 781 embryos), (iii) degree of fragmentation on Day 2 (n = 11 582 embryos), and (iv) time of blastulation (n = 3266 embryos). In addition, we compared the pipeline outputs to the implantation results of 723 single embryo transfer (SET) cycles, and to the live birth results of 3421 embryos transferred in 1801 cycles. PARTICIPANTS/MATERIALS, SETTING, METHODS: In addition to EmbryoScope™ image data, manual embryo grading and annotations, and electronic health record (EHR) data on treatment outcomes were also included. We integrated the deep learning networks we developed for individual features to construct the BlastAssist pipeline. Pearson's χ2 test was used to evaluate the statistical independence of individual features and implantation success. Bayesian statistics was used to evaluate the association of the probability of an embryo resulting in live birth to BlastAssist inputs. MAIN RESULTS AND THE ROLE OF CHANCE: The BlastAssist pipeline integrates five deep learning networks and measures comprehensive, interpretable, and quantitative features in clinical IVF. The pipeline performs similarly or better than manual measurements. For fertilization status, the network performs with very good parameters of specificity and sensitivity (area under the receiver operating characteristics (AUROC) 0.84-0.94). For symmetry score, the pipeline performs comparably to the human expert at both 2-cell (r = 0.71 ± 0.06) and 4-cell stages (r = 0.77 ± 0.07). For degree of fragmentation, the pipeline (acc = 69.4%) slightly under-performs compared to human experts (acc = 73.8%). For developmental timing, the pipeline (acc = 90.0%) performs similarly to human experts (acc = 91.4%). There is also strong agreement between pipeline outputs and annotations made by embryologists during routine treatments. For fertilization status, the pipeline and embryologists strongly agree (acc = 79.6%), and there is strong correlation between the two measurements (r = 0.683). For degree of fragmentation, the pipeline and embryologists mostly agree (acc = 55.4%), and there is also strong correlation between the two measurements (r = 0.648). For both PN fade time (r = 0.787) and time of blastulation (r = 0.887), there's strong correlation between the pipeline and embryologists. For SET cycles, 2-cell time (P < 0.01) and 2-cell symmetry (P < 0.03) are significantly correlated with implantation success rate, while other features showed correlations with implantation success without statistical significance. In addition, 2-cell time (P < 5 × 10-11), PN fade time (P < 5 × 10-10), degree of fragmentation on Day 3 (P < 5 × 10-4), and 2-cell symmetry (P < 5 × 10-3) showed statistically significant correlation with the probability of the transferred embryo resulting in live birth. LIMITATIONS, REASONS FOR CAUTION: We have not tested the BlastAssist pipeline on data from other clinics or other time-lapse microscopy (TLM) systems. The association study we conducted with live birth results do not take into account confounding variables, which will be necessary to construct an embryo selection algorithm. Randomized controlled trials (RCT) will be necessary to determine whether the pipeline can improve success rates in clinical IVF. WIDER IMPLICATIONS OF THE FINDINGS: BlastAssist provides a comprehensive and holistic means of evaluating human embryos. Instead of using a black-box algorithm, BlastAssist outputs meaningful measurements of embryos that can be interpreted and corroborated by embryologists, which is crucial in clinical decision making. Furthermore, the unprecedentedly large dataset generated by BlastAssist measurements can be used as a powerful resource for further research in human embryology and IVF. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Harvard Quantitative Biology Initiative, the NSF-Simons Center for Mathematical and Statistical Analysis of Biology at Harvard (award number 1764269), the National Institute of Heath (award number R01HD104969), the Perelson Fund, and the Sagol fund for embryos and stem cells as part of the Sagol Network. The authors declare no competing interests. TRIAL REGISTRATION NUMBER: Not applicable.

Recent clomiphene citrate exposure does not impact subsequent clinical outcomes in single euploid frozen embryo transfer cycles.

STUDY QUESTION: Do infertile couples who recently utilized clomiphene citrate (CC) for ovulation induction or ovarian stimulation (<90 days previously) followed by a single euploid embryo transfer (SEET) have lower implantation potential compared with patients who were not exposed to CC within 90 days before embryo transfer (ET)? SUMMARY ANSWER: There does not appear to be an association between recent CC exposure and lower implantation potential in patients who undergo a frozen embryo transfer (FET) of euploid embryos. WHAT IS KNOWN ALREADY: Clomiphene has been found to be associated with lower pregnancy rates when compared against other ovarian stimulation medications. The majority of published research about the effects of CC on implantation potential suggest an anti-estrogenic effect on the endometrium. Quality evidence and information about utilization of CC and its effect on implantation potential after euploid ETs is lacking in the literature. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study with propensity score matching was carried out. We included all patients that underwent an autologous SEET from September 2016 to September 2022 at a single academic-private ART center. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study group included patients that had utilized CC during either ovulation induction cycles and/or controlled ovarian stimulation at least 90 days before FET. A propensity score-matched control group of patients that were unexposed to CC within 90 days prior to SEET was used for comparisons. The primary outcome was positive pregnancy test (defined as a positive serum ß-hCG measured 9 days after ET), with other outcomes including clinical pregnancy, ongoing pregnancy, biochemical pregnancy loss, and clinical pregnancy loss rates per SEET. Multivariate regression analyses fitted with generalized estimating equations were utilized to analyze if there was an association between CC utilization and IVF outcomes. Furthermore, the study evaluated the cumulative effect of CC and endometrial receptivity in vivo and subsequent IVF outcomes. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 593 patients with utilization of CC in <90 days before ET were compared with 1779 matched controls. Positive pregnancy test rates were comparable among the control group and the CC exposed groups, respectively (74.3% versus 75.7%, P = 0.79), as were clinical pregnancy (64.0% versus 65.0%, P = 0.60), ongoing pregnancy (51.8% versus 53.2%, P = 0.74), biochemical pregnancy loss (15.7% versus 14.03%, P = 0.45), and clinical pregnancy loss rates were also comparable among cohorts (17.1% versus 18.1%, P = 0.71). No association was found between utilization of clomiphene and lower implantation rates (adjusted odds ratio 0.95, 95% CI 0.76-1.18). Also, no differences were observed in sub-analyses based on multiple CC utilization periods. Finally, no association was found between the number of consecutive cumulative clomiphene cycles and sub-optimal IVF outcomes. LIMITATIONS, REASONS FOR CAUTION: The study has inherent bias that originated from its retrospective design. Serum levels of CC were not measured and sample size for the sub-analyses was small. WIDER IMPLICATIONS OF THE FINDINGS: There does not appear to be an association between recent CC exposure and lower implantation potential in patients who undergo a FET of euploid embryos. This finding remains consistent, even in patients who undergo multiple, consecutive clomiphene cycles prior to ET. There were no long-term effects of CC on endometrial development and clinical characteristics examined in this study. Patients that utilized CC medication prior to a SEET cycle for either ovarian stimulation or ovulation induction, can be assured that there is no evidence of a residual effect of recent CC administration that could jeopardize their pregnancy probability. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for the realization of this study. A.C. is advisor and/or board member of Sema4 (stakeholder in data) and Progyny. The other authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Assessment of mitochondrial DNA viability ratio in day-4 biopsied embryos as an add-in to select euploid embryos for single embryo transfer.

The aim of this study was to assess mitochondrial DNA analysis as a predictor of the pregnancy potential of biopsied preimplantation embryos. The study included 78 blastomeres biopsied from day 4 cleavage stage euploid embryos. The embryo karyotype was confirmed by 24-chromosome preimplantation genetic testing for aneuploidies using the Illumina Next-Generation Sequencing (NGS) system. Mitochondria viability ratios (mtV) were determined from BAM files subjected to the web-based genome-analysis tool Galaxy. From this cohort of patients, 30.4% of patients (n = 34) failed to establish pregnancy. The mean mtV ratio [mean = 1.51 ± 1.25-1.77 (95% CI)] for this group was significantly (P < 0.01) lower compared with the embryo population that resulted in established pregnancies [mean = 2.5 ± 1.82-2.68 (95% CI)]. mtV multiple of mean (MoM) values were similarly significantly (P < 0.01) lower in blastocysts failing to establish pregnancy. At a 0.5 MoM cut-off, the sensitivity of mtV quantitation was 35.3% and specificity was 78.2%. The positive predictive value for an mtV value > 0.5 MoM was 41.4%. This study demonstrates the clinical utility of preimplantation quantification of viable mitochondrial DNA in biopsied blastomeres as a prognosticator of pregnancy potential.

A diagnosis of diminished ovarian reserve does not impact embryo aneuploidy or live birth rates compared to patients with normal ovarian reserve.

OBJECTIVE: To estimate the aneuploidy rates in young women with diminished ovarian reserve (DOR) before treatment and poor ovarian response (POR) postretrieval. DESIGN: Retrospective cohort study. SETTING: A single academically-affiliated fertility clinic. PATIENT(S): Autologous frozen embryo transfer cycles from December 2014 to June 2020 were reviewed. Demographic and clinical factors that impact outcomes were used for propensity score matching (PSM) in a ratio of 2:1 and 4:1 for preimplantation genetic testing for aneuploidy pre-cycle DOR and POR after stimulation, respectively. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Aneuploid rates, defined as the number of aneuploid blastocysts divided by the number of biopsied blastocysts per cycle. No euploid embryos to transfer, defined as all cohorts of embryos being aneuploid. RESULT(S): A total of 383 women diagnosed with DOR were compared with matched controls. Aneuploid rates did not differ significantly between the two groups (42.2% vs. 41.7%; RR = 1.06; 95% CI, 0.95-1.06). No differences were identified in live birth rates per transfer between women with and without DOR after euploid single-embryo transfers (56.0% and 60.5%, respectively). An additional PSM analysis to assess aneuploidy rates for patients with POR (<5 oocytes) vs. those without it, resulted in similar rates of aneuploidy between the two comparison groups (41.1% vs. 44%, R = 1.02; 95% CI, 0.91-1.14). The prevalence of cycles with "no euploid embryos" in the POR cohort was higher (26% vs. 13%); however, rates of cases with a single embryo available for biopsy were lower in the DOR group, relative to controls (11% vs. 31%). CONCLUSION(S): Young women diagnosed with DOR or POR exhibited equivalent aneuploidy rates and live birth rates per euploid embryo transfer in a large matched population, based on age, body mass index, and IVF cycle initiation. The lower percentage of cycles with no euploid embryo available for transfer in DOR and POR patients is because of the decreased total number of oocytes/developing embryos and not because of increased aneuploidy rates in these groups.

Correlation between an annotation-free embryo scoring system based on deep learning and live birth/neonatal outcomes after single vitrified-warmed blastocyst transfer: a single-centre, large-cohort retrospective study.

PROPOSE: Does an annotation-free embryo scoring system based on deep learning and time-lapse sequence images correlate with live birth (LB) and neonatal outcomes? METHODS: Patients who underwent SVBT cycles (3010 cycles, mean age: 39.3 ± 4.0). Scores were calculated using the iDAScore software module in the Vitrolife Technology Hub (Vitrolife, Gothenburg, Sweden). The correlation between iDAScore, LB rates, and total miscarriage (TM), including 1st- and 2nd-trimester miscarriage, was analysed using a trend test and multivariable logistic regression analysis. Furthermore, the correlation between the iDAScore and neonatal outcomes was analysed. RESULTS: LB rates decreased as iDAScore decreased (P < 0.05), and a similar inverse trend was observed for the TM rates. Additionally, multivariate logistic regression analysis showed that iDAScore significantly correlated with increased LB (adjusted odds ratio: 1.811, 95% CI: 1.666-1.976, P < 0.05) and decreased TM (adjusted odds ratio: 0.799, 95% CI: 0.706-0.905, P < 0.05). There was no significant correlation between iDAScore and neonatal outcomes, including congenital malformations, sex, gestational age, and birth weight. Multivariate logistic regression analysis, which included maternal and paternal age, maternal body mass index, parity, smoking, and presence or absence of caesarean section as confounding factors, revealed no significant difference in any neonatal characteristics. CONCLUSION: Automatic embryo scoring using iDAScore correlates with decreased miscarriage and increased LB and has no correlation with neonatal outcomes.

PGT-A: The biology and hidden failures of randomized control trials.

OBJECTIVE: Preimplantation Genetic Testing - Aneuploidy (PGT-A) for embryo selection has undergone significant advancements in the last 2 decades and yet many studies still fail to demonstrate any clinical benefits over traditional embryo morphology selection (Mo-S). To understand this conundrum, we performed a multi-center clinical study of PGT-A patients, where Mo-S and euploid selection (Eu-S) outcomes were directly compared. METHOD: All suitable blastocysts were biopsied and analyzed for chromosome copy number. Outcomes (positive beta hCG, implantation, ongoing pregnancy, and live birth rates) for Eu-S were compared to Mo-S using single embryo transfers. RESULTS: Compared to Eu-S embryos, Mo-S embryos resulted in significant reduction of outcomes for positive beta hCG (p = 0.0005), implantation (p = 0.0008), ongoing pregnancy (p = 0.0046), livebirth (p = 0.0112), babies per transfer (p = 0.0112), and babies per embryo transferred (p = 0.0112). Morphology selection resulted in patients of all age groups having non-euploid embryos chosen for transfer. Post-hoc evaluation of individual clinic performances showed variable transfer outcomes that could potentially confound the true benefits of PGT-A. CONCLUSION: Embryo chromosome status is central to improved embryo transfer outcomes and sole reliance on current morphology-based selection practices, without Eu-S, will always compromise outcomes. Often overlooked but a major effector of successful PGT-A outcomes are individual clinic performances.

Comparisons of benefits and risks of single embryo transfer versus double embryo transfer: a systematic review and meta-analysis.

BACKGROUND: Evidence referring to the trade-offs between the benefits and risks of single embryo transfer (SET) versus double embryo transfer (DET) following assisted reproduction technology are insufficient, especially for those women with a defined embryo quality or advanced age. METHODS: A systematic review and meta-analysis was conducted according to PRISMA guidelines. PubMed, EMBASE, Cochrane Library and ClinicalTrials.gov were searched based on established search strategy from inception through February 2021. Pre-specified primary outcomes were live birth rate (LBR) and multiple pregnancy rate (MPR). Odds ratio (OR) with 95% confidence interval (CI) were pooled by a random-effects model using R version 4.1.0. RESULTS: Eighty-five studies (14 randomized controlled trials and 71 observational studies) were eligible. Compared with DET, SET decreased the probability of a live birth (OR = 0.78, 95% CI: 0.71-0.85, P < 0.001, n = 62), and lowered the rate of multiple pregnancy (0.05, 0.04-0.06, P < 0.001, n = 45). In the sub-analyses of age stratification, both the differences of LBR (0.87, 0.54-1.40, P = 0.565, n = 4) and MPR (0.34, 0.06-2.03, P = 0.236, n = 3) between SET and DET groups became insignificant in patients aged ≥40 years. No significant difference in LBR for single GQE versus two embryos of mixed quality [GQE + PQE (non-good quality embryo)] (0.99, 0.77-1.27, P = 0.915, n = 8), nor any difference of MPR in single PQE versus two PQEs (0.23, 0.04-1.49, P = 0.123, n = 6). Moreover, women who conceived through SET were associated with lower risks of poor outcomes, including cesarean section (0.64, 0.43-0.94), antepartum haemorrhage (0.35, 0.15-0.82), preterm birth (0.25, 0.21-0.30), low birth weight (0.20, 0.16-0.25), Apgar1 < 7 rate (0.12, 0.02-0.93) or neonatal intensive care unit admission (0.30, 0.14-0.66) than those following DET. CONCLUSIONS: In women aged < 40 years or if any GQE is available, SET should be incorporated into clinical practice. While in the absence of GQEs, DET may be preferable. However, for elderly women aged ≥40 years, current evidence is not enough to recommend an appropriate number of embryo transfer. The findings need to be further confirmed.

Does fresh single embryo transfer outcome predict the result of a subsequent vitrified-warmed blastocyst of the same cohort?

Reflecting the current trends, the utilization of frozen-thawed transfer cycles has been steadily increasing worldwide; outcome predictors of these cycles are therefore a major research goal. Our aim was to investigate whether the outcome of a fresh single blastocyst transfer (SBT) can serve as a prognostic factor for the subsequent vitrified-warmed SBT originating from the same cohort. A retrospective cohort study was performed at a single unit. Non-donor fresh cycles were analyzed as predictors of the following vitrified-warmed cycle. Only SBTs were included. Cycles designated to a freeze-all policy and cycles involving pre-implantation genetic analysis were excluded. A total of 1127 vitrified-warmed single blastocyst cycles were included. The indications for artificial reproductive technologies were comparable across the study groups. Vitrified-warmed cycles following a live birth outcome in the fresh cycle were more likely to result in a clinical pregnancy than those following a fresh cycle, which failed to reach a live birth. The same trend was observed for live birth rate following vitrified-warmed transfer in the fresh cycle. After correcting for possible confounders, age and embryo quality were significantly correlated with the chance for a live birth, but the previous fresh cycle did not affect the results. We therefore conclude that after adjustment for age, embryo quality and number of previous oocyte retrieval cycles, the fresh cycle outcome was not a significant influential factor for the following vitrified-warmed cycle.

The position of the euploid blastocyst in the uterine cavity influences implantation.

RESEARCH QUESTION: Does the position of the euploid blastocyst in the uterine cavity upon transfer, measured as distance in millimetres (mm) from the fundus (DFF) to the air bubble, influence implantation potential? DESIGN: A total of 507 single/double euploid frozen embryo transfer (FET) cycles at blastocyst stage were included retrospectively between March 2017 and November 2018 at a single centre. The patients were on average 33.3 years old. The FET were performed in natural cycles (n = 151) or hormone replacement therapy cycles (n = 356). RESULTS: Of the 507 transfers, 370 (73.0%) resulted in a pregnancy, defined as human chorionic gonadotrophin concentration over 15 mIU/ml, and 341 (67.3%) in a clinical pregnancy, with an implantation rate of 62.0% and ongoing pregnancy rate of 59.6% (302/507). When comparing the number of embryos transferred, the pregnancy rate, clinical pregnancy rate and ongoing pregnancy rate were significantly higher after double-embryo transfer (DET) (P = 0.002: P < 0.001 and P = 0.002). The quality of the blastocyst in the single-embryo transfer group had a positive effect on the pregnancy rate (A versus B, P = 0.016; A versus C, P = 0.003) and clinical pregnancy rate (A versus C, P = 0.013). After performing a multivariate logistic regression analysis to consider the effect of all explanatory variables, a negative effect between DFF and pregnancy (P = 0.001), clinical pregnancy (P = 0.001) and ongoing pregnancy (P = 0.030) was found. When all variables remained constant, an increase of 1 mm of DFF changed the odds of pregnancy by 0.882, of clinical pregnancy by 0.891 and of ongoing pregnancy by 0.925. No significant effect of DFF was found on the miscarriage outcome (P = 0.089). CONCLUSIONS: The depth of blastocyst replacement inside the uterine cavity may influence the pregnancy, clinical pregnancy and ongoing pregnancy rates and should be considered as an important factor to improve the success of IVF cycles.

The precise determination of the window of implantation significantly improves ART outcomes.

The human endometrium is receptive to the embryo for a specific period of time known as the window of implantation (WOI). During this period, the endometrium shows a specific gene expression profile suitable for endometrial function evaluation. ER Map is a molecular tool able to accurately predict endometrial receptivity status by transcriptomic analysis. In this retrospective study, including 2256 subfertile patients undergoing ART treatment, the clinical value of precise WOI determination is studied in detail. Results obtained when single embryo transfers (sET) were scheduled either within the WOI timeframe as established by ER Map, or deviating from this WOI, are assessed and compared. Data obtained showed that 34.18% (771/2256) of patients had a displaced WOI. Analysis of ART outcomes showed significantly higher pregnancy rates in transfers scheduled within the WOI predicted compared to transfers that deviated more than 12h from this WOI (44.35% vs 23.08%, p < 0.001). The deviation from the WOI had also an impact on the progression of pregnancy, with a significant increase in pregnancy loss (~ twofold) observed in transfers that deviated more than 12h from the WOI predicted. These results indicate that the precise determination of the WOI and personalised embryo transfer can significantly improve clinical outcomes.

Effect of Day 3 and Day 5/6 Embryo Quality on the Reproductive Outcomes in the Single Vitrified Embryo Transfer Cycles.

Objective: To explore the live birth rate and neonatal outcome after single vitrified blastocyst transfer versus single vitrified cleavage-stage embryo transfer at different grades of embryo quality. Methods: A retrospective cohort study including 6077 single vitrified-thawed embryo transfer cycles was performed in the time-period from January 2013 to December 2018. Results: After controlling for potential confounding variables, there are 161% increased odds of a live birth after transfer of single good quality embryo at day 5, 152% increased odds of a live birth after transfer of single poor quality embryo at day 5, 60% increased odds of a live birth after transfer of single good quality embryo at day 6 compared with transfer of single good quality embryo at day 3. Results from the generalized estimated equation regression showed significant relationship of unadjusted birth weight with development stage of embryo and embryo quality (good quality embryo on day 5 vs. Good quality embryo on day 3:ß=108.55, SE=34.89, P=0.002; good quality embryo on day 6 vs. Good quality embryo on day 3:ß=68.80, SE=33.75, P=0.041). However, no significant differences were seen in birth weight between transfer single poor quality embryo on day 5, 6 and transfer single good quality embryo on day 3. Conclusion: A significant increase in live birth rate and birth weight after transfer of single good quality embryo on day 5 and day 6 compared with transfer of single good quality embryo on day 3 in the vitrified embryo transfer cycles.