Blastocyst Stage Embryo Transfer Research Articles

P-110 Live birth of blastocyst culture in women with previous poor blastocyst formation: a cohort study

Abstract Study question Do cumulative live birth rates(CLBRs) in the second cycle differ between blastocyst-stage and cleavage-stage transfer in women with low blastocyst progression during initial IVF ? Summary answer The CLBRs following subsequent oocyte retrievals were comparable for extended culture with blastocyst-stage embryo versus cleavage-stage transfers. What is known already Fresh blastocyst-stage embryo transfer increases live birth rates when compared to cleavage- stage embryo transfer in women with good prognosis. However, it remains unclear whether a blastocyst-culture approach can still be considered for women with a history of failed or reduced blastocyst formation. Study design, size, duration A retrospective cohort study evaluating outcomes of the second IVF/ICSI in women who had a history of poor blastocyst development in their first-time retrievals at a single fertility center from September 2019 to December 2021. Women fulfilled embryo quality criteria of having at least two good-quality cleavage-stage embryos (graded 1-2) on day 3 were included for analysis. Participants/materials, setting, methods A total of 396 patients were analyzed and categorized into two groups. Group D5/6: Extending culture of all embryos to blastocyst-stage in vitro followed by blastocyst transfer; Group D3: transfer or cryopreservation of one or two of the highest quality cleavage-stage embryo(s) on Day3.The main outcome measure was the CLBR per oocyte retrieval.Multivariable logistic regression analyses were used to assess the association between two culture approaches and live birth outcomes after adjusting for possible confounders. Main results and the role of chance The CLBRs (57.01% versus 49.48%) were numerically higher in women in D5/6 group (N = 107) than those in D3 group (N = 289) although the difference was attenuated and did not reach statistical significance after controlling for confounders (aOR: 1.27, 95%CI 0.78, 2.07,P=0.345). All subgroup analyses showed similar conclusions as the main model, even restricting on women with a limited number of quality embryos 3 days post-fertilization. Among cycles with only 2 or 3 good-quality cleavage embryos, Day3 transfers were still associated with lower CLBR compared to all blastocyst culture and transfer (aOR 0.66, 95% CI 0.51-0.87). Limitations, reasons for caution The retrospective nature of the present study, alongside the selection bias towards blastocyst culture, may predispose to the risk of residual confounding. The cohort of women characterized by previous failed or reduced blastocyst formation was comparatively small. Larger prospective studies focusing on the unique group are still needed. Wider implications of the findings Even in poor prognosis IVF patients with a history of poor blastocyst formation and/ or blastulation failure, all blastocyst culture and transfer can still be considered when at least two good-quality embryos are available at day 3. These findings are clinically relevant and require additional investigation. Trial registration number Not Applicable

P-770 Health outcomes of taiwanese infants after different embryo stages in both fresh and frozen transfer procedures

Abstract Study question Does freezing embryos have any effects on neonatal and postnatal health? Does extended embryo culture have any impact on these health outcomes? Summary answer frozen embryo transfer (FET) infants were more likely be large gestational age, but with lower odds of recurrent upper respiratory infection and dermatitis. What is known already Infants born from frozen embryo transfers tend to have higher birth weights and are less likely to be small for gestational age. There are no notable variations in congenital malformations or child development. However, there’s a lack of long-term follow-up data. Study design, size, duration In this retrospective cohort study conducted in Taiwan, data from the national assisted reproductive technology (ART) database spanning from January 1st, 2013, to December 31st, 2017, was utilized. The study categorizes cases into fresh and frozen embryo transfer groups, with additional subdivisions based on cleavage and blastocyst stage transfers. Singletons born in each group were then linked to the National Health Insurance Database for follow-up on health conditions until December 13th, 2018. Participants/materials, setting, methods We collected data on singleton births resulting from assisted reproductive technology procedures performed in Taiwan from January 1st, 2013, to December 31st, 2017. Our analysis included 10,669 eligible infants. We investigated factors such as gestational age, birth weight, and various systemic diseases, encompassing neurological disorders, facial and eye abnormalities, cardiovascular diseases, respiratory disease, gastrointestinal disorders, renal system disorders, musculoskeletal disorders, skin and submucous disorders, chromosomal abnormalities, infections, and birth injuries. Main results and the role of chance Compared to infants conceived from fresh embryos, those born to mothers who underwent frozen embryo transfer (FET) were more likely to be large for gestational age (OR 1.63, 95% CI 1.30-2.04 for blastocyst and OR 1.69, 95% CI 1.36-2.10 for cleavage stage), and to have a neonatal birth weight of ≥ 4000g (OR 1.88, 95% CI 1.15-3.07 for blastocyst and OR 2.64, 95% CI 1.63-4.28 for cleavage stage). However, they were less likely to be small for gestational age (OR 0.68, 95% CI 0.56-0.82 for blastocyst and OR 0.68, 95% CI 0.56-0.82 for cleavage stage). Infants born from frozen embryo transfers also experienced lower odds of recurrent upper respiratory infection (OR 0.72, 95% CI 0.60-0.86 for blastocyst and OR 0.60, 95% CI 0.52-0.69 for cleavage stage), as well as eczema and dermatitis (OR 0.75, 95% CI 0.62-0.91 for blastocyst and OR 0.75, 95% CI 0.62-0.91 for cleavage stage). There was no observed effect on infant health between blastocyst and cleavage stage embryo transfers. Limitations, reasons for caution Our retrospective study design may not possess the same level of rigor as a randomized controlled trial (RCT). The follow-up period in our study ranged from 1 to 5 years, and some diseases may not manifest within this short-term timeframe, necessitating longer-term tracking for more comprehensive observation. Wider implications of the findings The result highlights the potential benefits of FET in reducing the risk of low birth weight. The observed decrease respiratory infections and skin disorders among FET infants suggests a possible advantage in immune system development or environmental adaptability. Further research with longer-term tracking is warranted. Trial registration number KMUHIRB-E(I)-20210222

O-148 Does presence of endometriosis adversely affect oocyte morphology? Evaluation of a large number of oocytes obtained from endometriosis patients, 27204 oocytes

Abstract Study question Does presence of endometriosis adversely affect oocyte morphology? Evaluation of a large number of oocytes obtained from endometriosis patients, 27204 oocytes Summary answer In the presence of endometriosis, oocyte morphology is not impaired. The rate of reaching blastocyst and fertiilization rate, also pregnancy outcomes are not affected negatively. What is known already Although there are hypothesis, theories that altered steroidogenesis and folliculogenesis, higher oxidative stress, reactive oxygen species, altered cell cycle progression, inflammation and angiogenesis in the follicular environment exposes oocytes to a hostile inflammatory environment and alters oocyte quality. There has been much debate and conflicting evidence as to whether the poorer IVF outcomes in women with endometriosis is related to altered oocyte quality. There is some evidence to suggest that impaired oocyte morphology in women with endometriosis may have an adverse impact on fertilization rate, however, most studies have shown that there is no difference in pregnancy outcomes following IVF. Study design, size, duration This retrospective, single center study evaluated 29130 ART cycles from August 2011 to March 2023,based on data obtained from Istanbul Memorial Hospital,ART and Reproductive Genetics Center.Study group included endometriosis patients(n = 4602 cycles, 27204 oocytes) and control group included non-endometriosis patients(n = 24528 cycles, 178774 oocytes).We analyzed demographic and cycle characteristics, oocyte morphology in ART cycles between the two groups.Futhermore, we compared pregnancy outcomes in frozen-thawed embryo transfer(FET) cycles (total number:11116 FET cycles; endometriosis group:2255 cycles,non-endometriosis group:8861 cycles). Participants/materials, setting, methods Patients diagnosed with endometrioma by ultrasound, diagnosed with endometriosis by laparoscopy or patients who underwent endometrioma surgery or adenomyosis detected on ultrasound were included in the study (endometriosis) group. In the control group, the patients without endometriosis were included. Mann Whitney U test and Pearson Chi-square test used. Cliff's Delta effect size (????) for non-parametric tests and Phi effect size (p) for categorical data were reported. Main results and the role of chance The sample was very large, so the statistical results were given in terms of effect size, not only p value calculated. Female age was similar. Female body mass index, number of previous cycles, duration of infertility, AMH, total gonadotropin dosage used, duration of ovarian stimulation, estradiol level on trigger day, number of aspirated oocytes, mature and fertilized oocytes, maturation and fertilization rate, rate of blastulation, rate of usable blastocyst (top and good quality), number of embryos transferred, blastocyst stage embryo transfer cycles were statistically different between the two groups (p < 0.001). However when the effect size examined, all variables were found to have a negligible association by Cliff's Delta or Phi effect size calculations. Oocytes obtained from endometriosis patients had statistically significantly higher severe central granulation, large perivitellin space, thick zona, polar body defect abnormalities compared to non-endometriosis patients (p < 0.001), Phi effect size showed negligible association for all variables. In endometriosis group compared to non endometriosis group; biochemical pregnancy (68.9% vs 72.2%, p:0.002, Phi:0.030), clinical pregnancy (61.5% vs 64.5%, p:0.007, Phi:0.025), total pregnancy loss (22% vs 24.4%, p:0.05, Phi:0.022) were statistically higher, but Phi effect sizes were negligible. Live birth were similar (52.5% vs 53.2 P:0.56) between the two groups. Limitations, reasons for caution The principal limitation of the study is retrospective design of the analysis. But the strength of the study is that included 27204 oocytes from endometriosis patients. Wider implications of the findings To our knowledge, this study includes the largest case group that investigates the endometriosis and oocyte morphology. The results show that endometriosis does not have a negative impact on oocyte morphology. Additionally, it has been shown that the presence of endometriosis does not have a negative effect on pregnancy outcomes. Trial registration number *

P-781 Managing a change of provider bank in a vitrified oocyte donation program

Abstract Study question Does a change in provider bank affect the outcomes of a vitrified oocyte donation program and require laboratory and clinical adjustments? Summary answer In a vitrified oocyte donation program, a change in the provider bank does not affect patients’ outcomes nor require laboratory or clinical adjustments. What is known already Imported vitrified oocyte donation programs are a valuable strategy to provide oocyte donation treatments in settings were donor availability is low or absent. Little is known about how to a change in the provider oocyte bank should be managed in terms of laboratory or clinical adjustments in order not to jeopardize patients’ outcomes. Study design, size, duration Longitudinal cohort study conducted in a Tertiary IVF Center (Centro Scienze Natalità, IRCCS Ospedale San Raffaele, Milan, Italy) between September 2019 and October 2023. Participants/materials, setting, methods All couples undergoing their first imported vitrified oocyte donation cycle were included (n = 235). Oocytes (6 to 9 per cycle) were purchased from one bank (Bank A, Spain, EU) until December 2022 and then from a different bank (Bank B, Spain, EU) from January to October 2023. Single blastocyst-stage embryo transfer policy was adopted in all patients and the cumulative outcomes of patients treated with oocytes purchased from Bank A and Bank B were compared. Main results and the role of chance The number of provided oocytes was higher in Bank B compared to Bank A (8.0 ± 0.8 vs 6.5 ± 0.7, Mean ± SD, p < 0.01). Oocyte survival rates at thawing (87.2 ± 17.2 vs 91.2 ± 16.1 %, Mean ± SD), fertilization rates (75.7 ± 20.8 vs 78.4 ± 28.7, Mean ± SD) and blastulation rates (49.0 ± 28.0 vs 54.5 ± 27.5, Mean ± SD) were stable between Bank A and Bank B respectively, resulting in a higher number of blastocysts available for transfer in cycles performed with oocytes from Bank B compared to Bank A (3.5 ± 2.0 vs 2.4 ± 1.5, Mean ± SD, p < 0.01). Cumulative outcomes showed an improvement in cycles performed with Bank B compared to Bank A (implantation rates 73.8 % vs 62.6 %, ongoing pregnancy rates 69.8 % vs 56.3 %), despite not reaching a statistically significant difference. On multivariate logistic regression, the number of blastocysts available for transfer (OR 2.1, 1.7 -2.7 95% CI, p < 0.01) but not the Bank providing the vitrified oocytes (OR 0.99, 0.40 – 2.43) resulted as significant predictor of ongoing pregnancy. Limitations, reasons for caution Longer follow-up might strengthen our results, as several cycles performed with Bank B are still ongoing and cumulative live-birth rates cannot be currently calculated. In addition, the two banks used are located in the same country. Whether these results also apply to banks located in different settings needs further investigation. Wider implications of the findings Our results reassure about the possibility to manage a vitrified oocyte donation program using oocytes from different banks without jeopardizing patients’ outcomes and without the need for laboratory and clinical adjustments. Trial registration number not applicable

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

ObjectiveThis 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.MethodsThis 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).ResultsFollowing 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).ConclusionWith 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.

Competent blastocyst and receptivity endometrium improved clinical pregnancy in fresh embryo transfer cycles: a retrospective cohort study

BackgroundEmbryo quality is usually regarded as a key predictor of successful implantation and clinical pregnancy potential. The identification of embryos that have the capacity to implant and result in a healthy pregnancy is a crucial part of in vitro fertilization (IVF). Usually, morphologically high-quality embryos are chosen for embryo transfer in IVF treatment. The aim of this study was to assess the association between the available blastocyst formation rate and the clinical pregnancy outcome following the first fresh embryo transfer cycle and provide systematic individual treatment to adjust endometrial receptivity for the next transfer cycle.MethodsThis retrospective, single-center study included 512 fresh embryo transfers conducted between 11/2019 and 08/2021, which consisted of 385 cleavage-stage (Day 3) and 127 blastocyst-stage (Day 5) embryo transfers. The two groups were divided into a clinical pregnancy group and a nonclinical pregnancy group for comparison. The association between the available blastocyst formation rate and the clinical pregnancy rate in the Day 3 and Day 5 transfer groups were considered.ResultsIn the Day 3 group, there were 275 clinical pregnancies, and the clinical pregnancy rate was 71.43%. Although the two pronuclei (2PN) oocyte rate and available embryo rate at Day 3 were significantly higher in the clinical pregnancy group than the nonclinical pregnancy group (P < 0.05), the blastocyst formation rate and the available blastocyst formation rate were not significantly different between the clinical pregnancy group and the nonclinical pregnancy group (P > 0.05). In the Day 5 group, there were 81 clinical pregnancies, and the clinical pregnancy rate was 63.78%. No baseline characteristics showed any obvious differences between the clinical pregnancy group and nonclinical pregnancy group (P > 0.05). The blastocyst formation rate in the nonclinical pregnancy group was higher than that in the clinical pregnancy group, but the difference was not statistically significant (81.06% vs. 77.03%, P = 0.083). Interestingly, the available blastocyst formation rate and the Day 5 available blastocyst formation rate were significantly higher in the nonclinical pregnancy group than the clinical pregnancy group (66.19% vs. 60.79%, P = 0.014; 54.58% vs. 46.98%, P = 0.007).ConclusionsIn fresh cycles, the available blastocyst formation rate was not associated with the clinical pregnancy outcome for Day 3 embryo transfers, and the available blastocyst formation rate was not positively correlated with the clinical pregnancy outcome for Day 5 embryo transfers.

Single Blastocyst-Stage Embryo Transfer should be Promoted for IVF Cycles Using Donor Sperm (IVFD)

Single Blastocyst-Stage Embryo Transfer should be Promoted for IVF Cycles Using Donor Sperm (IVFD)

Effect of frozen-thawed embryo transfer with a poor-quality embryo and a good-quality embryo on pregnancy and neonatal outcomes.

To evaluate the impact of embryo quality and quantity, specifically a poor quality embryo (PQE) in combination with a good quality embryo (GQE), by double embryo transfer (DET) on the live birth rate (LBR) and neonatal outcomes in patients undergoing frozen-thawed embryo transfer (FET) cycles. A study on a cohort of women who underwent a total of 1462 frozen-thawed cleavage or blastocyst embryo transfer cycles with autologous oocytes was conducted between January 2018 and December 2021. To compare the outcomes between single embryo transfer (SET) with a GQE and DET with a GQE and a PQE, propensity score matching (PSM) was applied to control for potential confounders, and a generalized estimating equation (GEE) model was used to determine the association between the effect of an additional PQE and the outcomes. Subgroup analysis was also performed for patients stratified by female age. After PS matching, DET-GQE + PQE did not significantly alter the LBR (adjusted odds ratio [OR] 1.421, 95% CI 0.907-2.228) compared with SET-GQE in cleavage-stage embryo transfer but did increase the multiple birth rate (MBR, [OR] 3.917, 95% CI 1.189-12.911). However, in patients who underwent blastocyst-stage embryo transfer, adding a second PQE increased the live birth rate by 7.8% ([OR] 1.477, 95% CI 1.046-2.086) and the multiple birth rate by 19.6% ([OR] 28.355, 95% CI 3.926-204.790), and resulted in adverse neonatal outcomes. For patients who underwent cleavage-stage embryo transfer, transferring a PQE with a GQE led to a significant increase in the MBR ([OR] 4.724, 95% CI 1.121-19.913) in women under 35 years old but not in the LBR ([OR] 1.227, 95% CI 0.719-2.092). The increases in LBR and MBR for DET-GQE + PQE compared with SET-GQE in women older than 35 years were nonsignificant toward. For patients who underwent blastocyst-stage embryo transfer, DET-GQE + PQE had a greater LBR ([OR] 1.803, 95% CI 1.165-2.789), MBR ([OR] 24.185, 95% CI 3.285-178.062) and preterm birth rate (PBR, [OR] 4.092, 95% CI 1.153-14.518) than did SET-GQE in women under 35 years old, while no significant impact on the LBR ([OR] 1.053, 95% CI 0.589-1.884) or MBR (0% vs. 8.3%) was observed in women older than 35 years. The addition of a PQE has no significant benefit on the LBR but significantly increases the MBR in patients who underwent frozen-thawed cleavage-stage embryo transfer. However, for patients who underwent blastocyst-stage embryo transfer, DET-GQE + PQE resulted in an increase in both the LBR and MBR, which may lead to adverse neonatal outcomes. Thus, the benefits and risks of double blastocyst-stage embryo transfer should be balanced. In patients younger than 35 years, SET-GQE achieved satisfactory LBR either in cleavage-stage embryo transfer or blastocyst-stage embryo transfer, while DET-GQE + PQE resulted in a dramatically increased MBR. Considering the low LBR in women older than 35 years who underwent single cleavage-stage embryo transfer, selective single blastocyst-stage embryo transfer appears to be a more promising approach for reducing the risk of multiple live births and adverse neonatal outcomes.

Perinatal outcomes of frozen-thawed embryo transfer following blastocyst-stage embryo transfer compared to those of cleavage-stage embryo transfer: Analysis of 9,408 singleton newborns using propensity score analysis

Objective: Regarding frozen-thawed embryo transfer (FET), there is limited consensus on whether extending embryo culture from the cleavage stage to the blastocyst stage affects perinatal outcomes. This study aimed to compare perinatal outcomes of singletons between blastocyst-stage transfer (BT) and cleavage-stage transfer (CT) in FET. Methods: A total of 9,408 FET cycles that met the inclusion criteria were included in this retrospective cohort study between 2019 and 2022. Blastocyst-stage embryo transfers were performed in the BT group, and cleavage-stage embryo transfers were performed in the CT group. Multivariate logistic regression analyses were performed, as well as propensity score matching (PSM) to adjust for confounders. Results: After PSM, a higher risk of preterm birth (PTB) (OR 1.23, 95% CI 1.00–1.50, P=0.048) and being large for gestational age (LGA) (OR 1.16, 95% CI 1.00–1.35, P=0.050) was observed in the BT group compared to that in the CT group. After stratified PSM, in the subgroup under 35 years of age, only an increased risk of LGA was observed in the BT group compared to the CT group. Perinatal outcomes in the double-embryo transfer subgroup were similar to those in the unstratified group. However, in the subgroup beyond 35 years of age and the single-embryo transfer subgroup, perinatal outcomes were not statistically different between the BT and CT groups (P&gt;0.05). Conclusions: In FET, prolonged embryo culture to the blastocyst stage increased the risk of PTB and LGA in single fetuses. However, stratified analysis based on age and the number of transferred embryos yielded different results, necessitating further mechanistic studies.

Benefits of Blastocyst Transfer With at Least Three Good-Quality Cleavage-stage Embryos in Women of Advanced Maternal Age: A Retrospective Analysis

ObjectivesLimited studies on the benefits of blastocyst transfer in advanced maternal age (AMA) (≥40 years) have been reported. Our objective was to find whether blastocyst-stage embryo transfer improves pregnancy and live birth rates in women ≥40 years who have 3 or more good-quality cleavage-stage embryos. MethodsAll fresh in vitro fertilization-intracytoplasmic sperm injection cycles performed from January 2020 to December 2021 in AMA women that progressed to transfer were considered for analysis. We compared fresh and cumulative ongoing pregnancy rates in AMA women of those who had a cleavage-stage transfer, while meeting the criteria for extended culture (≥3 high-quality embryos, group 1), and those who underwent blastocyst transfer (group 2). Demographic parameters, stimulation, embryology, fresh and cumulative ongoing pregnancy rates, and clinical miscarriage rates were compared. ResultsDuring the study period, 255 cycles were analyzed including group 1 (n = 99) and group 2 (n = 156). Group 1 participants were older and had a greater number of embryos for transfer. Fresh and cumulative ongoing pregnancy rates per transfer were higher in group 2 compared to group 1 (23.4% vs. 13.1%, P = 0.04; 25.5% vs. 14.1%, P = 0.03), while overall miscarriage rates were higher in group 1 than group 2 (51.7% vs. 25%, P = 0.01). ConclusionsBlastocyst culture provides a benefit to AMA women who have at least 3 good-quality embryos on day 3 resulting in significantly higher fresh and cumulative ongoing pregnancy rates and lower miscarriage compared to cleavage-stage transfers.

Intrauterine instillation of human chorionic gonadotropin at the time of blastocyst transfer: Systematic review and meta-analysis

Intrauterine instillation (IU) of Human Chorionic Gonadotropin (hCG) before embryo transfer (ET) has been proposed to enhance implantation success rates. This is the first meta-analysis to evaluate the effect at the blastocyst-stage. A systematic literature search was performed using Medline, Embase, Cochrane Library and Google. Randomized clinical trials (RCTs) were included. The primary outcome combined live birth rate (LBR) and ongoing pregnancy rate (OPR). The secondary outcomes were clinical pregnancy rate (CPR), implantation rate (IR) and miscarriage rate (MR). 93 citations were identified, of which there were seven eligible RCTs. 2499 participants were included in the meta-analysis; 1331 were assigned to an experimental group and 1168 were assigned to the control group. The overall effect of IU hCG instillation on LBR and OPR was not significant: risk ratio (RR) 1.00 (95% CI, 0.90–1.12). Analysis of secondary outcomes found the effect of IU hCG instillation was not significant. Analysis of the data suggests that the studies conducted have too much heterogeneity to identify whether a specific cohort may have a significant benefit. The findings of this meta-analysis demonstrate that there is insufficient evidence at present to support the use of IU hCG instillation prior to blastocyst-stage ET.

Health assessment of Holstein calves born after in vitro fertilization, biopsy-based genotyping at the blastocyst stage and subsequent embryo transfer

Establishing methods for evaluating genomic estimated breeding values of bovine embryos can potentially increase the efficiency of breeding programs by transferring only embryos with a high genomic estimated breeding value. This may be achieved by analyzing DNA from trophectoderm biopsies. However, manipulation of bovine embryos is associated with a risk of impaired conceptus health. More knowledge on the health implications of embryonic handling procedures is required. In this study, we followed pregnancies after transfer of in vitro-produced (IVP) embryos and assessed the health of the offspring during the first 2 weeks of life. Three groups of calves were studied: i) freshly transferred non-biopsied embryos (39 transfers, 17 calves; Group B-/C-); ii) biopsied and freshly transferred IVP embryos (42 transfers, 21 calves; Group B+/C-); iii) biopsied and cryopreserved IVP embryos (17 transfers, 6 calves; Group B+/C+). Blood biochemical and hematologic values were compared between groups and to a control group of 13 calves produced by conventional artificial insemination. The pregnancy rate on day 50 and the calving rate did not differ among the groups, but the average gestation length of the B+/C+ group was significantly shorter and with wider variation than the two other groups. There was a tendency toward a higher average body weight at birth in group B+/C+ (45.1 kg) and the standard deviation in body weight was larger (11.7 kg) compared to the B-/C- (39.5 kg; 3.2 kg) and B+/C- (41.8 kg; 6 kg) groups. Body weight on day 14 was higher in the B+/C+ calves compared to the other groups. There was no difference in the biochemical and hematological values at birth between the groups and these were within the normal range. However, when compared to a group of calves produced by standard artificial insemination, significantly higher concentrations were found for the hepatic-related enzymes ALAT, ASAT, ALP, and GGT in group B-/C-and B+/C-, while only higher ALP concentrations were found in B+/C+ calves. The biochemical findings indicate higher heterogeneity in IVP calves compared to calves produced by artificial insemination. The more manipulated IVP embryos also showed increased heterogeneity in body weight at birth, with a shift toward heavier calves, which calls for closer attendance at parturition to handle dystocia in a timely manner and minimize fetal losses.

Sex-specific differences in head circumference of term singletons after assisted reproductive technology: a multicentre study in Japan

Research questionDoes fertility treatment, specifically assisted reproductive technology (ART), affect head circumference in term singletons? DesignA total of 32,651 women who delivered at term at 12 maternity hospitals in Japan between 2010 and 2018 were included in the analysis; of these, 1941 (5.9%) and 2984 (9.1%) women conceived through ART and non-ART fertility treatments (timed intercourse, ovulation induction or artificial insemination), respectively. The study evaluated the adjusted odds ratios of head circumference ≥90th percentile stratified by infant sex and type of ART procedure after adjusting for covariates, with natural conception as the reference group. ResultsART significantly increased the risk of head circumference ≥90th percentile (adjusted odds ratio 1.56 [95% confidence interval 1.25–1.96]), whereas non-ART fertility treatment did not increase the risk (1.14 [0.92–1.42]). This increased risk of head circumference ≥90th percentile was observed exclusively in male neonates (1.73 [1.33–2.26]) and not in female neonates (1.18 [0.76–1.85]) in the ART group. Frozen embryo transfer (FET), FET in a hormone replacement cycle (HRC-FET) and blastocyst-stage embryo transfer were significantly associated with head circumference ≥90th percentile (1.60 [1.26–2.02], 1.70 [1.30–2.22] and 1.72 [1.33–2.24], respectively). ConclusionsThe use of ART, particularly FET, HRC-FET or blastocyst-stage embryo transfer, was linked with a heightened risk of head circumference ≥90th percentile compared with non-ART fertility treatment or natural conception. The increased risk was observed only in male neonates.

Clinical outcome of different embryo transfer strategies after late rescue ICSI procedure: a 10-year total fertilisation failure cohort study

BackgroundLate rescue intracytoplasmic sperm injection (r-ICSI) has not been widely accepted as an alternative solution for unexpected total fertilisation failure (TFF) after in vitro fertilisation (IVF), due to the time-dependent in vitro deterioration of oocyte quality and endometrial growth not being synchronised with embryo development. This study aimed to evaluate the safety profile and effectiveness of freeze-all blastocyst transfer in combination with late r-ICSI.MethodsThis was a retrospective cohort study carried out at the Reproductive Centre of Peking University Third Hospital, Beijing, China. All participants received treatment between 2009 and 2019. 2,270 patients in the aggregate encountered unexpected TFF during 149,054 cycles of IVF and adopted a late r-ICSI procedure. Among these patients, 263 women did not have cleavage-stage embryos available for evaluation. The remaining patients were grouped according to different embryo transfer (ET) strategies (926 women in Group 1 underwent fresh ET, 365 women in Group 2 underwent freeze-all ET, 716 women in Group 3 experienced blastulation failure). Patients received different ET strategies after r-ICSI, with the main outcome measures included live birth rate (LBR), cumulative live birth rate (cLBR), and conservative cLBR.ResultsTFF occurred in 7.4% of all IVF cycles. Group 1 tended to be older at oocyte retrieval, with more infertile years, higher follicle-stimulating hormone (FSH) levels, higher gonadotropin consumption, and fewer oocytes retrieved. Group 2 exhibited considerably better LBRs following the first ET cycle (37.53% vs. 4.64%) and cLBRs (52.60% vs. 8.21%). After adjustment for covariates using binary logistic regression analyses, Group 2 still showed better obstetric performance in LBRs [OR:11.77, 95% CI (8.42–16.45)], cLBRs (OR:11.29, 95% CI (7.84–16.27)], and conservative cLBRs (OR:2.55, 95% CI (1.83–3.55)]. Additionally, the two groups showed similar miscarriage rates, whilst no new-borns with malformations or congenital diseases were reported.ConclusionsFreeze-all blastocyst stage ET serves as an optimal strategy to support late r-ICSI. However, for women with limited oocytes available for r-ICSI use, weighing the benefits against the costs of the procedure might be prudent before implementing in vitro blastulation.

P-239 Comparison of reproductive outcomes for cleavage- and blastocyst-stage frozen embryo transfer: A retrospective study

Abstract Study question Does blastocyst-stage (day 5-6) embryo transfer improve pregnancy and live birth rates per frozen transfer compared to cleavage-stage (day 2-3) embryo transfer? Summary answer Pregnancy rate is significantly higher following frozen blastocyst-stage embryo transfer, while live birth rate does not differ. What is known already The extended culture of cleavage-stage (day 2-3) embryos to blastocyst-stage (day 5-6) embryos has been largely adopted in recent years. In fact, blastocyst culture may allow a better selection of the embryo to be transferred based on its developmental history and morphological criteria, and result in a lower number of exceeded embryos to be frozen for storage. However, the literature comparing pregnancy and live birth rates for cleavage- and blastocyst-stage transfer remains contradictory, and the benefits of frozen blastocyst transfer is still under discussion. Study design, size, duration This retrospective study investigated couples having frozen embryo transfer at the cleavage (days 2 or 3) or the blastocyst-stage (days 5 or 6) at our clinic between 2014–2021. Results from more cycles were analyzed individually. We excluded cycles based on fresh embryo transfer, oocyte or sperm donation. Cycles were further sub-classified based on the type of treatment, as natural or stimulated, and the pregnancy and live birth rates were compared. Participants/materials, setting, methods Data was obtained from patient records at our fertility clinic and sorted by two authors. Variables included female age, treatment plan, the stage of the embryo transferred, and the report of pregnancy and live birth. Statistical analysis was conducted by using MedCalc Software, and Chi-squared test applied to compare the outcomes’ frequency based on the day of frozen embryo transfer. P &amp;lt; 0.05 was considered significant. Main results and the role of chance A total of 2,922 cycles were included for analysis, with age of female patients being 37.2 ± 5.0 years at the time of transfer. Most cycles were stimulated (n = 2,217, 75.9%) compared to natural cycles (n = 705, 24.1%). In all cycles, IVF was used for fertilization. Approximately one third of the cycles (n = 954, 32.6%) underwent frozen embryo transfer at the cleavage-stage (days 2 or 3), while the remaining had transfer at the blastocyst-stage (n = 1,968, 67.4%). Pregnancy rate was significantly (P &amp;lt; 0.0001) higher for blastocyst-stage embryo transfer compared to cleavage-stage embryo transfer (36.2% vs 20.4%, respectively) when all cycles were analyzed. This significance was found when natural (23.3% vs 14.8%, P = 0.0052) or stimulated cycles (38.0% vs 25.8%, P &amp;lt; 0.0001) were sub-analyzed. While we observed 19.0% of successful live birth per embryo transferred in the entire cohort, this did not significantly vary depending on the stage of frozen embryo transferred (cleavage or blastocyst-stage, 13.6% vs 21.5%, respectively) and when patients were sub-classified based on the type of treatment chosen in natural (9.0% vs 14.2% respectively) or stimulated (18.0% vs 22.6%, respectively) cycles. With a large sample size and a very significant P-value for pregnancy rate, the role of chance is limited. Limitations, reasons for caution As a retrospective study, the non-random allocation to treatment groups might hide selection bias and limit the statistical power of the data analysis, especially for the live birth rate. Also, no adjustment for confounders was performed. Wider implications of the findings Frozen embryo transfer at blastocyst-stage may offer an improved chance of pregnancy in both natural and stimulated cycles, possibly resulting in less embryos stored and lower costs for patient treatment. Although no difference was observed, larger prospective studies are needed to clarify the impact on live birth rate. Trial registration number Not applicable

O-005 The ToF-study - comparing the cumulative live birth rate of blastocyst-stage versus cleavage-stage embryo transfers in good prognosis IVF patients: a multicenter randomized controlled trial.

Abstract Study question Does blastocyst-stage embryo transfer in fresh and frozen cycles improve the cumulative live birth rate (cLBR) compared with cleavage-stage embryo transfer in IVF/ICSI treatments? Summary answer In good prognosis IVF patients (≥4 available embryos), a blastocyst-stage transfer policy did not result in a significant higher cLBR compared to cleavage-stage transfer policy. What is known already A recent Cochrane systematic review and meta-analysis concluded that fresh blastocyst-stage transfer in IVF/ICSI treatments is associated with higher rates of pregnancy in comparison to fresh transfer of cleavage-stage embryos. However, it is unknown whether a blastocyst-transfer policy also improves the cumulative live birth rate, i.e. the live birth rate derived from fresh and frozen-thawed embryo transfers following a single oocyte retrieval, in comparison to a cleavage-stage transfer policy in IVF/ICSI. Study design, size, duration In this multicenter randomized controlled trial women were randomly allocated to blastocyst-stage transfers (blastocyst group - fresh embryo transfer on day 5 after oocyte retrieval followed by vitrification of remnant blastocysts on day 5 and 6 following local criteria) or cleavage-stage transfers (cleavage-stage group - fresh embryo transfer on day 3 after oocyte retrieval followed by embryo cryopreservation on day 3 or 4). Randomization was stratified for age (≥36 or &amp;lt; 36 years). Participants/materials, setting, methods Women with a good prognosis after IVF/ICSI (defined as presenting ≥4 available embryos on day 2 of embryo culture), during their first, second, or third treatment cycle, were included. The primary outcome was the cLBR per oocyte retrieval, including associated frozen-thawed embryo transfers within 12 months after randomization (or 17 months during the COVID pandemic). Risk ratios (RR) with 95% CI adjusted for age group were calculated using log-linear binominal regression. Main results and the role of chance A total of 1202 women from 21 Dutch centers were randomly assigned to blastocyst-stage transfers (N = 599) or cleavage stage transfers (N = 603) between 2018 and 2021. At submission of this abstract, data on the primary outcome was available for 1153 (95.9%) women, 577 women in the blastocyst-stage group and 576 women in the cleavage-stage group. The cumulative live birth rate was 58.2% (336/577 women) in the blastocyst-stage group and 57.3% (330/576 women) in the cleavage stage group (RR 1.022, 95% CI 0.844-1.237; p = 0.825). The live birth rate after fresh embryo transfer was 38.0% (219/577 women) versus 29.9% (172/576 women) in the blastocyst-stage group and cleavage-stage group respectively (RR 1.282, 95% CI 1.017-1.615 p = 0.035). Interaction was found between age and day of transfer with a higher cumulative live birth rate and a higher live birth rate after fresh transfer in women of 36 years or older in the blastocyst group. Analyses on other IVF treatment outcomes, obstetrical or neonatal outcomes, patient burden, and cost effectiveness are ongoing. Limitations, reasons for caution Outcomes are only applicable for treatments of women with at least four embryos available on day two of embryo culture. Wider implications of the findings A blastocyst-stage embryo transfer policy did not result in a significant higher cumulative live birth rate in comparison to a cleavage-stage embryo transfer policy in IVF/ICSI treatments. Further research into the interaction of age with outcomes is warranted. Trial registration number NTR7034

P-153 Clinical outcome of different embryo transfer strategies after late rescue ICSI procedure: A cohort study based on over 140 thousand ART cycles

Abstract Study question How effective and safe is freeze-all blastocyst transfer in combination with late rescue intracytoplasmic sperm injection (r-ICSI)? Summary answer Freeze-all blastocyst stage embryo transfer (ET) serves as an optimal strategy to support late r-ICSI. What is known already Late r-ICSI has not been widely adopted due to the time-dependent in vitro deterioration of oocyte quality and endometrial growth not being synchronised with embryo development. Study design, size, duration This was a retrospective cohort study. All participants received treatment between 2009 and 2019. 2,270 patients in the aggregate encountered unexpected total fertilisation failure (TFF) during 149,054 cycles of in vitro fertilisation (IVF) and adopted a late r-ICSI procedure, whilst meeting the inclusion criteria for this study. Participants/materials, setting, methods Patients were grouped according to transfer strategies (926 women in Group 1 underwent fresh ET, 365 women in Group 2 underwent freeze-all ET, 716 women in Group 3 experienced blastulation failure, and 263 women did not have available D3 embryos). Patients received different ET strategies after r-ICSI, with the main outcome measures included live birth rate (LBR), cumulative live birth rate (cLBR), and conservative cLBR. Main results and the role of chance TFF occurred in 7.4 % of all IVF cycles. Group 1 tended to be older at oocyte retrieval [33.00 (30.00–37.00) vs. 31.00 (29.00–35.00), P &amp;lt; 0.001], with more infertile years [5.00 (3.00–8.00) vs. 3.00 (2.00–6.00), P &amp;lt; 0.001], higher follicle-stimulating hormone (FSH) levels [7.10 (5.71–8.69) vs. 6.61 (5.25–7.95) mIU/mL, P &amp;lt; 0.001], higher gonadotropin consumption [2850.00 (1950.00–4125.00) vs. 2325.00 (1800.00–3150.00) IU, P &amp;lt; 0.001], and fewer oocytes retrieved [10.00 (6.00–15.00) vs. 13.00 (9.00–19.00), P &amp;lt; 0.001]. Group 2 exhibited considerably better LBRs following the first ET cycle (37.53 % vs. 4.64 %) and cLBR (52.60 % vs. 8.21 %). After adjustment for covariates using binary logistic regression analyses, Group 2 still showed better obstetric performance in LBR (OR:11.77, 95 % CI (8.42–16.45)], cLBR (OR:11.29, 95 % CI (7.84–16.27)], and conservative cLBR (OR:2.55, 95 % CI (1.83–3.55)]. Additionally, the two groups showed similar miscarriage rates, whilst no new-borns with malformations or congenital diseases were reported. Limitations, reasons for caution This study was based on a retrospective cohort, which is inevitably associated with a skewed data distribution and inherent biases. Wider implications of the findings Our study highlights r-ICSI as a safe and effective alternate solution for unexpected TFF to aid frustrated couples. However, for women with limited oocytes available for r-ICSI use, weighing the benefits against the costs of the procedure might be prudent before implementing in vitro blastulation. Trial registration number NA

Perinatal outcomes in singleton live births after blastocyst transfer: an analysis of 60,926 in vitro fertilization cycles from the United Kingdom

To compare perinatal outcomes between singleton live births after blastocyst-stage and cleavage-stage fresh embryo transfer using data from all United Kingdom licensed fertility clinics. A cohort study. Not applicable. A total of 60,926 in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles resulting in a singleton live birth after blastocyst-stage and cleavage-stage fresh embryo transfer between 2012 and2018. Baseline characteristics between IVF/ICSI blastocyst and cleavage-stage transfer groups were compared using the χ2 test for categorical/dichotomized variables and the Mann-Whitney test for continuous variables. Statistical significance was set at <.05. Association between perinatal outcomes and blastocyst transfer compared with cleavage-stage transfer was assessed using multinomial logistic regression, adjusting for confounders selected using directed acyclic graphs (95% confidence interval [CI], adjusted relative risk ratio [aRRR]). A subgroup analysis included cycles in women undergoing their first IVF/ICSI cycle. Gestational age at birth and birth weight. The blastocyst group comprised 42,677 IVF/ICSI cycles and cleavage-stage group 18,249 cycles. There was likely little to no difference in the risk of preterm (aRRR, 1.07; 95% CI, 1.00-1.15) and very preterm birth (aRRR, 1.05; 95% CI, 0.91-1.21) in singleton live births after fresh blastocyst and cleavage-stage transfer. Risks of low birth weight (aRRR, 1.02; 95% CI, 0.95-1.09), very low birth weight (aRRR 0.96; 95% CI, 0.83-1.11), high birth weight (aRRR, 0.97; 95% CI, 0.90-1.04), and very high birth weight (aRRR, 0.91; 95% CI, 0.77-1.08) were likely similar between the groups. The findings were consistent in the subgroup analysis. Fresh blastocyst transfer does not appear to have a negative impact on gestational age at birth and birth weight in singleton live births compared with fresh cleavage-stage transfer.

Leukocyte Telomere Length in Children Born Following Blastocyst-Stage Embryo Transfer

ABSTRACT Several recent studies have suggested an association between children conceived by assisted reproductive technology (ART) and a distinct growth pattern in early life, which has been linked to diseases of older age. Telomere shortening, specifically a shorter leukocyte telomere length (LTL), has also been linked to age-related diseases including cardiometabolic diseases and cancer. Initial telomere length is shaped by a telomere reset process during gamete fertilization and the early stages of preimplantation development. Given that ART involves the in vitro manipulation of oocytes and embryos, this study aimed to evaluate the association between ART-related factors and LTL in children. Whole genome-sequencing (WGS) data from the Nanjing and Suzhou centers of the China National Birth Cohort (CNBC) were obtained from 1137 individuals from 365 parent-children families, including 202 children conceived using ART and 205 conceived spontaneously. The association was determined between blastocyst-stage transfer and shorter telomere length in 180 children conceived by ART in the same centers. In addition, qPCR was used to perform validation on fingerstick blood samples from 406 children conceived using ART at 3 different centers in China. Data from qPCR were then compared with data obtained from WGS in 70 children in the discovery cohort with sufficient DNA samples. Associations between parental factors and demographics with LTL were examined in the discovery cohort. LTL attribution with aging was calculated using data from the discovery cohort, 1185 individuals aged 40–69 years from healthy controls in the Nanjing Lung Cancer Cohort with LTL measured using WGS, and 1452 East Asian adults aged 40–69 years in the UK biobank with LTL measured using qPCR. Results of association analyses found paternal LTL (β = 0.27, P = 3.26 × 10−8), maternal LTL (β = 0.26, P = 2.41 × 10−7), plurality (twins vs singletons; β = −0.34, P = 0.010), sex of children (male vs female; β = −0.22, P = 0.032), gestational age (β = 0.05, P = 0.026), and conception type (ART-conceived pregnancy vs spontaneously conceived, β = −0.35, P = 5.98 × 10−4) were all significantly associated with LTL in children. Multivariate regression analysis revealed that children conceived by ART had a significantly shorter LTL than those conceived spontaneously, even when adjusting for parental age at conception (adjusted β = −0.41, P = 3.33 × 10−4). Transfer of blastocyst-stage embryos was found to be significantly associated with shorter LTL (β = −0.54, P = 2.69 × 10−3). In addition, when LTL in children from spontaneous pregnancies was compared with LTL in children from ART pregnancies through cleavage-stage versus blastocyst-stage transfer, the LTL of the cleavage-stage group was comparable to the spontaneous pregnancy group, whereas the LTL of the blastocyst-stage group was shorter (β = −0.67, P = 7.81 × 10−8). This result suggests that the difference in LTL between transfer stages might explain the difference between the ART-conceived and spontaneous pregnancy groups. No associations between COS protocols, fertilization methods, or embryo transfer cycles on shorter LTL in children were observed. The multicenter validation cohort had similar associations between blastocyst-stage transfer and shorter LTL. Shortened LTL associated with blastocyst transfer was equivalent to 13.93 years (95% CI, 4.64–23.22 years), 13.42 years (95% CI, 4.52–22.21 years), and 10.85 years (95% CI, 1.03–20.67 years) of aging between 40–69 years in the discovery and 2 validation cohorts, respectively. The results of this study demonstrate that children conceived by ART are associated with a shorter LTL compared with those conceived spontaneously, and transfer of blastocyst-stage embryos was associated with shorter LTL in children than is the transfer of cleavage-stage embryos.

A comparison of perinatal outcomes following fresh blastocyst or cleavage stage embryo transfer in singletons and twins and between singleton siblings.

Are perinatal outcomes following fresh blastocyst versus fresh cleavage stage embryo transfer (ET) different in singletons, twins, and between singleton siblings? Singleton babies conceived following fresh blastocyst, versus cleavage stage, ET are less likely to be small for gestational age (SGA) or to have a congenital anomaly (a result confirmed by comparing singleton siblings), while singletons born following fresh blastocyst ET were at a higher risk of being large for gestational age (LGA) than their sibling born following fresh cleavage stage ET. Blastocyst stage transfer is now the preferred strategy in most IVF units. Previous studies have suggested that babies conceived through blastocyst transfer are at increased risk of preterm birth and LGA. A national population-based retrospective cohort study was performed using linked Human Fertilisation and Embryology Authority (HFEA) data on 130 516 IVF and ICSI livebirths occurring from 103 062 women between 2000 and 2017. We included women who had at least one singleton livebirth resulting from IVF/ICSI fresh embryo treatment, using their own eggs and partner's sperm. A linked HFEA dataset was analysed using a multilevel framework, which accommodated repeated IVF cycles resulting in livebirths in the same woman. A population-averaged robust Poisson model was used for binary outcomes and a multinomial logistic regression model was used for categorical outcomes. Unadjusted and adjusted risk ratios (aRRs) (95% CI) were calculated. There were 130 516 livebirths in 103 062 women, including 86 630 singletons, 43 886 twin births, and 5384 pairs of singleton siblings. In comparison with fresh cleavage stage ET, fresh blastocyst stage transfer in singletons was associated with a lower risk of low birthweight (aRR = 0.92; 95% CI 0.86, 0.99), lower risk of being SGA (0.83; 0.78, 0.89), and lower risk of congenital anomaly (0.79; 0.71, 0.89). This analysis did not show an increase in risk associated with preterm birth (1.00; 0.94, 1.06), high birthweight (0.99; 0.93, 1.06), LGA (0.99; 0.93, 1.05), and the chance of healthy singleton baby (1.00; 1.00, 1.02). Twins resulting from fresh blastocyst stage ET were at slightly higher risk of preterm birth (1.05; 1.02, 1.10) compared with twins conceived following fresh cleavage stage ET. There was insufficient evidence for an association with the other perinatal outcomes. Singleton siblings born following fresh blastocyst stage ET were at a higher risk of being LGA (1.57; 1.01, 2.46) and at lower risk of having a congenital anomaly (0.52; 0.28, 0.97) compared to their singleton siblings born following cleavage stage ET. There was some evidence of excess risk of preterm birth (1.42; 0.97, 2.23) associated with blastocyst stage transfer. However, we could not confirm an association between blastocyst stage ET and low birthweight (1.35; 0.81, 2.27), high birthweight (1.19; 0.80, 1.77), and the chance of being a healthy baby (0.97; 0.86, 1.09). This was an observational study where we were unable to adjust for some key confounders, such as maternal smoking status and BMI, which may change from one pregnancy to another and are not recorded in the HFEA dataset. In the largest study of its kind, our analysis of singleton siblings, corrected for unmeasured, non-time varying maternal factors, confirms the previously reported association between blastocyst transfer and LGA babies, and shows a reduced risk of congenital anomaly following blastocyst transfer. Our sibling analysis did not confirm a decreased risk of low birthweight following blastocyst transfer. Overall, absolute risks are low and there is insufficient evidence to challenge the practice of extended culture of embryos. This project is financed by an NHS Grampian Endowment Research Grant, project number 17/052. One of the authors, S.B., was the Editor in Chief of HROpen until 31 December 2022 and would have been in that role when the paper was first submitted. As an invited speaker, S.B. has received travel expenses, accommodation and honoraria from Merck, Organon, and Ferring. A.M. has received travel expenses, accommodation, and honoraria from Merck Serono, Cook Medical, Pharmasure, Gedeon Richter, and Ferring. D.J.M. is currently a HROpen Associate Editor. N/A.