Comparison of clinical outcome between day 5 and day 6 single blastocyst transfers in cycles undergoing preimplantation genetic testing for aneuploidy

ObjectiveIn vitro fertilization (IVF) treatment has gradually adopted the practice of culturing embryos until the blastocyst stage on the D5 or D6 as the standard approach. PGT-A is commonly used in vitro fertilization (IVF). This study aimed to evaluate the clinical outcomes of frozen embryo transfers (FETs) using single blastocyst transfers (SBTs) on the fifth (D5) or sixth (D6) day of development in cycles that underwent preimplantation genetic testing for aneuploidy (PGT-A).Materials and methodsThe patients who had at least one euploid or mosaic blastocyst of good quality determined by PGT-A results and received single embryo transfer (SET) cycles were included in the study. In this study, the live birth rate (LBR) and neonatal outcomes were compared after the transfer of single biopsied D5 and D6 blastocysts in frozen embryo transfer (FET) cycles.ResultsA total of 527 frozen-thawed blastocyst transfer (FET) cycles (8449 biopsied embryos were analyzed). No significant difference in the implantation rate (IR), clinical pregnancy rate (CPR), and live birth rate (LBR) between the transfers of D5 and D6 blastocysts. Birth weight was the only perinatal outcome that showed a significant difference between the D5 and D6 groups.ConclusionThe study confirmed that the transfer of a single euploid or mosaic blastocyst, regardless of whether it was on the fifth (D5) or sixth (D6) day of development, can lead to promising clinical results.     

Development and clinical application of a preimplantation genetic testing for monogenic disease (PGT-M) for beta thalassemia in Vietnam

PurposeThe purpose of this research is to study the clinical outcomes using a next-generation sequencing-based protocol allowing for simultaneous testing of mutations in the beta thalassemia (HBB) gene, including single nucleotide polymorphism (SNP) markers for PGT-M along with low-pass whole genome analysis of chromosome aneuploidies for PGT-A.MethodsA combined PGT-M (thalassemia) plus PGT-A system was developed for patients undergoing IVF in Vietnam. Here we developed a system for testing numerous thalassemia mutations plus SNP-based testing for backup mutation analysis and contamination control using next-generation sequencing (NGS). Low -pass next-generation sequencing was used to assess aneuploidy in some of the clinical PGT cases. Patients underwent IVF followed by embryo biopsy at the blastocyst stage for combined PGT-A/M.ResultsTwo cases have completed the entire process including transfer of embryos, while a further nine cases have completed the IVF and PGT-M/A analysis but have not completed embryo transfer. In the two cases with embryo transfer, both patients achieved pregnancy with an unaffected, euploid embryo confirmed through prenatal diagnosis. In the further nine cases, 39 embryos were biopsied and all passed QC for amplification. There were 8 unaffected embryos, 31 carrier embryos, and 11 affected embryos. A subset of 24 embryos also had PGT-A analysis with 22 euploid embryos and 2 aneuploid embryos.ConclusionsHere we report the development and clinical application of a combined PGT-M for HBB and PGT-A for gross chromosome aneuploidies from 11 patients with detailed laboratory findings along with 2 cases that have completed embryo transfer.     

植入前遗传学诊断/筛查技术指征进展

植入前遗传学诊断/筛查(PGD/PGS)技术发展多年,其指征始终存在争议。PGD指征较为明确,单基因遗传病、染色体异常人群、人类白细胞抗原(HLA)配型为其适用人群。PGS的指征争议较多,主要面向反复流产、反复植入失败、高龄人群,目的是提高妊娠率及活产率。然而第一代PGS技术[PGS#1,卵裂球活检及荧光原位杂交(FISH)-PGS]技术未显示明显效果,甚至降低了妊娠率及活产率。第二代PGS技术(PGS2.0)增加了严重男性因素不育为指征,其核心为囊胚活检及全染色体筛查(CCS),对上述人群的临床效果较为明显,降低了流产风险并提高了成功率及活产率。PGS2.0已极大地改变了辅助生殖技术(ART)面貌,可能成为未来生殖中心对所有患者的一个常规项目。目前仍然需要多中心前瞻性随机病例对照研究重新评估PGS。     

First report of a successful pregnancy by preimplantation genetic testing for Beckwith-Wiedemann syndrome

ObjectiveBeckwith-Wiedemann syndrome (BWS) is a rare imprinting gene disorder. Maternal CDKN1C mutation comprises 5% of etiologies of BWS. There is no successful report of preventing BWS by preimplantation genetic testing for monogenic disease (PGT-M) in the literature. Is PGT-M applicable for preventing BWS ?Case reportThis 39-year-old woman conceived naturally and delivered a boy who was diagnosed of BWS. The genetic testing of her son revealed CDKN1C gene mutation, and of the mother showed a carrier of the same mutation. She underwent controlled ovarian stimulation, oocyte pickup, and intracytoplasmic sperm injection. Trophectoderm biopsies were performed and samples were checked for PGT. Two wild-type and euploid embryos were thawed and transferred. One intrauterine pregnancy was achieved. The patient delivered a healthy female baby at 37 weeks of gestation.ConclusionIn this case, we first report a successful pregnancy with a wild-type CDKN1C gene baby achieved by PGT-M.     

Birth of a healthy child after preimplantation genetic screening of embryos from sperm of a man with non-mosaic Down syndrome

Purpose

The purpose of this study is to present a case of healthy infant born after intracytoplasmic sperm injection-in vitro fertilization (ICSI-IVF) with preimplantation genetic screening (PGS) using sperm from a man with non-mosaic trisomy 21 and a literature review.

Materials and methods

A 26-year-old euploid female and 29-year-old male with non-mosaic trisomy 21 and male factor undergoing ICSI-IVF treatment for primary infertility with embryo biopsy for PGS with comprehensive chromosomal screening (CCS) presented to the Infertility Clinic at Highland Hospital, the Alameda County Medical Center, California, with 6-year history of primary infertility. The outcome measure is a live birth of a healthy child and ploidy status of biopsied blastocysts.

Results

Egg retrieval yielded 33 oocytes, 29 of which underwent ICSI with ejaculated sperm. Twenty-eight 2PN zygotes were cultured, and 13 blastocysts underwent trophectoderm biopsy and vitrification 5 or 6 days after retrieval. CCS analysis revealed that 12 out of 13 (92 %) of blastocysts were euploid and one was a complex abnormal mosaic. Transfer of two grade I hatching blastocysts resulted in a singleton pregnancy with normal prenatal genetic screening and delivery of a healthy male infant at 41 weeks via primary cesarean section for non-reassuring fetal status.

Conclusion

This is the first report of a live birth of a healthy child after ICSI-IVF with PGS using ejaculated sperm from a man with non-mosaic trisomy 21 and male factor infertility.     

Linking back-to-back stimulation cycles with oral contraceptives or progestins in women undergoing embryo accumulation for preimplantation genetic testing,a retrospective study

Abstract

The purpose of this study was to determine the pregnancy rate in the double sequential transfer of embryos on both day 3 and day 5 compared to day 5 alone, in in vitro fertilization-embryo transfer (IVF/ET) in patients with the three repeated consecutive IVF failures. In this controlled trial, women scheduled for IVF/ET with the three repeated consecutive IVF failures were randomized to either sequential transfer of embryos on day 2 and on day 5 after ovum pick-up (group 1, n = 60) or blastocyst ET on day 5 (group 2, n = 60) as a control group. The primary outcome measures were the chemical and clinical pregnancy rate. Baseline and cycle characteristics were comparable in both groups. Chemical and clinical pregnancy rate was similar in the sequential ET group (40%) compared to the day 5 of ET group (38.3%) (p value = .85). It seems that the double ET does not increase the chance of pregnancy rate compared to blastocyst ET on day 5 in the patients with the three repeated IVF-ET failures.     

Embryo morphokinetics is potentially associated with clinical outcomes of single-embryo transfers in preimplantation genetic testing for aneuploidy cycles

Research questionAre the morphokinetics of euploid blastocysts evaluated by a generally applicable algorithm associated with the clinical outcomes of single-embryo transfer (SET)?DesignTime-lapse microscopy was used to compare morphokinetic variables between expanded blastocysts derived from preimplantation genetic testing for aneuploidy cycles using high-resolution next-generation sequencing (hr-NGS). The clinical efficacy of the morphokinetic algorithm KIDScore D5 was evaluated after euploid SET.ResultsCompared with euploid blastocysts, low-level mosaic blastocysts presented comparable morphokinetic and morphological features. However, high-level mosaic blastocysts exhibited significant delays in t5 (median 51.9 h post insemination (hpi), P = 0.034) (where t is the time for the embryo to reach the specific stage in hours after ICSI or conventional IVF) and t8 (median 58.6 hpi, P = 0.032) accompanied by a prolonged time period for the third cell cycle (median 14.7 h, P = 0.012). A significantly higher incidence (P = 0.011) of multinucleation indicated a susceptibility of high-level mosaic blastocysts to mitotic errors. Only a delay in the time for the embryo to reach the full blastocyst stage (median 106.0 hpi, P = 0.039) was revealed in aneuploid blastocysts, reflecting the reduced formation of good-quality blastocysts (42.6% versus 65.7%, P < 0.001). Euploid blastocysts with specific morphokinetic characteristics were graded using the KIDScore D5 algorithm. Grade C embryos achieved significantly lower rates of clinical pregnancy, implantation and ongoing pregnancy (25%, 25% and 10%, respectively) compared with the grade A (76.2%, 79.4% and 68.3%, respectively) or grade B (62.5%, 66.7% and 62.5%, respectively) embryos (P = 0.0171 to <0.0001).ConclusionsAlthough morphokinetic features appear dissimilar in embryos with different diploid–aneuploid mosaic levels, predicting chromosomal abnormalities using morphokinetics alone is still insufficient. When combined with hr-NGS, use of the generally applicable KIDScore D5 algorithm has the potential to discriminate euploid blastocysts with different developmental competence.     

Laser-assisted hatching improves pregnancy outcomes in frozen-thawed embryo transfer cycles of cleavage-stage embryos: a large retrospective cohort study with propensity score matching

IntroductionLaser-assisted hatching (LAH) is a commonly used adjunct technique; however, its effectiveness has not been fully established.ObjectiveWe evaluated the effects of LAH on pregnancy outcomes in frozen-thawed embryo transfer (FET) cycles of cleavage-stage embryos.Materials and methodsThis retrospective study involved 5779 FET cycles performed at the Reproductive and Genetic Center in the Affiliated Hospital of Shandong University of Traditional Chinese Medicine between January 2016 and December 2020. After propensity score matching, 3535 FET cycles were included, out of which 1238 were subjected to LAH while the remaining 2297 cycles were non-LAH (NLAH). The primary outcomes were clinical pregnancy rate (CPR) and live birth rate (LBR) while secondary outcomes included implantation rate (IR), biochemical pregnancy rate (BPR), ectopic pregnancy rate (EPR), pregnancy loss rate (PLR), multiple pregnancy rate (MPL), and monozygotic twinning rate (MTR). Logistic regression analysis was conducted to adjust for possible confounders. Subgroup analysis was also performed based on the endometrial preparation regimen.ResultsThe LAH group exhibited a higher LBR, compared to the NLAH group (34.9% vs. 31.4%, OR = 1.185, 95% CI = 1.023, 1.374, P = 0.024). Additionally, the LAH group showed a decreasing trend in PLR and EPR; however, differences were insignificant (P = 0.078, P = 0.063 respectively). Differences in IR (24.6% vs. 24.3%), BPR (41.8% vs. 40.4%), CPR (40.7% vs. 38.3%), MPR (14.1% vs. 17.3%), and MTR (1.4% vs. 1.1%) were insignificant. Subgroup analysis revealed that LAH may be more conducive for pregnancy outcomes in hormone replacement cycles.ConclusionsIn summary, LAH has an increased chance of achieving live births. However, further prospective studies should be performed to confirm our findings.     

The effect of preimplantation genetic screening on the probability of live birth in young women with recurrent implantation failure; a nonrandomized parallel group trial

Objective

The aim of this study was to evaluate the efficacy of preimplantation genetic screening (PGS) in women younger than 38 years and who had recurrent implantation failure (RIF).

Study design

A prospective nonrandomized parallel group study was performed in the assisted reproduction unit of a private tertiary care hospital. 140 infertile couples who had three or more previous failed cycles were included. Genetic counseling was given and couples who opted for another treatment cycle with PGS (n = 54) formed the PGS group whereas couples who declined PGS formed the control group (n = 86). In the PGS group, following FISH analysis for the detection of chromosomes 13, 16, 18, 21, 22, X and Y, only euploid embryos were transferred on day 5. In the control group embryo transfer was performed on day 3. Clinical pregnancy and live birth rates were compared. 95% confidence intervals for differences between the groups were calculated.

Results

Baseline and treatment cycle characteristics were similar in both groups. In the PGS group, a mean number of two embryos were transferred; there were 8 clinical pregnancies (14.8%). The implantation rate was 11.9%. There were no miscarriages and the live birth rate was 14.8%. In the control group, a mean number of 2.7 embryos were transferred resulting in 23 pregnancies (26.7%). The implantation rate was 18.4%. There were 2 miscarriages and the live birth rate was 24.4%. The differences among the groups were not statistically significant.

Conclusion

The results suggest that this particular group of young patients with RIF may not benefit from PGS. However, PGS is a multistep procedure that is highly human dependent, and results may vary across laboratories.     

Trophectoderm biopsy protocols may impact the rate of mosaic blastocysts in cycles with pre-implantation genetic testing for aneuploidy

PurposeThis study aimed to analyze the impact of different biopsy protocols on the rate of mosaic blastocysts.MethodsThis is a retrospective cohort study which included 115 cycles with pre-implantation genetic testing for aneuploidy (PGT-A). Two groups were allocated based on the biopsy protocols: method 1 group, the zona pellucida (ZP) was drilled on day 3 embryos followed by trophectoderm (TE) biopsy; and method 2 group, the ZP was opened on day 5 or 6 blastocysts followed by TE biopsy. All biopsy samples were assessed using next-generation sequencing (NGS) at a single reference laboratory. The euploid, aneuploid, and mosaic blastocyst rates and clinical outcomes were compared.ResultsThe mosaicism rate in the method 1 group was 19.58%, significantly higher than the method 2 group (8.12%; P < 0.05). No statistically significant difference was observed in euploid, aneuploid blastocyst rates, and clinical pregnancy rates between the two groups. Logistic regression analysis indicated that the biopsy protocols were independently associated with the mosaicism rates among all the variables.ConclusionsThe present study showed that different biopsy protocols may have an impact on the mosaic blastocyst rate. ZP opening on day 3 combined with TE biopsy might increase the incidence of mosaic blastocysts.     

IVF/ICSI with or without preimplantation genetic screening for aneuploidy in couples without genetic disorders: a systematic review and meta-analysis

Purpose  To assess the efficacy of preimplantation genetic screening to increase ongoing pregnancy rates in couples without known genetic disorders. Methods  Systematic review and meta-analysis of randomized controlled trials. Two reviewers independently determined study eligibility and extracted data. Results  Ten randomized trials (1,512 women) were included. The quality of evidence was moderate. Meta-analyses using a random-effects model suggest that PGS has a lower rate of ongoing pregnancies (risk ratio=0.73, 95% confidence interval 0.62–0.87) and a lower rate of live births (risk ratio=0.76, 95% confidence interval 0.64–0.91) than standard in vitro fertilization/intracytoplasmic sperm injection. Conclusions  In women with poor prognosis or in general in vitro fertilization program, in vitro fertilization/intracytoplasmic sperm injection with preimplantation genetic screening for aneuploidy does not increase but instead was associated with lower rates of ongoing pregnancies and live births. The use of preimplantation genetic screening in daily practice does not appear to be justified. Capsule   Preimplantation genetic screening does not increase pregnancy rates in advanced maternal age, recurrent implantation failure, repeated miscarriages, or in general IVF population.     

An overview of the current and emerging platforms for preimplantation genetic testing for aneuploidies (PGT-A) in in vitro fertilization programs

Preimplantation genetic testing for aneuploidies (PGT-A) and PGT for monogenic disorders (PGT-M) have currently been used widely, aiming to improve IVF outcomes. Although with many years of unsatisfactory results, PGT-A has been revived because new technologies have been adopted, such as platforms to examine all 24 types of chromosomes in blastocysts. This report compiles current knowledge regarding the available PGT platforms, including quantitative PCR, array CGH, and next-generation sequencing. The diagnostic capabilities of are compared and respective advantages/disadvantages outlined. We also address the limitations of current technologies, such as assignment of embryos with balanced translocation. We also discuss the emerging novel PGT technologies that likely will change our future practice, such as non-invasive PGT examining spent culture medium. Current literature suggest that most platforms can effectively reach concordant results regarding whole-chromosome ploidy status of all 24 types of chromosomes. However, different platforms have different resolutions and experimental complexities; leading to different turnaround time, throughput and differential capabilities of detecting mosaicism, segmental mutations, unbalanced translocations, concurrent PGT-A and PGT-M etc. Based on these information, IVF staff can more appropriately interpret PGT data and counsel patients, and select suitable platforms to meet personalized needs. The present report also concisely discusses some crucial clinical outcomes by PGT, which can clarify the role of applying PGT in daily IVF programs. Finally the up-to-date information about the novel use of current technologies and the newly emerging technologies will also help identify the focus areas for the design of new platforms for PGT in the future.     

Evaluation of chromosomal abnormalities from preimplantation genetic testing to the reproductive outcomes: a comparison between three different structural rearrangements based on next-generation sequencing

PurposeThe aim of this study was to determine factors affecting the chromosome imbalance in blastocysts and reproductive outcomes by a comparison between the reciprocal translocation (REC), inversion (INV), and Robertsonian translocation (ROB) carriers.MethodsCouples with one partner carrying translocation or inversion underwent preimplantation genetic testing for chromosomal structural rearrangement (PGT-SR) cycles, including 215 PGT-SR cycles performed in subsequent 164 frozen-thawed embryo transfer cycles and 61 prenatal diagnoses of fetuses and 59 normal live birth babies. A total of 899 samples were processed by whole-genome amplification followed by next-generation sequencing (NGS). Karyotype and chromosome microarray analyses were used to confirm the PGT results from the amniotic fluid samples.ResultsA total of 843 blastocysts from 124 REC, 21 INV, and 35 ROB carriers were diagnosed by PGT-SR. The percentage of unbalanced blastocysts was significantly higher in REC than in INV and ROB carriers (64.31% vs. 28.05% vs. 37.02%). Stratification analysis of female carrier age and gonadotropin doses showed no significant increase in unbalanced chromosomal abnormalities in the three groups. Also, the different breakpoints in chromosomal arms did not affect the rate of unbalanced chromosomes in the embryos. Logistic regression indicated blastocyst quality as a statistically significant risk factor associated with unbalanced chromosomal abnormalities from translocation carriers (P < 0.001). The source of abnormalities in the three groups showed significant differences such that the abnormalities in REC mostly originated from parental translocation but the abnormalities in INV were mainly de novo variations. 164 blastocysts were transferred, and there were no significant differences in the clinical pregnancy rate and miscarriage rate. A total of 59 healthy babies were born, and there were no significant differences in the gender ratio and birth height, except the birth weight of boys between INV and ROB groups (P = 0.02). The results of amniocentesis revealed that more fetuses have normal chromosomal karyotypes than balanced carriers, particularly in the REC group.ConclusionsReciprocal translocation carriers have more risk of unbalanced rearrangement, but embryonic chromosome abnormalities of inversion carriers come mainly from de novo variations. This is the first study specifically comparing three different PGT-SRs using the NGS method and evaluating their reproductive outcomes. Our findings will provide the reciprocal translocation, inversion, and Robertsonian translocation carrier couples with more accurate genetic counseling on the reproductive risk of chromosomal imbalance.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10815-020-02053-5.     

Quality of embryos transferred and progesterone levels are the most important predictors of live birth after fresh embryo transfer: a retrospective cohort study

Purpose

To identify the independent predictors of live birth following IVF, and to assess the role of cohort-specific parameters, including antral follicle count (AFC), the number of oocytes retrieved, the total number of embryos, and the total number of good-quality embryos, in fresh IVF cycles.

Methods

A retrospective cohort study of 2,525 infertile women undergoing IVF between 2002 and 2007. The hypothesis that the number and quality of embryos transferred capture the effects previously attributed to cohort-specific variables was examined using mediation analysis and spline analysis. Independent predictors were identified by a bootstrap algorithm. Multivariable logistic regression was performed and the proportion of explained variation was measured to compare the relative importance of transfer-specific vs. cohort-specific predictors.

Results

The number of good-quality embryos transferred and progesterone level on the day of hCG administration ranked as the two most important predictors of live birth. Prospects of pregnancy started to decrease after progesterone level exceeded 0.6 ng/ml. The achievement of live birth in a fresh IVF cycle is primarily determined by the number and quality of embryos transferred, rather than by embryo cohort-specific variables.

Conclusions

The associations between cohort-specific variables and live birth in a fresh IVF cycle are completely mediated by the quality of embryos transferred. Progesterone level on the day of hCG administration is an independent predictor of pregnancy and merits further investigation.     

A greater number of euploid blastocysts in a given cohort predicts excellent outcomes in single embryo transfer cycles

Purpose

This multicentered retrospective study analyzed whether the quantity of euploid blastocysts in a given cohort after comprehensive chromosomal screening can be used to identify candidates for single embryo transfer.

Methods

Blastocysts from 437 patients underwent trophectoderm biopsy followed by array comparative genomic hybridization. Embryos were then selected for single or double embryo transfer. The number of euploid blastocysts produced and transferred for each patient was recorded, as was clinical pregnancy rate and multiple gestation rate.

Results

In patients with ≤3 euploid blastocysts, clinical pregnancy rate was higher in double, compared to single embryo transfers. However, in patients with ≥4 euploid blastocysts, clinical pregnancy rate was not reduced with single embryo transfer was performed, whereas the multiple gestation rate was greatly reduced.

Conclusions

Size of the euploid embryo cohort is a marker for success in single embryo transfer cycles. Patients who produce at least four euploid blastocysts are outstanding candidates for single embryo transer.