scholarly journals Transfer of hatched blastocyst can result in skewed sex ratio: a retrospective cohort study

2021 ◽  
Author(s):  
Jinliang Zhu ◽  
Ying Lian ◽  
Xinjie Zhuang ◽  
Shengli Lin ◽  
Xiaoying Zheng ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Poor Quality ◽  
Blastocyst Stage ◽  
Neonatal Outcomes ◽  
Blastocyst Transfer ◽  
Female Ratio ◽  
Single Blastocyst Transfer ◽  
Blastocyst Quality

Abstract Background The correlation between blastocyst quality and birthweight, neonatal outcomes is still controversial. There is a significantly higher male: female ratio among good quality blastocysts (advanced trophoderm morphology) but in the expansion degree, the significance for sex ratio is unclear. Methods A total of 617 and 6803 live singleton births resulting from the transfer of fresh and frozen-thawed single blastocysts in the Reproductive Medicine Center of Peking University Third Hospital from 2009 to 2020 were included. Live singleton births from fresh and frozen-thawed single blastocyst transfer were stratified by inner cell mass/trophoderm morphology and degree of blastocoel expansion. Multivariate linear regression was used to analyze the correlation between expansion, inner cell mass/trophoderm morphology, and birthweight, Z score, gestational weeks. Logistic regression was used to analyze the relationship between expansion, ICM/TE morphology and sex, neonatal outcomes. Results There was no significant correlation between birthweight, neonatal outcomes and blastocyst quality in fresh and frozen-thawed single blastocyst transfer cycles. However, the proportion of male infants in the hatched blastocyst (stage-6) group (67.9% vs. 54.2%; p < 0.001) [OR: 1.76 95% CI (1.34–2.32)] and hatching blastocyst (stage-5) group (61.7% vs. 54.2%; p = 0.001) [OR: 1.36 95 C.I (1.14ཞ1.62)] was significantly higher than that in the expanded blastocyst (stage-4) group. Conclusions The transfer of poor-quality blastocysts is unlikely to affect birthweight and neonatal health; however, transfer of stage-6 blastocysts can result in extremely skewed sex ratio.

scholarly journals Does the sex ratio of singleton births after frozen single blastocyst transfer differ according to blastocyst morphology?

2020 ◽  
Author(s):  
Hua Lou ◽  
Na Li ◽  
Xiaoke Zhang ◽  
Ling Sun ◽  
Xingling Wang ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Inner Cell Mass ◽  
Sex Ratios ◽  
Cell Mass ◽  
Male Infant ◽  
Poor Quality ◽  
Blastocyst Transfer ◽  
High Quality ◽  
Chi Square ◽  
Live Births

Abstract Purpose: To investigate the associations between morphological blastocyst parameters and the sex ratio (male:female) of singleton live births resulting from single-blastocyst frozen embryo transfer (FET) cycles. Methods: This retrospective analysis included 1210 couples who underwent single-blastocyst FET of warmed day 5 or 6 blastocysts and achieved a singleton live birth between January 2015 and February 2019. The sex ratios in the different blastocyst groups were compared using the chi-square test. The associations of morphological blastocyst parameters, including the blastocoel expansion, inner cell mass and trophectoderm grades, with the sex ratios of live births were analyzed using multiple regression models. Results: The included female patients had an average age and body mass index of 30.5±4.5 years and 23.6±3.2 kg/m2, respectively. blastocyst transfers occurred on day 5 in 783 cases (64.7%) and day 6 in 427 cases (35.3%). Among the day 5 FET cycles, 55.4% of resulting infants were male and 44.6% were female, while among the day 6 cycles, 54.6% of infants were male and 45.4% were female ( P =0.074). Blastocysts quality was assessed according to morphological parameters, which was divided into high-quality (AA,AB,BB,BC) and poor-quality(AC,BC). High-quality blastocyst transfer was associated with a significantly higher sex ratio (60%, 383/638) relative to poor-quality transfer (49.7%, 284/572) ( P< 0.001). The sex ratio of births resulting from blastocyst transfer differed significantly with respect to the trophectoderm grade ( P <0.001). After adjusting for confounders, a grade B trophectoderm was significantly associated with a higher sex ratio among singleton live births (odds ratio: 0.591, 95% confidence interval: 0.463–0.756, P <0.001; reference: grade C trophectoderm). In contrast, the characteristics of blastocoel expansion and the score of the inner cell mass were not significantly associated with the sex ratio among singleton live births. Conclusions: The sex ratio among singleton live births is affected by the quality of blastocysts. A grade B trophectoderm is associated with a higher probability that a single-blastocyst FET cycle will result in a male infant.

P–259 Blastocyst quality is associated with both the start and the duration of compaction after ICSI

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
K Wouters ◽  
L Va. Landuyt ◽  
M Regin ◽  
H Tournaye ◽  
G Verheyen ◽  
...  
Keyword(s):  
Embryo Quality ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Total Duration ◽  
Time Lapse ◽  
Poor Quality ◽  
Blastocyst Stage ◽  
Human Embryos ◽  
The Poor ◽  
Blastocyst Quality

Abstract Study question Is the start and the total duration of compaction related to embryo quality? Summary answer The timing of the start, the end and the total duration of compaction are associated with blastocyst quality grade in the IVF laboratory. What is known already Preimplantation embryo development follows a programmed timeline during which a series of critical events take place. One event typically occurring on day 3/4 post fertilisation is the formation of adherence junctions between blastomeres in a process called compaction. It is considered the first morphological event in the differentiation process of the mammalian embryo. Evaluation of developmental events are used to optimize the selection of the most competent embryos for transfer and/or cryopreservation in the IVF laboratory. It has already been shown that the time of full compaction is indicative for high-quality blastocysts with a higher implantation rate. Study design, size, duration A single-centre retrospective observational study including 74 ICSI cycles performed in 2020. Injected oocytes were cultured in blastocyst medium (Origio) in the EmbryoScope + (Vitrolife) for 5/6 days. Embryos that reached the blastocyst stage were evaluated for the start of compaction, the time to reach full compaction and the total duration of compaction. These parameters were compared between good- and poor-quality blastocysts; the primary outcome parameter of the study was embryo quality. Participants/materials, setting, methods Only ICSI cycles with ejaculated fresh/frozen-thawed sperm and monitored in time-lapse incubator were included. All MNC, IVM and PGT cycles were excluded. Time zero was the start of ICSI. Good-quality embryos were full and expanded blastocysts with good-quality inner cell mass and trophectoderm (AA, AB, BA and BB according to Gardner and Schoolcraft (1999)). GraphPad Prism was used for statistical analysis. After testing for normality and homogeneity, unpaired t-test or Mann-Whitney test determined significant differences. Main results and the role of chance In this study, of the 528 included 2PN oocytes, 229 (43.4%) reached the blastocyst stage and 299 (56.6%) were arrested. Among the former, 131 (57.2%) blastocysts were classified in the good-quality group and 98 (42.8%) blastocysts in the poor-quality group. In general, human embryos compacted slowly while dividing further and the blastomeres moved during the compaction process. The start of compaction was heterogeneous (between 50.9 and 102.7 hours post ICSI; mean=80.0 hours), as well as the cell number at the initiation (between 4 and 18 blastomeres; mean=12 blastomeres). The time analysis showed that the embryos in the good-quality group started to compact significantly earlier than those in the poor-quality group (mean=78.6 vs 82.2 hours; R²=0.06; p &lt; 0.01). We confirmed that blastocysts in the good-quality group reached full compaction earlier than those in the poor-quality group (mean=86.8 vs 93.8 hours; R²=0.17; p &lt; 0.01). Furthermore, the total duration of compaction was significantly lower in the good-quality than in the poor-quality group (median=7.4 vs 10.7 hours; p &lt; 0.01). Limitations, reasons for caution As this is a retrospective study, the influence of uncontrolled variables cannot be excluded. The absence of the pregnancy outcome and live birth rate is a shortcoming and will be subject of a larger patient-to-patient study. Wider implications of the findings: These results indicate that an earlier start and a shorter duration of compaction are associated with better blastocyst quality. These morphological events can be valuable additional parameters in selecting the embryo of better quality when using a time-lapse incubator. Trial registration number Not applicable

scholarly journals Does Blastocyst Morphology Influence Live Birth Rate after Frozen-thawed Single Euploid Embryo Transfer?

2021 ◽  
Author(s):  
Na Li ◽  
Yichun Guan ◽  
Bingnan Ren ◽  
Yuchao Zhang ◽  
Yulin Du ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Live Birth ◽  
Birth Rate ◽  
Inner Cell Mass ◽  
Medical Center ◽  
Cohort Analysis ◽  
Cell Mass ◽  
Live Birth Rate ◽  
Poor Quality ◽  
Blastocyst Quality

Abstract Objective To investigate whether the morphologic parameters of euploid blastocyst influence the live birth rate (LBR) following single frozen-thawed embryo transfer (FET) cycles? Methods A retrospective cohort analysis involving autologous single FET cycles after preimplantation genetic testing for aneuploidy (PGT-A) through next generation sequencing (NGS) by a university-based reproductive medical center that was performed from June 2017 to September 2019.Women were divided into three age groups (< 30, 30–34 and ≥ 35 years). The primary outcome measure was LBR. Outcomes were compared to determine the association between different blastocyst quality (Good, Average and Poor), inner cell mass (ICM) grade (A and B), and trophectoderm (TE) grade (A, B and C) and LBR. Results We included 232 single FET cycles for analysis, the total LBR was 48.48%. In the youngest group (< 30 years, n = 86), LBR were compared between cycles with various blastocyst quality (72.22% for good quality, 54.55% for average quality and 34.78% for poor quality; P = 0.019), ICM grade (70.59% for grade A and 42.03% for grade B; P = 0.035) and TE grade (85.71% for grade A,57.58% for grade B and 34.78 for grade C; P = 0.015). Similarly, in the 30–34 years group, LBR ranged from 50.00% for good quality to 45.45% for poor quality (P = 0.870), from 35.29% for ICM grade A to 51.22% for ICM grade B (P = 0.291), from 60.00% for TE grade A to 45.45% for TE grade C (P = 0.634). Likewise, in the oldest group (≥ 35years, n = 47), LBR were also comparable between these subgroups, but no significant differences were seen in blastocyst morphologic parameters and LBR (P > 0.05). Conclusion After single FET cycles, the LBR was associated with morphologic parameters of euploid blastocysts, especially in women < 30 years old. However, these differences were not found in women older than 30 years. We suggested that for older women whose embryos undergoing PGT-A with NGS to be euploid have the same development potential regardless of their blastocyst morphology.

104 BIRTH OF FIRST BUFFALO (BUBALUS BUBALS) CALF FOLLOWING EMBRYO SPLITTING AND POLYMERASE CHAIN REACTION SEXING AT BLASTOCYST STAGE

2012 ◽  
Vol 24 (1) ◽  
pp. 164 ◽  
Author(s):  
M. Zhang ◽  
H. H. Chen ◽  
J. W. Tang ◽  
X. W. Liang ◽  
M. T. Chen ◽  
...  
Keyword(s):  
Nested Pcr ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Blastocyst Stage ◽  
Buffalo Calf ◽  
Practical Procedure ◽  
Blastocyst Quality ◽  
Grade 3 ◽  
Vitro Development

Embryo-splitting technology provides an effective procedure for increasing the number of transferable embryos per donor, producing genetically identical offspring and facilitating embryo sexing. The ability to identify the sex of embryos before transfer will offer a reliable, economical and practical procedure for buffalo breeding. In this study, we have assessed the feasibility of production of offspring with controlled sex in buffalo by first comparing the effect of blastocyst quality on the viability of demi-embryos and then identifying the sex of a demi-embryo by multiplex-nested PCR before transfer into the recipient. In vitro-matured buffalo oocytes were fertilized by IVF and cultured to the blastocyst stage for 6 to 7 days as described by Lu et al. (2007 Anim. Reprod. Sci. 100, 192–196). These blastocysts were classified in terms of their developmental pattern and morphology on a scale of 1 to 3 grades as described by McEvoy et al. (1990 Theriogenology 33, 1245–1253). Blastocysts were split into 2 equal parts by a micromanipulation system. Viability of the resulting demi-embryos was confirmed by formation of a blastocoel cavity and definite inner cell mass after culture for 24 h. One of the zone-free demi-embryos derived from a grade-1 blastocyst was cultured in TCM 199 supplemented with 10% fetal bovine serum for another 2 h, then was transplanted to a spontaneous oestrous recipient. The other demi-embryo was used for sexing by multiplex-nested PCR (Fu et al. 2007 Theriogenology 68, 1211–1218). The results showed that grade-1 blastocysts yielded more viable demi-embryos than grade-2 and grade-3 blastocysts [P < 0.01; 73/92 (79.67%) vs 32/76 (47.05%) vs 26/94 (26.53%), respectively]. Transplantation of the presumed-Y demi-embryo derived from grade-1 blastocyst into a recipient resulted in the birth of a male buffalo calf. To the best of our knowledge, this is the first buffalo calf produced following embryo splitting and PCR sexing of the embryo at the blastocyst stage. Successful birth of the desired-sex offspring in the present study indicates the feasibility of using embryo splitting in combination with multiplex-nested PCR sexing to produce offspring of controlled sex in swamp buffalo. However, the quality of embryos before splitting was an important factor governing the in vitro development of viable demi-embryos. This study was supported by the Guangxi Science and Technology R&D Program (0626001-3-1, 0815008-2-4).

scholarly journals Cytoplasmic String Between ICM and mTE Is a Positive Predictor of Clinical Pregnancy and Live Birth Outcomes in Elective Frozen-thawed Single Blastocyst Transfer Cycles: a Time-lapse Study

2020 ◽  
Author(s):  
Bing-Xin Ma ◽  
Lei Jin ◽  
Bo Huang
Keyword(s):  
Birth Outcomes ◽  
Live Birth ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Time Lapse ◽  
Clinical Pregnancy ◽  
Blastocyst Transfer ◽  
Single Blastocyst Transfer ◽  
First Time ◽  
Present Group

Abstract Background: In this study, we aim to investigate whether cytoplasmic string between inner cell mass (ICM) and mural trophectoderm (mTE) is a positive predictor of clinical pregnancy and live birth outcomes.Methods: 1,267 elective frozen-thawed single blastocyst transfer (eSBT) cycles cultured in time-lapse incubation system from January 2018 to May 2019 were involved in the study. Blastocysts were grouped according to the appearance of cytoplasmic strings between ICM and mTE cells, and identified as “Present” and “Absent” groups. In Present group, they were further categorized according to the quantity of cytoplasmic strings between ICM and mTE cells. Clinical pregnancy and live birth outcomes of blastocysts were used to evaluate the effect of cytoplasmic strings between ICM and mTE.Results: The baseline demographic and laboratory features were similar between the Present and Absent groups of cytoplasmic strings between ICM and mTE (P>0.05). According to the time-lapse analysis, cytoplasmic strings between ICM and mTE were more visible among good quality blastocysts. Furthermore, blastocysts with cytoplasmic strings showed a higher clinical pregnancy and live birth rates (P<0.05), and no significant differences were observed in abortion rate and birth weight (P>0.05).Conclusions: Although the previous conclusions of cytoplasmic strings were controversial, the present time-lapse analysis provides the evidence for the first time that cytoplasmic strings between ICM and mTE cells would be a positive predictor of clinical pregnancy and live birth outcomes in elective frozen-thawed single blastocyst transfer cycles.

Does Blastocyst Morphology Influence Live Birth Rate after Frozen-thawed Single Euploid Blastocyst Transfer?

2020 ◽  
Author(s):  
Na Li ◽  
Yichun Guan ◽  
Bingnan Ren ◽  
Yuchao Zhang ◽  
Yulin Du ◽  
...  
Keyword(s):  
Live Birth ◽  
Birth Rate ◽  
Inner Cell Mass ◽  
Statistical Significance ◽  
Cohort Analysis ◽  
Cell Mass ◽  
Live Birth Rate ◽  
Poor Quality ◽  
Significant Difference ◽  
Blastocyst Quality

Abstract Objective To determine whether the morphologic parameters of euploid blastocyst influence the live birth rate (LBR) following single frozen-thawed embryo transfer (FET) cycles? Methods A retrospective cohort analysis involving autologous single FET cycles after next generation sequencing (NGS) based preimplantation genetic testing for aneuploidy (PGT-A) by a large in vitro fertilization (IVF) center that was performed from June 2017 to September 2019.Women were divided into three age groups (< 30, 30–34 and ≥ 35 years old). The primary outcome measure was LBR. Outcomes were compared between different blastocyst quality (Good, Average and Poor), inner cell mass (ICM) grade (A and B), and trophectoderm (TE) grade (A, B and C). Results A total of 232 FET cycles were included, the live birth rate was 48.28%. In the youngest group (< 30 years old, n = 86), LBR were compared between cycles with various blastocyst quality (72.22% for good quality, 54.55% for average quality and 34.78% for poor quality; P = 0.019), ICM grade (70.59% for grade A and 42.03% for grade B; P = 0.035) and TE grade (85.71% for grade A,57.58% for grade B and 34.78 for grade C; P = 0.015). Nevertheless, either in the 30–34 years group (n = 99) or in the oldest group (≥ 35years, n = 47), LBR were also comparable between these subgroups, no significant difference was showed in blastocyst morphologic parameters and LBR (P > 0.05). Furthermore, in the similarly graded euploid blastocysts, there was also no statistical significance in LBR among different age subgroups (P > 0.05). Conclusions In women ≥ 30 years old, euploid blastocyst quality was not associated with the LBR in FET cycles, highlights the development competence of poor-quality euploid blastocysts.

Does Blastocyst Morphology Affect Live Birth Rate After Transfer of Single Euploid Embryo?

2021 ◽  
Author(s):  
Na Li ◽  
Yichun Guan ◽  
Bingnan Ren ◽  
Yuchao Zhang ◽  
Yulin Du ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Live Birth ◽  
Birth Rate ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Live Birth Rate ◽  
Poor Quality ◽  
Average Quality ◽  
Blastocyst Quality ◽  
Euploid Embryo

Abstract Background The aim of this study was to investigate whether the morphologic parameters of blastocyst influence the live birth rate (LBR) of euploid embryos transferred in subsequent single frozen-thawed embryo transfer (FET) cycles? Methods Women who received first preimplantation genetic testing for aneuploidy (PGT-A) and following underwent frozen-thawed single euploid blastocyst transfer cycles from June 2017 to May 2020 were divided into three age groups (< 30, 30–34 and ≥ 35 years). The primary outcome measure was LBR. Outcomes were compared between different blastocyst quality, inner cell mass (ICM) grade, trophectoderm (TE) grade and day of TE biopsy within the same age group. Results In the youngest group (< 30 years, n = 100), LBR were compared between cycles with various blastocyst quality (66.67% for good quality, 65.52% for average quality and 36.36% for poor quality; P = 0.013), ICM grade (61.11% for grade A and 51.22% for grade B; P = 0.466), TE grade (68.75% for grade A,65.00% for grade B and 36.30% for grade C; P = 0.012) and day of TE biopsy (65.38% for Day 5 and 39.58% for Day 6; P = 0.010). Similarly, in the 30–34 years group(n = 121) and the oldest group (≥ 35years, n = 58), LBR were also comparable between these subgroups, but no significant differences were seen between blastocyst morphologic grading and LBR (P > 0.05). Moreover, good quality (adjusted odds ratio [aOR] 3.30; 95% confidence interval [CI], 1.09 ~ 9.99; P = 0.035) and average quality (aOR 3.71; 95%CI, 1.25 ~ 11.01; P = 0.018) embryos were still yielded a significantly higher LBR than poor-quality embryos, TE grade B embryos were also associated with a statistically significantly higher LBR compared with TE grade C embryos (aOR 3.69;95%CI, 1.37 ~ 9.95; P = 0.010) after adjusting for the potential confounding factors. Conclusion Blastocyst quality and trophectoderm grading is a useful predictor of LBR in single frozen-thawed euploid embryo transfer cycles among women < 30 years old. However, these differences were not found in women older than 30 years.

scholarly journals Does Blastocyst Morphology Influence Live Birth Rate After Single Euploid Embryo Transfer?

2021 ◽  
Author(s):  
Na Li ◽  
Yichun Guan ◽  
Bingnan Ren ◽  
Yuchao Zhang ◽  
Yulin Du ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Live Birth ◽  
Birth Rate ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Age Groups ◽  
Live Birth Rate ◽  
Poor Quality ◽  
Preimplantation Genetic Testing ◽  
Blastocyst Quality

Abstract Background: The aim of this study was to investigate whether the morphologic parameters of euploid blastocyst influence the live birth rate (LBR) following single frozen-thawed embryo transfer (FET) cycles?Methods: Women who undergone first preimplantation genetic testing for aneuploidy (PGT-A) and following received single FET cycles from June 2017 to September 2019 were divided into three age groups (<30, 30-34 and ≥35 years). The primary outcome measure was LBR. Outcomes were compared to determine the association among different blastocyst quality (Good, Average and Poor), inner cell mass (ICM) grade (A and B), and trophectoderm (TE) grade (A, B and C) and LBR.Results: In the youngest group (<30 years, n=86), LBR were compared between cycles with various blastocyst quality (72.22% for good quality, 54.55% for average quality and 34.78% for poor quality; P=0.019), ICM grade (70.59% for grade A and 42.03% for grade B; P=0.035) and TE grade (85.71% for grade A,57.58% for grade B and 34.78% for grade C; P=0.015). Similarly, in the 30-34 years group, LBR ranged from 50.00% for good quality to 45.45% for poor quality (P=0.870), from 35.29% for ICM grade A to 51.22% for ICM grade B (P=0.291), from 60.00% for TE grade A to 45.45% for TE grade C (P=0.634). Likewise, in the oldest group (≥35years, n=47), LBR were also comparable between these subgroups, but no significant differences were seen between blastocyst morphologic parameters and LBR (P>0.05). Conclusion: LBR was associated with morphologic parameters of euploid blastocysts, especially in women <30 years old. However, these differences were not found in women older than 30 years.

scholarly journals Cytoplasmic String Between ICM and mTE Is a Positive Predictor of Clinical Pregnancy and Live Birth Outcomes in Elective Frozen-thawed Single Blastocyst Transfer Cycles: A Time-lapse Study

2021 ◽  
Author(s):  
Bingxin Ma ◽  
Lei Jin ◽  
Bo Huang
Keyword(s):  
Birth Outcomes ◽  
Live Birth ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Time Lapse ◽  
Clinical Pregnancy ◽  
Blastocyst Transfer ◽  
Single Blastocyst Transfer ◽  
First Time ◽  
Present Group

Abstract Background: In this study, we aim to investigate whether cytoplasmic string between inner cell mass (ICM) and mural trophectoderm (mTE) is a positive predictor of clinical pregnancy and live birth outcomes.Methods: 1,267 elective frozen-thawed single blastocyst transfer (eSBT) cycles cultured in time-lapse incubation system from January 2018 to May 2019 were involved in the study. Blastocysts were grouped according to the appearance of cytoplasmic strings between ICM and mTE cells, and identified as “Present” and “Absent” groups. In Present group, they were further categorized according to the quantity of cytoplasmic strings between ICM and mTE cells. Clinical pregnancy and live birth outcomes of blastocysts were used to evaluate the effect of cytoplasmic strings between ICM and mTE.Results: The baseline demographic and laboratory features were similar between the Present and Absent groups of cytoplasmic strings between ICM and mTE (P>0.05). According to the time-lapse analysis, cytoplasmic strings between ICM and mTE were more visible among good quality blastocysts. Furthermore, blastocysts with cytoplasmic strings showed a higher clinical pregnancy and live birth rates (P<0.05), and no significant differences were observed in abortion rate and birth weight (P>0.05).Conclusions: Although the previous conclusions of cytoplasmic strings were controversial, the present time-lapse analysis provides the evidence for the first time that cytoplasmic strings between ICM and mTE cells would be a positive predictor of clinical pregnancy and live birth outcomes in elective frozen-thawed single blastocyst transfer cycles.

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