1
|
Di Guardo F, Racca A, Coticchio G, Borini A, Drakopoulos P, Mackens S, Tournaye H, Verheyen G, Blockeel C, Van Landuyt L. Impact of cell loss after warming of human vitrified day 3 embryos on obstetric outcome in single frozen embryo transfers. J Assist Reprod Genet 2022; 39:2069-2075. [PMID: 35857255 PMCID: PMC9474781 DOI: 10.1007/s10815-022-02572-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 07/08/2022] [Indexed: 10/17/2022] Open
Abstract
PURPOSE Does cell loss (CL) after vitrification and warming (V/W) of day 3 embryos have an impact on live birth rate (LBR) and neonatal outcomes? METHOD This retrospective analysis includes cleavage stage day 3 embryos vitrified/warmed between 2011 and 2018. Only single vitrified/warmed embryo transfers were included. Pre-implantation genetic screening, oocyte donation, and age banking were excluded from the analysis. The sample was divided into two groups: group A (intact embryo after warming) and group B (≤ 50% blastomere loss after warming). RESULTS On the total embryos (n = 2327), 1953 were fully intact (83.9%, group A) and 374 presented cell damage (16.1%, group B). In group B, 62% (232/374) of the embryos had lost only one cell. Age at cryopreservation, cause of infertility, insemination procedure, and semen origin were comparable between the two groups. The positive hCG rate (30% and 24.3%, respectively, for intact vs CL group, p = 0.028) and LBR (13.7% and 9.4%, respectively, for intact vs CL group, p = 0.023) per warming cycle were significantly higher for intact embryos. However, LBR per positive hCG was equivalent between intact and damaged embryos (45.6% vs 38.5%, respectively, p = 0.2). Newborn measurements (length, weight, and head circumference at birth) were comparable between the two groups. Multivariate logistic regression showed that the presence of CL is not predictive for LB when adjusting for patients' age. CONCLUSIONS LBR is significantly higher after transfer of an intact embryo compared to an embryo with CL after warming; however, neonatal outcomes are comparable between the two groups.
Collapse
Affiliation(s)
- Federica Di Guardo
- Department of General Surgery and Medical Surgical Specialties, University of Catania, Via Santa Sofia 78, 95125, Catania, Italy.
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090, Brussels, Belgium.
| | - A Racca
- Department of Obstetrics Gynecology and Reproductive Medicine, Dexeus University Hospital, Gran Via de Carles III, 71, 08028, Barcelona, Spain
| | - G Coticchio
- 9.Baby Family and Fertility Center, Via Dante 15, 40125, Bologna, Italy
| | - A Borini
- 9.Baby Family and Fertility Center, Via Dante 15, 40125, Bologna, Italy
| | - P Drakopoulos
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090, Brussels, Belgium
| | - S Mackens
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090, Brussels, Belgium
| | - H Tournaye
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090, Brussels, Belgium
- Department of Obstetrics, Gynecology, Perinatology and Reproduction, Institute of Professional Education, Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation, Trubetskaya str., 8, b. 2, 119992, Moscow, Russia
| | - G Verheyen
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090, Brussels, Belgium
| | - C Blockeel
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090, Brussels, Belgium
| | - L Van Landuyt
- Centre for Reproductive Medicine, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101-1090, Brussels, Belgium
| |
Collapse
|
2
|
Jiang S, Jin W, Zhao X, Xi Q, Chen L, Gao Y, Li W, Kuang Y. The impact of blastomere loss on pregnancy and neonatal outcomes of vitrified-warmed Day3 embryos in single embryo transfer cycles. J Ovarian Res 2022; 15:62. [PMID: 35585606 PMCID: PMC9116052 DOI: 10.1186/s13048-022-00997-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 05/04/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Blastomere loss is a common phenomenon that occurs following cryopreservation. To date, studies have drawn conflicting conclusions regarding the impact of blastomere loss on pregnancy outcomes. Besides, limited information is available concerning the neonatal safety of embryos with blastomere loss. In the present study, we aimed to investigate the impact of blastomere loss on pregnancy and neonatal outcomes of vitrified/warmed Day3 cleavage-stage embryos in single embryo transfer cycles. METHODS This retrospective cohort study included all vitrified/warmed D3 cleavage-stage single frozen-thawed embryo transfer (FET) cycles between April 2015 and February 2021. We compared pregnancy and subsequent neonatal outcomes between the intact embryos group and the blastomere loss group in single FET cycles. RESULTS A total of 6287 single FET cycles were included in the study, in which 5873 cycles were classified into the intact embryo group and 414 cycles were classified into the blastomere loss group. The outcomes of the blastomere loss group were significantly inferior to those of the intact embryo group, in terms of implantation/biochemical pregnancy/clinical pregnancy/ongoing pregnancy rate and live birth rate per embryo transfer cycle/per clinical pregnancy. Further binary logistic regression confirmed that blastomere loss was negatively associated with live birth. Moreover, the blastomere loss group presented with an elevated early miscarriage rate. The neonatal conditions were broadly similar between the two groups. Additionally, multiple binary logistic regression analysis demonstrated that primary infertility and intracytoplasmic sperm injection (ICSI) were common influencing factors of blastomere loss (aOR 1.447, 95% CI 1.038-2.019, P = 0.029; aOR: 1.388, 95% CI: 1.044-51.846, P = 0.024). CONCLUSIONS The transfer of vitrified/warmed D3 embryos with blastomere loss is related to impaired embryo developmental potentials and reduced probabilities of conception. Moreover, even if the embryos with blastomere loss have implanted and reached clinical pregnancies, they present with a lower possibility of developing to live birth owing to a higher early miscarriage rate. However, once the embryos with blastomere loss result in a live birth, no adverse neonatal outcomes are observed. Primary infertility and ICSI were found to be risk factors for blastomere loss.
Collapse
Affiliation(s)
- Shutian Jiang
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Wei Jin
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Xinxi Zhao
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Qianwen Xi
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Li Chen
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Yining Gao
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China
| | - Wenzhi Li
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China.
| | - Yanping Kuang
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, China.
| |
Collapse
|
3
|
Wang YJ, Liu WJ, Fan L, Li ZT, Huang YQ, Chen CQ, Liu D, Zhang XQ, Liu FH. The impacts of the number of prefreeze and postthaw blastomeres on embryo implantation potential: A systematic analysis. Medicine (Baltimore) 2020; 99:e19591. [PMID: 32221078 PMCID: PMC7220464 DOI: 10.1097/md.0000000000019591] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
To systematically analyze the potential of embryo implantation through comparison between the number of surviving blastomeres, the growth, and implantation rate.Retrospective analysis on implantation rate and the growth of prefreeze-postthaw embryos with different blastomeres in 1487 frozen embryo transfer cycles.In groups of postthaw embryos without damage, implantation rate and the average number of blastomere growth increased significantly with increasing number of blastomeres. The implantation rate and the number of blastomeres of embryos with 8-8c (the number of blastomeres in prefreeze embryo-the number of blastomeres in postthaw embryo) continued to grow at a significantly higher rate than that of 5-5c and 6-6c (P < .05). In groups of embryos with the same number of blastomeres before freezing and with partial damage after resuscitation, the implantation rates were lower and the average numbers of blastomere growth reduced as the number of damaged blastomeres increased. For embryos with good quality before freezing, 1 to 3 damaged blastomeres in postthawed embryos did not affect the development and implantation rate. Both implantation rate and growth rate of embryos with 8-6c were significantly higher than those of embryos with 6-6c (P < .05).The number of surviving blastomeres and growth in frozen-thawed embryos could be important index to predict embryo development potential and clinical outcome of implantation. For embryos with good quality, a small amount of damaged blastomeres would not weaken embryo development potential and implantation rate after being thawed.
Collapse
|
4
|
Ramezanali F, Arabipoor A, Hafezi M, Salman-Yazdi R, Zolfaghari Z, Asharfi M. Serum estradiol level on trigger day impacts clinical pregnancy rate in modified natural frozen embryo transfer cycles. Int J Gynaecol Obstet 2019; 145:312-318. [PMID: 30916782 DOI: 10.1002/ijgo.12806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 09/15/2018] [Accepted: 03/19/2019] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To examine the predictive value of serum estradiol and progesterone on the day of human chorionic gonadotropin (hCG) administration and embryo transfer for clinical pregnancy rate in modified natural-cycle frozen embryo transfer (NC-FET). METHODS In a longitudinal prospective study, all eligible women who underwent NC-FET cycles with hCG triggering in Royan Institute, Tehran, Iran, from June 1, 2015, to December 31, 2016, were evaluated. Serum estradiol and progesterone levels were measured at menstrual cycle initiation, on day of trigger with hCG, on day of embryo transfer, and in pregnant women every 7 days until the observation of a gestational sac with embryonic heartbeat. RESULTS In total, 101 modified natural FET cycles were assessed, and the clinical pregnancy and live birth rates achieved were 34 (33.6%) and 32 (31.6%), respectively. The changes in estradiol level during early pregnancy showed an increase by an average of 200 pg/mL per week. Multivariable logistic regression analysis showed that only the estradiol level on the hCG day was a significant predictive variable for clinical pregnancy following NC-FET (P=0.04). CONCLUSION Estradiol level on the day of hCG trigger predicted the clinical pregnancy rates after modified NC-FET; this likely mirrored the developmental competence of the corpus luteum and an appropriate luteal structure-function.
Collapse
Affiliation(s)
- Fariba Ramezanali
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran
| | - Arezoo Arabipoor
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran
| | - Maryam Hafezi
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran
| | - Reza Salman-Yazdi
- Department of Andrology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Zahra Zolfaghari
- Department of Epidemiology and Reproductive Health, Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Mahnaz Asharfi
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran.,Department of Obstetrics and Gynecology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
5
|
Griffin DK, Ogur C. Chromosomal analysis in IVF: just how useful is it? Reproduction 2018; 156:F29-F50. [PMID: 29945889 DOI: 10.1530/rep-17-0683] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 03/23/2018] [Indexed: 12/11/2022]
Abstract
Designed to minimize chances of genetically abnormal embryos, preimplantation genetic diagnosis (PGD) involves in vitro fertilization (IVF), embryo biopsy, diagnosis and selective embryo transfer. Preimplantation genetic testing for aneuploidy (PGT-A) aims to avoid miscarriage and live born trisomic offspring and to improve IVF success. Diagnostic approaches include fluorescence in situ hybridization (FISH) and more contemporary comprehensive chromosome screening (CCS) including array comparative genomic hybridization (aCGH), quantitative polymerase chain reaction (PCR), next-generation sequencing (NGS) and karyomapping. NGS has an improved dynamic range, and karyomapping can detect chromosomal and monogenic disorders simultaneously. Mosaicism (commonplace in human embryos) can arise by several mechanisms; those arising initially meiotically (but with a subsequent post-zygotic 'trisomy rescue' event) usually lead to adverse outcomes, whereas the extent to which mosaics that are initially chromosomally normal (but then arise purely post-zygotically) can lead to unaffected live births is uncertain. Polar body (PB) biopsy is the least common sampling method, having drawbacks including cost and inability to detect any paternal contribution. Historically, cleavage-stage (blastomere) biopsy has been the most popular; however, higher abnormality levels, mosaicism and potential for embryo damage have led to it being superseded by blastocyst (trophectoderm - TE) biopsy, which provides more cells for analysis. Improved biopsy, diagnosis and freeze-all strategies collectively have the potential to revolutionize PGT-A, and there is increasing evidence of their combined efficacy. Nonetheless, PGT-A continues to attract criticism, prompting questions of when we consider the evidence base sufficient to justify routine PGT-A? Basic biological research is essential to address unanswered questions concerning the chromosome complement of human embryos, and we thus entreat companies, governments and charities to fund more. This will benefit both IVF patients and prospective parents at risk of aneuploid offspring following natural conception. The aim of this review is to appraise the 'state of the art' in terms of PGT-A, including the controversial areas, and to suggest a practical 'way forward' in terms of future diagnosis and applied research.
Collapse
Affiliation(s)
- Darren K Griffin
- School of BiosciencesCentre for Interdisciplinary Studies of Reproduction, University of Kent, Canterbury, UK
| | - Cagri Ogur
- Bahceci Genetic Diagnosis Centerİstanbul, Turkey.,Department of BioengineeringYildiz Technical University, İstanbul, Turkey
| |
Collapse
|
6
|
Colaco S, Sakkas D. Paternal factors contributing to embryo quality. J Assist Reprod Genet 2018; 35:1953-1968. [PMID: 30206748 PMCID: PMC6240539 DOI: 10.1007/s10815-018-1304-4] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 08/30/2018] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Advancing maternal and paternal age leads to a decrease in fertility, and hence, many infertile couples opt for assisted reproductive technologies [ART] to achieve biological parenthood. One of the key determinants of achieving a live outcome of ART, embryo quality, depends on both the quality of the oocyte and sperm that have created the embryo. Several studies have explored the effect of oocyte parameters on embryo quality, but the effects of sperm quality on the embryo have not been comprehensively evaluated. METHOD In this review, we assess the effect of various genetic factors of paternal origin on the quality and development of the embryo. RESULTS The effects of sperm aneuploidy, sperm chromatin structure, deoxyribonucleic acid [DNA] fragmentation, role of protamines and histones, sperm epigenetic profile, and Y chromosome microdeletions were explored and found to negatively affect embryo quality. CONCLUSION We propose that careful assessment of spermatozoal parameters is essential to achieve embryo development and a healthy live birth. However, the heterogeneity in test results and the different approaches of assessing a single sperm parameter highlight the need for more research and the development of standardized protocols to assess the role of sperm factors affecting embryo quality.
Collapse
Affiliation(s)
- Stacy Colaco
- Molecular and Cellular Biology Laboratory, Indian Council of Medical Research-National Institute for Research in Reproductive Health, JM Street, Parel, Mumbai, 400012, India.
| | | |
Collapse
|
7
|
Wu YT, Li C, Zhu YM, Zou SH, Wu QF, Wang LP, Wu Y, Yin R, Shi CY, Lin J, Jiang ZR, Xu YJ, Su YF, Zhang J, Sheng JZ, Fraser WD, Liu ZW, Huang HF. Outcomes of neonates born following transfers of frozen-thawed cleavage-stage embryos with blastomere loss: a prospective, multicenter, cohort study. BMC Med 2018; 16:96. [PMID: 29914496 PMCID: PMC6006714 DOI: 10.1186/s12916-018-1077-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 05/15/2018] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Despite limited information on neonatal safety, the transfer of frozen-thawed cleavage-stage embryos with blastomere loss is common in women undergoing in vitro fertilization. We aimed to evaluate the pregnancy outcomes and safety of frozen-thawed cleavage-stage embryos with blastomere loss. METHODS This prospective, multicenter, cohort study included all frozen-thawed cleavage-stage embryo transfer (FET) cycles between 2002 and 2012. Pregnancy outcomes and subsequent neonatal outcomes were compared between FET cycles with intact embryos and those with blastomere loss. RESULTS A total of 12,105 FET cycles were included in the analysis (2259 cycles in the blastomere loss group and 9846 cycles in the intact embryo group). The blastomere loss group showed significantly poorer outcomes with respect to implantation, pregnancy, and live birth rates than the intact embryo group. However, following embryo implantation, the two groups were similar with respect to live birth rates per clinical pregnancy. Among multiple pregnancies (4229 neonates), neonates from the blastomere loss group were at an increased risk of being small for gestational age (aOR = 1.50, 95% CI 1.00-2.25) compared to those from the intact group. A similar trend was observed among singletons (aOR = 1.84, 95% CI 0.99-3.37). No associations were found between blastomere loss and the subsequent occurrence of congenital anomalies or neonatal mortality. However, neonates from the blastomere loss group were at an increased risk of transient tachypnea of the newborn (aOR = 5.21, 95% CI 2.42-11.22). CONCLUSIONS The transfer of embryos with blastomere loss is associated with reduced conception rates. Once the damaged embryos have implanted, pregnancies appear to have the same probability of progressing to live birth but with an increased risk of small for gestational age neonates and transient tachypnea of the newborn. STUDY REGISTRATION This study was retrospectively registered at Chinese Clinical Trial Registry. Registration number: ChiCTR-OOC-16007753 . Registration date: 13 January 2016.
Collapse
Affiliation(s)
- Yan-Ting Wu
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Cheng Li
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi-Min Zhu
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Zhejiang, China
| | - Shu-Hua Zou
- Department of Reproductive Medicine, Qingdao Women and Children's Hospital, Shandong, China
| | - Qiong-Fang Wu
- Department of Reproductive Medicine, Jiangxi Maternal and Child Health Hospital, Jiangxi, China
| | - Li-Ping Wang
- Department of Reproductive Medicine, Jiaxing Maternity and Child Health Care Hospital, Zhejiang, China
| | - Yan Wu
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Zhejiang, China
| | - Rong Yin
- Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Zhejiang, China
| | - Chao-Yi Shi
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jing Lin
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zi-Ru Jiang
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi-Jing Xu
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yun-Fei Su
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jian Zhang
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China.,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jian-Zhong Sheng
- Department of Pathology and Pathophysiology, School of Medicine, Zhejiang University, Zhejiang, China.,Key Laboratory of Reproductive Genetics, Ministry of Education (Zhejiang University), Zhejiang, China
| | - William D Fraser
- Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke (CRCHUS) and Department of Obstetrics and Gynecology, University of Sherbrooke, Sherbrooke, QC, Canada
| | - Zhi-Wei Liu
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China. .,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - He-Feng Huang
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, No. 910 Hengshan Rd, Shanghai, 200030, China. .,Institute of Embryo-Fetal Original Adult Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| |
Collapse
|
8
|
Vázquez-Diez C, FitzHarris G. Causes and consequences of chromosome segregation error in preimplantation embryos. Reproduction 2018; 155:R63-R76. [DOI: 10.1530/rep-17-0569] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 10/19/2017] [Accepted: 11/06/2017] [Indexed: 01/04/2023]
Abstract
Errors in chromosome segregation are common during the mitotic divisions of preimplantation development in mammalian embryos, giving rise to so-called ‘mosaic’ embryos possessing a mixture of euploid and aneuploid cells. Mosaicism is widely considered to be detrimental to embryo quality and is frequently used as criteria to select embryos for transfer in human fertility clinics. However, despite the clear clinical importance, the underlying defects in cell division that result in mosaic aneuploidy remain elusive. In this review, we summarise recent findings from clinical and animal model studies that provide new insights into the fundamental mechanisms of chromosome segregation in the highly unusual cellular environment of early preimplantation development and consider recent clues as to why errors should commonly occur in this setting. We furthermore discuss recent evidence suggesting that mosaicism is not an irrevocable barrier to a healthy pregnancy. Understanding the causes and biological impacts of mosaic aneuploidy will be pivotal in the development and fine-tuning of clinical embryo selection methods.
Collapse
|
9
|
Fernandez Gallardo E, Spiessens C, D’Hooghe T, Debrock S. Effect of day 3 embryo morphometrics and morphokinetics on survival and implantation after slow freezing-thawing and after vitrification-warming: a retrospective cohort study. Reprod Biol Endocrinol 2017; 15:79. [PMID: 28974230 PMCID: PMC5627418 DOI: 10.1186/s12958-017-0299-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/22/2017] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Morphometric and morphokinetic evaluation of in vitro cultured human embryos allows evaluation without time restriction and reduces intra- and inter-observer variability. Even though these technologies have been reported to improve the quality of cleavage stage embryo evaluation during fresh culture, possible advantages in the evaluation of cryopreserved embryos have been scarcely explored. This study aims to compare morphometric and morphokinetic parameters between slow frozen and vitrified embryos and to determine their relationship to embryo survival and implantation rate (IR) after thawing/warming. METHODS During fresh culture, morphometric characteristics (Total Cell Volume (TCV), symmetry, fragmentation and number of blastomeres) were measured in 286 thawed/warmed embryos. Likewise, after thawing/warming, similar morphometric characteristics were measured in 135 survived embryos. Moreover, morphokinetic parameters (time to mitosis resumption and time to compaction) were measured in 90 embryos after thawing/warming. Then, using linear regression, we investigated the differences between vitrified and slow frozen embryos and the relation of the measured characteristics to embryo survival and IR. Statistical corrections were applied to account for data clustering and for multiple testing. RESULTS Vitrified embryos resume mitosis and start compaction significantly earlier than slow frozen embryos. Mitosis resumption rate was 82% for vitrified and 63% for slow frozen embryos and median time to mitosis resumption was 7.6 h and 13.1 h (p = 0.02), respectively. Compaction rate was 62% in vitrified and only 23% in slow frozen embryos. Median time to compaction was 18.1 h for vitrified embryos but, for slow frozen could not be computed since less than half of the slow frozen embryos reached compaction (p = 0.0001). Moreover, intact embryos resume mitosis significantly earlier than not intact ones regardless of the freezing method (rate: 79% vs. 66%, median time: 7.6 h vs 14.6 h, respectively, p = 0.03). Regarding morphometrics, slow frozen embryos showed lower TCV and higher blastomere symmetry after thawing than vitrified embryos despite having similar blastomere number. IR was related to blastomere number at cryopreservation in slow frozen embryos, but not in vitrified ones. CONCLUSIONS Interestingly, vitrified/warmed embryos undergo mitosis resumption and compaction significantly earlier than slow frozen/thawed embryos. However, the clinical use of this morphokinetic parameters still remains to be investigated in larger studies. TRIAL REGISTRATION Retrospectively registered on December 15, 2015 NCT02639715 .
Collapse
Affiliation(s)
- Elia Fernandez Gallardo
- 0000 0004 0626 3338grid.410569.fKU Leuven – University of Leuven, University Hospitals Leuven, Leuven University Fertility Center, Herestraat 49, B-3000 Leuven, Belgium
| | - Carl Spiessens
- 0000 0004 0626 3338grid.410569.fKU Leuven – University of Leuven, University Hospitals Leuven, Leuven University Fertility Center, Herestraat 49, B-3000 Leuven, Belgium
| | - Thomas D’Hooghe
- 0000 0004 0626 3338grid.410569.fKU Leuven – University of Leuven, University Hospitals Leuven, Leuven University Fertility Center, Herestraat 49, B-3000 Leuven, Belgium
| | - Sophie Debrock
- 0000 0004 0626 3338grid.410569.fKU Leuven – University of Leuven, University Hospitals Leuven, Leuven University Fertility Center, Herestraat 49, B-3000 Leuven, Belgium
| |
Collapse
|
10
|
Zheng X, Chen Y, Yan J, Wu Y, Zhuang X, Lin S, Zhu J, Lian Y, Qiao J, Liu P. Effect of repeated cryopreservation on human embryo developmental potential. Reprod Biomed Online 2017; 35:627-632. [PMID: 29102427 DOI: 10.1016/j.rbmo.2017.08.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 08/05/2017] [Accepted: 08/08/2017] [Indexed: 11/26/2022]
Abstract
Repeated cryopreservation of surplus embryos from frozen-thawed cycles should occasionally be considered. The purpose of this retrospective cohort study was to evaluate the pregnancy and perinatal outcome of repeated cryopreservation by vitrification of human blastocysts derived from slowly frozen-thawed day 3 embryos. In total, 571 vitrified-warmed blastocyst transfer cycles were investigated. The vitrified-warmed blastocysts were derived from slowly frozen-thawed cleavage embryos (twice-cryopreserved group) or fresh embryos (control group) cultured to the blastocyst stage. Age, body mass index, endometrial thickness, blastocyst developmental rate and number of embryos transferred were not significantly different between twice-cryopreserved and control groups. Clinical pregnancy and implantation rates were also similar. Compared with controls, the miscarriage rate was significantly higher in the twice-cryopreserved group (33.93% versus 19.07%, P = 0.017). This resulted in a significantly lower live birth rate in the twice-cryopreserved group than in controls (29.13% versus 39.18, P = 0.038). No differences were observed in mean gestational age, birthweight and sex ratio of newborns between groups. In conclusion, acceptable clinical pregnancy outcomes may be expected from transfer of twice-cryopreserved human embryos. While the neonatal outcome is not affected, the correlation between the risk of higher pregnancy loss and repeated cryopreservation needs further investigation.
Collapse
Affiliation(s)
- Xiaoying Zheng
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Yuan Chen
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Jie Yan
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Yuqi Wu
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Xinjie Zhuang
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Shengli Lin
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Jinliang Zhu
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Ying Lian
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Jie Qiao
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China
| | - Ping Liu
- Centre of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University, Third Hospital, Beijing 100191, China; Key Laboratory of Assisted Reproduction, Ministry of Education, Beijing 100191, China.
| |
Collapse
|
11
|
Takahashi T, Hasegawa A, Igarashi H, Amita M, Matsukawa J, Takehara I, Suzuki S, Nagase S. Prognostic factors for patients undergoing vitrified-warmed human embryo transfer cycles: a retrospective cohort study. HUM FERTIL 2016; 20:140-146. [PMID: 27876421 DOI: 10.1080/14647273.2016.1255786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
We examined the prognostic factors for pregnancy in 210 vitrified-warmed embryo transfer (ET) cycles in 121 patients. The univariate analysis showed that age, gravida, the number of cycles associated with infertility caused by endometriosis, the number of previous assisted reproductive technology (ART) treatment cycles, and the number of ICSI procedures were significantly lower in pregnant cycles compared with non-pregnant cycles. The percentages of ET using at least one intact embryo and of ET using at least one embryo that had developed further after warming were significantly higher in pregnant cycles compared with non-pregnant cycles. Multivariate logistic regression analysis showed that previous ART treatment cycles, ET with at least one intact embryo, and ET using at least one embryo that had developed further were independent prognostic factors for pregnancy in vitrified-warmed ET cycles. We conclude that fewer previous ART treatment cycles, ET using at least one intact embryo, and ET with embryos that have developed further after warming might be favourable prognostic factors for pregnancy in vitrified-warmed ET cycles.
Collapse
Affiliation(s)
- Toshifumi Takahashi
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| | - Ayumi Hasegawa
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| | - Hideki Igarashi
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| | - Mitsuyoshi Amita
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| | - Jun Matsukawa
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| | - Isao Takehara
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| | - Satoko Suzuki
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| | - Satoru Nagase
- a Department of Obstetrics and Gynecology , Yamagata University Faculty of Medicine , Yamagata , Japan
| |
Collapse
|
12
|
Fernandez Gallardo E, Spiessens C, D’Hooghe T, Debrock S. Effect of embryo morphology and morphometrics on implantation of vitrified day 3 embryos after warming: a retrospective cohort study. Reprod Biol Endocrinol 2016; 14:40. [PMID: 27475526 PMCID: PMC4967519 DOI: 10.1186/s12958-016-0175-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 07/22/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Characteristics routinely used to evaluate embryo quality after thawing include number of blastomeres survived and presence of mitosis resumption after overnight culture. It is unknown to which extent symmetry and fragmentation affect implantation after warming and whether application of stricter criteria either before vitrification or after warming would improve implantation rate (IR) of vitrified/warmed embryos. This study aimed to find new parameters to improve selection criteria for vitrification and for transfer after warming. METHODS Firstly, we evaluated standard morphological characteristics (intact survival, mitosis resumption, number of blastomeres, symmetry and fragmentation) of 986 warmed day 3 embryos and, from a subset of 654, we evaluated morphometric characteristics (fragmentation, symmetry and volume change). Secondly, we tested the hypothesis that IR of day 3 vitrified/warmed embryos is influenced by morphometric characteristics. IR per embryo transferred was calculated using embryos that were transferred in a single embryo transfer (SET) or a double embryo transfer (DET) with either 0 or 100 % implantation (830/986). We investigated the significant differences in IR between the different categories of a specific characteristic. These categories were based on our standard embryo evaluation system. The statistical tests Chi-square, Fisher's exact or Cochrane-Armitage were used according to the type and/or categories of the variable. RESULTS The 986 embryos were transferred in 671 FET cycles with 16.9 % (167/986) IR. After exclusion of DET with 1 embryo implanted, IR per embryo transferred was 12.4 % (103/830). Embryo symmetry, fragmentation and volume change in vitrified/warmed day 3 embryos were not associated with IR. However, when mitosis resumption was present after overnight culture, intact embryos reached significantly higher IR than non-intact embryos and only when the embryo compacted after overnight culture the number of cells damaged after warming had no effect on IR. Concretely, embryos with 8 cells after warming or >9 cells after overnight culture-including compacted embryos-reached the highest IR (>15 %) while embryos with <6 cells after warming or with ≤6 cells after overnight culture had extremely low IR (<1 %). CONCLUSIONS IR of vitrified embryos is determined by the number of cells lost, by the occurrence of mitosis resumption, and by the specific number of blastomeres present but not by fragmentation, blastomere symmetry or volume change. Unselecting embryos for cryopreservation because of fragmentation >10 % and/or symmetry < 75 % only leads to unwanted loss of embryos with acceptable implantation potential. TRIAL REGISTRATION Retrospectively registered NCT02639715 .
Collapse
Affiliation(s)
- Elia Fernandez Gallardo
- University Hospitals Leuven, Leuven University Fertility Center, KU Leuven—University of Leuven, Herestraat 49, Leuven, B-3000 Belgium
| | - Carl Spiessens
- University Hospitals Leuven, Leuven University Fertility Center, KU Leuven—University of Leuven, Herestraat 49, Leuven, B-3000 Belgium
| | - Thomas D’Hooghe
- University Hospitals Leuven, Leuven University Fertility Center, KU Leuven—University of Leuven, Herestraat 49, Leuven, B-3000 Belgium
| | - Sophie Debrock
- University Hospitals Leuven, Leuven University Fertility Center, KU Leuven—University of Leuven, Herestraat 49, Leuven, B-3000 Belgium
| |
Collapse
|
13
|
Van Landuyt L, Van de Velde H, De Vos A, Haentjens P, Blockeel C, Tournaye H, Verheyen G. Influence of cell loss after vitrification or slow-freezing on further in vitro development and implantation of human Day 3 embryos. Hum Reprod 2013; 28:2943-9. [DOI: 10.1093/humrep/det356] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
14
|
Rajagopal K, Chilbule SK, Madhuri V. Viability, proliferation and phenotype maintenance in cryopreserved human iliac apophyseal chondrocytes. Cell Tissue Bank 2013; 15:153-63. [PMID: 23934174 DOI: 10.1007/s10561-013-9387-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Accepted: 07/16/2013] [Indexed: 11/24/2022]
Abstract
Cryopreservation preserves cells at low temperature and creates a reserve for future use while executing the clinical translation. Unlike articular chondrocyte, cryopreservation protocol and its outcome are not described in iliac apophyseal chondrocytes, a potential source of chondrocytes in cartilage engineering. This study for the first time describes the cryopreservation of human iliac apophyseal chondrocytes. Four cartilage samples were procured from iliac crests of children undergoing hip surgery after consent. The total chondrocyte yield was divided into two groups. First group was grown as monolayer while second group was cryopreserved following the slow cooling method in the medium containing 10 % Dimethyl sulfoxide for 3 months. Group two cells were also grown as a monolayer following thawing. Viability, time to confluence, population doubling time and phenotype maintenance were compared for both the groups. Viability was 65.75 % after 3 months of cryopreservation at -196 °C, as compared to 94.19 % for fresh chondrocytes (p = 0.001). Fresh and cryopreserved cells reached confluence on 10th and 15th day of culture respectively. Population doubling time was significantly more in fresh than cryopreserved chondrocytes on 10th (p = 0.0006) and 15th day (p = 0.0002) in culture. Both fresh and cryopreserved cells maintain their chondrocyte phenotype as assessed by immunocytochemistry. Relative gene expression by real time polymerase chain reaction showed similar upregulation of mRNA of Collagen 2, SOX 9, Aggrecan and Collagen 1 in cryopreserved chondrocyte as compared to fresh chondrocyte. Iliac apophyseal chondrocytes cryopreserved for 3 months maintained the phenotype successfully 2 weeks after thawing in culture. The viability and proliferation rates after thawing were adequate for a clinical translation of these cells.
Collapse
Affiliation(s)
- Karthikeyan Rajagopal
- Paediatric Orthopaedics Unit, Department of Orthopaedics, Christian Medical College, Vellore, 632004, Tamil Nadu, India,
| | | | | |
Collapse
|
15
|
The Alpha consensus meeting on cryopreservation key performance indicators and benchmarks: proceedings of an expert meeting. Reprod Biomed Online 2012; 25:146-67. [DOI: 10.1016/j.rbmo.2012.05.006] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 05/11/2012] [Accepted: 05/17/2012] [Indexed: 11/20/2022]
|
16
|
Effect of HCG-day serum progesterone and oestradiol concentrations on pregnancy outcomes in GnRH agonist cycles. Reprod Biomed Online 2012; 24:511-20. [DOI: 10.1016/j.rbmo.2012.02.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 01/27/2012] [Accepted: 02/02/2012] [Indexed: 11/20/2022]
|
17
|
Ming L, Liu P, Qiao J, Lian Y, Zheng X, Ren X, Huang J, Wu Y. Synchronization between embryo development and endometrium is a contributing factor for rescue ICSI outcome. Reprod Biomed Online 2012; 24:527-31. [PMID: 22480904 DOI: 10.1016/j.rbmo.2012.02.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 01/31/2012] [Accepted: 02/01/2012] [Indexed: 11/18/2022]
Abstract
Recent evidence shows that the outcome of rescue intracytoplasmic sperm injection (ICSI) is unsatisfactory on account of a poor clinical pregnancy rate. These outcomes may be due to either the in-vitro ageing of cultured oocytes before ICSI or the asynchrony between the embryo developmental stage and the endometrial secretory pattern. To address the latter issue, this study performed a retrospective analysis of 534 fresh cycles after rescue ICSI and 64 frozen-thawed cycles in subsequent treatment. Rescue ICSI cycles were divided into three groups: group I included 469 fresh embryo-transfer (FET) cycles; group II included 74 FET cycles in which supernumerary good-quality embryos were also cryopreserved; and group III included 64 frozen-thawed transfer cycles. Group III was considered to have achieved better synchronization than group II. As a result, significantly higher clinical pregnancy (29.69%, 19/64 versus 10.81%, 8/74) and implantation (13.33%, 22/165 versus 5.13%, 8/156) rates were achieved in group III compared with group II (both P<0.05). Therefore, synchronization of embryo development with the endometrium is considered a contributing factor for rescue ICSI outcome. It is recommended that embryos derived from rescue ICSI cycles should be cryopreserved and subsequently used in frozen-thawed cycles. Intracytoplasmic sperm injection (ICSI) of unfertilized 1-day-old oocytes, called rescue ICSI, has frequently been performed in some infertility centres, when fertilization failure sometimes occurs in conventional IVF cycles. Recent studies showed that the outcome of rescue ICSI was unsatisfactory due to poor clinical pregnancy rates. One reason could be asynchrony between the embryo developmental stage and the endometrial secretory pattern. To address this issue, we performed a retrospective analysis of 534 fresh cycles after rescue ICSI (from January 2006 to January 2011) and 64 frozen-thawed transfer cycles in subsequent treatment (from January 2006 to May 2011) in our infertility centre. In this study, rescue ICSI cycles were divided into three groups. As there was no significant difference in women's age (31.22 ± 3.38 versus 31.11 ± 3.27 years) between groups II and III, we principally compared these two groups. Group II included 74 fresh embryo transfer cycles, in which supernumerary good-quality embryos were cryopreserved, and group III included 64 frozen-thawed transfer cycles. Group III was considered to have better synchronization than group II. As a result, significantly higher clinical pregnancy (29.69% versus 10.81%) and implantation (13.33% versus 5.13%) rates were achieved in group III compared with group II. Therefore, endometrial synchronization is considered a contributing factor for rescue ICSI outcome and embryos derived from rescue ICSI cycles should be cryopreserved and subsequently used in frozen-thawed cycles.
Collapse
Affiliation(s)
- Li Ming
- Center of Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, People’s Republic of China
| | | | | | | | | | | | | | | |
Collapse
|