Selection of competent blastocysts for transfer by combining time-lapse monitoring and array CGH testing for patients undergoing preimplantation genetic screening: a prospective study with sibling oocytes

BMC Medical Genomics

Jiaen Liu¹  Rifaat D Salem²  Yanping Kuang⁴  Xiaohong Liu¹  Shala A Salem²  John Zhang³  Zhihong Yang⁵ 

[1] IVF and REI Division, Jia En De Yun Hospital, Beijing, People’s Republic of China;ART and REI Division, Pacific Reproductive Center, Torrance, CA, USA;ART Division, New Hope Fertility Center, New York, NY, USA;ART Department, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China;ZytoGen Global Genetics Institute, Timonium, MD 21093, USA

关键词: Miscarriage;    Implantation;    Ploidy;    PGS;    Array CGH;    Time-lapse monitoring;   

Others  :  796965
DOI  :  10.1186/1755-8794-7-38

 received in 2013-10-28, accepted in 2014-06-12,  发布年份 2014

【 摘 要 】

Background

Recent advances in time-lapse monitoring in IVF treatment have provided new morphokinetic markers for embryonic competence. However, there is still very limited information about the relationship between morphokinetic parameters, chromosomal compositions and implantation potential. Accordingly, this study aimed at investigating the effects of selecting competent blastocysts for transfer by combining time-lapse monitoring and array CGH testing on pregnancy and implantation outcomes for patients undergoing preimplantation genetic screening (PGS).

Methods

A total of 1163 metaphase II (MII) oocytes were retrieved from 138 PGS patients at a mean age of 36.6 ± 2.4 years. These sibling MII oocytes were then randomized into two groups after ICSI: 1) Group A, oocytes (n = 582) were cultured in the time-lapse system and 2) Group B, oocytes (n = 581) were cultured in the conventional incubator. For both groups, whole genomic amplification and array CGH testing were performed after trophectoderm biopsy on day 5. One to two euploid blastocysts within the most predictive morphokinetic parameters (Group A) or with the best morphological grade available (Group B) were selected for transfer to individual patients on day 6. Ongoing pregnancy and implantation rates were compared between the two groups.

Results

There were significant differences in clinical pregnancy rates between Group A and Group B (71.1% vs. 45.9%, respectively, p = 0.037). The observed implantation rate per embryo transfer significantly increased in Group A compared to Group B (66.2% vs. 42.4%, respectively, p = 0.011). Moreover, a significant increase in ongoing pregnancy rates was also observed in Group A compared to Group B (68.9% vs. 40.5%. respectively, p = 0.019). However, there was no significant difference in miscarriage rate between the time-lapse system and the conventional incubator (3.1% vs. 11.8%, respectively, p = 0.273).

Conclusions

This is the first prospective investigation using sibling oocytes to evaluate the efficiency of selecting competent blastocysts for transfer by combining time-lapse monitoring and array CGH testing for PGS patients. Our data clearly demonstrate that the combination of these two advanced technologies to select competent blastocysts for transfer results in improved implantation and ongoing pregnancy rates for PGS patients.

【 授权许可】

   
2014 Yang et al.; licensee BioMed Central Ltd.

【 图 表 】

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