Preimplantation genetic testing for embryo aneuploidy: opportunities, problems, and prospects

DOI

https://dx.doi.org/10.18565/aig.2021.11.42-49

Savostina G.V., Perminova S.G., Ekimov A.N., Veyukova M.A.
Academician V.I. Kulakov National Medical Research Center of Obstetrics, Gynecology, and Perinatology, Ministry of Health of the Russian Federation, Moscow, Russia

Human embryo aneuploidies make a substantial contribution to the etiology of implantation failures and early reproductive losses in assisted reproductive technology (ART) programs. The currently available methods for the morphological assessment of embryo quality cannot rule out aneuploid embryo transfer into the uterine cavity. The most common method for assessing the ploidy of an embryo is preimplantation genetic testing for aneuploidy (PGT-A). The introduction of PGT-A into clinical practice could considerably reduce the likelihood of aneuploid embryo transfer into the uterine cavity and enhance the effectiveness of ART programs. However, the expediency of using PGT-A in various groups of patients at high risk for aneuploid embryo formation, as well as in married couples with a good prognosis requires discussion. The paper gives a detailed analysis of the literature data from the studies evaluating the effectiveness of using PGT-A for embryos in patients of older reproductive age, in those with recurrent implantation failures or recurrent miscarriage, as well as in couples in whom the male partner had severe spermatogenic failure. The paper discusses the expediency of routine use of PGT-A in married couples with a good prognosis, as well as when using donor oocytes. It presents the stages of PGT-A, advantages and disadvantages of various methods of PGT-A and material sampling methods for analysis, as well as the possible reasons for of false positive and false negative results of PGT-A.
Conclusion: PGT-A is a modern high-hrly informative method for assessing the chromosomal status of an embryo before its transfer in the ART programs. Currently, the most common method of PGT-A is high-throughput next-generation sequencing (NGS), whereas trophectoderm biopsy is a procedure to obtain material.

preimplantation genetic testing

embryo aneuploidies

recurrent miscarriage

older reproductive age

recurrent ART failures

Full text (in Russian)

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Received 31.05.2021

Accepted 02.09.2021

Guzel V. Savostina, graduate student, Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology,
Ministry of Health of the Russian Federation, +7(925)633-35-16, savostina2324@gmail.com, 117997, Russia, Moscow, Ac. Oparin str., 4.
Svetlana G. Perminova, MD, PhD, Leading Researcher of Reproductology Department, Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology, Ministry of Health of the Russian Federation, perisvet@list.ru, 117997, Russia, Moscow, Ac. Oparin str., 4.
Alexey N. Ekimov, doctor-laboratory geneticist, Head of the Group of preimplantation genetic screening of the Laboratory of Molecular Genetic Methods,
Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology, Ministry of Health of the Russian Federation,
a_ekimov@oparina4.ru, 117997, Russia, Moscow, Ac. Oparin str., 4.
Maria A. Veyukova, MD, PhD, Leading Embriologist of Reproductology Department, Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology, Ministry of Health of the Russian Federation, veymary@gmail.com 117997, Russia, Moscow, Ac. Oparin str., 4.

Authors’ contributions: Savostina G.V. – literature search and analysis; processing of the source material, writing the text of the manuscript; Perminova S.G., Ekimov A.N., Veyukova M.A. – editing the manuscript and its final approval.
Conflicts of interest: The authors declare that there are no conflicts of interest.
Funding: The paper has been prepared without sponsorship.
For citation: Savostina G.V., Perminova S.G., Ekimov A.N., Veyukova M.A. Preimplantation genetic testing for embryo aneuploidy: opportunities, problems, and prospects.
Akusherstvo i Ginekologiya/Obstetrics and Gynecology. 2021; 11: 42-49 (in Russian)
https://dx.doi.org/10.18565/aig.2021.11.42-49

Preimplantation genetic testing for embryo aneuploidy: opportunities, problems, and prospects

Savostina G.V., Perminova S.G., Ekimov A.N., Veyukova M.A.

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