Methods for assessing the quality of mammalian embryos: How far we are from the gold standard?

Author(s)

Rocha, Jose C. ; Passalia, Felipe ; Matos, Felipe D. ; Maserati, Jr., Marc P. ; Alves, Mayra F. ; de Almeida, Tamie G. ; Cardoso, Bruna L. ; Basso, Andrea C. ; Nogueira, Marcelo F. G.

• Document type: Review article
• Source: JORNAL BRASILEIRO DE REPRODUCAO ASSISTIDA; v. 20, n. 3, p. 150-158, JUL-SEP 2016.
• Web of Science Citations: 6

Abstract

Morphological embryo classification is of great importance for many laboratory techniques, from basic research to the ones applied to assisted reproductive technology. However, the standard classification method for both human and cattle embryos, is based on quality parameters that reflect the overall morphological quality of the embryo in cattle, or the quality of the individual embryonic structures, more relevant in human embryo classification. This assessment method is biased by the subjectivity of the evaluator and even though several guidelines exist to standardize the classification, it is not a method capable of giving reliable and trustworthy results. Latest approaches for the improvement of quality assessment include the use of data from cellular metabolism, a new morphological grading system, development kinetics and cleavage symmetry, embryo cell biopsy followed by pre-implantation genetic diagnosis, zona pellucida birefringence, ion release by the embryo cells and so forth. Nowadays there exists a great need for evaluation methods that are practical and non-invasive while being accurate and objective. A method along these lines would be of great importance to embryo evaluation by embryologists, clinicians and other professionals who work with assisted reproductive technology. Several techniques shows promising results in this sense, one being the use of digital images of the embryo as basis for features extraction and classification by means of artificial intelligence techniques (as genetic algorithms and artificial neural networks). This process has the potential to become an accurate and objective standard for embryo quality assessment. (AU)

• FAPESP's process: 12/50533-2 - GIFT: genomic improvement of fertilization traits in Danish and Brazilian cattle
• Grantee: Marcelo Fábio Gouveia Nogueira
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 12/20110-2 - Software based on Artificial Neural Networks for embryo morphologic evaluation
• Grantee: Felipe Delestro Matos
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 06/06491-2 - Embryonic chimerism on murine and bovine species: Pattern of interaction between inner cell mass - from embryos produced in vivo - and recipient embryos produced in vitro
• Grantee: Marcelo Fábio Gouveia Nogueira
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 11/06179-7 - Use of Artificial Neural Network based system to evaluate viability and quality of mouse embryos
• Grantee: Felipe Delestro Matos
• Support Opportunities: Scholarships in Brazil - Scientific Initiation