Quality control and standardization of embryo morphology scoring and viability markers

Abstract

A so-called 'good-quality embryo' may be defined as an embryo that has the potential to implant into the uterine endometrium and give rise to the birth of a healthy child. A standardized and objective scoring of embryo 'quality' is therefore crucial in the classification and selection of embryos. However, embryo scoring is still being performed mainly via ocular evaluation, which often results in different interpretations of embryo quality. The addition of viability markers, such as measuring gene expression or the uptake/release of metabolites, proteins or RNA/DNA molecules in the culture media, would increase the possibility of standardized measurements. However, no single biomarker has yet been introduced into standard clinical practice, mainly due to the complexity of the techniques and the influence of biological variations and differences in culture conditions. In this paper different methods for the scoring of embryos and the possibility of standardizing and implementing quality control systems are discussed.

Combined effects of individual culture and atmospheric oxygen on preimplantation mouse embryos in vitro

“…Cleavage times were defined as the first time point when new blastomeres were separated by cell membranes. To date, numerous systems for notation of cleavage events have been used, and while there have been proposals for standardization (Ciray et al, 2014;Kaser and Racowsky, 2014), there is still no consensus within the field (Lundin and Ahlstrom, 2015). Ths study has used a common notation system based on that used by Meseguer and colleagues (Meseguer et al, 2011): cleavage time to two cells is represented as t2, and so on for three to eight cells.…”

Prediction of blastocyst development and implantation potential <i>in utero</i> based on the third cleavage and compaction times in mouse pre-implantation embryos

“…Human in vitro fertilization-embryo transfer (IVF-ET) techniques are continuously being improved to increase implantation and pregnancy rates with better selection of transfer-competent embryos [3, 4]. Several studies have focused on identifying independent and useful predictors that can be used to select high-quality embryos in IVF laboratories [3,4,5,6,7,8,9,10]. A monitoring system to observe morphology during the course of in vitro pre-implantation embryonic development has been proposed [5,6,7,8,9,10,11].…”

Utilización de marcadores bioquímicos como método no invasivo en la determinación de la viabilidad embrionaria en Fertilización In-Vitro

“…Revista Ciencia & Salud: Integrando Conocimientos / Octubre -Noviembre 2019 / Volumen 3 / Número 5 metabolismo de carbohidratos y el turnover de aminoácidos, donde el alto consumo de piruvato y glucosa, así como el consumo de leucina y secreción de alalina, se han relacionado con mejor viabilidad del embrión y desarrollo de blastocitos de mejor calidad respectivamente. El fragmento soluble del HLA-G tiene importancia a nivel de la implantación del embrión y tolerancia del feto por parte de la madre (Sallam et al, 2016) (Lundin & Ahlstrom, 2015).…”

“…Se utiliza cromatografía líquida de alta eficacia (HPLC) para la determinación del turn over en aminoácidos y espectroscopía de infrarrojo cercano (NIR) que permite establecer perfiles metabolómicos para cada embrión (Vergouw et al, 2008), también mediante espectrometría de masas (Kovács et al, 2016), ELISA, el cual permite la determinación de antígenos como HLA-G (Lundin & Ahlstrom, 2015), analizadores de termoquimioluminiscencia y electroquímica para la medición del estrés oxidativo (Sallam et al, 2016).…”

“…La determinación del metaboloma presenta resultados confiables, estandarizados y requiere poca muestra (Lundin & Ahlstrom, 2015). No obstante, la medición de metabolitos puede resultar dificultoso por su complejidad química y heterogeneidad, por limitaciones intrínsecas de cada técnica y la falta de estandarización de los métodos (Lundin & Ahlstrom, 2015).…”