Taking IVF to the next level –a time-lapse story
Inge Errebo Agerholm
Laboratory Director at the IVF clinic Horsens, Denmark
Abstract
Today the selection of the most competent embryos is still mainly based on morphology evaluation. In most laboratories the evaluation includes the degree of fragmentation, presence and number of nuclei and size, number and symmetry of blastomeres at discrete assessment points. However, the challenge to identify the single embryo with highest developmental competence has become more important with the introduction of eSET and several areas are being investigated in search of additional markers of viability to supplement current criteria for selection, e.g. aneuploidy screening, O2 respiration, metabolic profiling and gene expression analysis.
Nevertheless, more frequent evaluation is necessary for a more precise morphological assessment. However, the present laboratory set-up implicates a risk for the embryos since they are exposed to changes in temperature, humidity and gas composition when evaluated. A conflict between the need to achieve a detailed picture of the timing and dynamics of the embryo and the risk of compromising stable culture conditions therefore exists. With the introduction of time-lapse equipment approved for use on human embryos, continuous evaluation of embryo development seems to overcome the restrictions of discontinuous observation and several publications has already described the benefits of this culture method.
The lecture will focus on the potential of clinical use of time-lapse for continuous embryo assessment and discusses some of the new candidate dynamic parameters that have been identified in retrospective studies.