Application of time-lapse technology in Assisted Reproductive Technology (ART) treatments
Romualdo Sciorio
Fertility Medicine and Gynaecological Endocrinology Unit, Department Woman Mother Child, Lausanne University Hospital, Lausanne, Switzerland
Abstract
During human in vitro culture, a morphological microscope analysis is normally performed to select the embryo with the highest implantation potential to replace, with the hope to obtain a successful pregnancy and health live birth. The morphological evaluation may combine number and size of blastomeres, fragmentation, multinucleation, blastocyst expansion, inner-cell mass and trophectoderm appearance. However, standard microscopy evaluation involves the removal of the embryos from the incubator, exposing them to un-physiologic conditions as changes in pH, temperature, and oxygen level. Additionally, morphological assessments might include high inter-observer variability. Recently, continuous embryo culture using time-lapse monitoring (TLM) has allowed embryologists to analyse the dynamic and morphokinetic events of embryo development and based on that, the embryologist is able to scrutinize the complete sequence of embryonic evolution, from fertilisation to the blastocyst formation. Therefore, TLM allows an uninterrupted culture condition, reducing the need to remove embryos from the incubator. The monitoring system is normally composed of a standard incubator with an integrated microscope coupled to a digital camera, which is able to collect images at regular times, and subsequently processed into video. These data can be annotated and analysed using an integrated software, thus allows embryologists to facilitate the process of embryo selection for transfer. The main aim of this paper is to discuss the potential benefits and uses of the TLM in the embryology laboratory.
Keywords: Time-lapse monitoring, medically assisted reproduction, embryo culture, morphokinetic evaluation, embryo viability