Time-lapse embryo monitoring: does it add to standard in-vitro fertilization/intra cytoplasmic sperm injection?

Since the first pioneering studies on time-lapse systems (TLSs) for embryo incubation, many things have changed. Two main factors influence the development of modern time-lapse incubators for human in-vitro fertilization (IVF): 1) the switch from traditional cell culture incubators to benchtops incubators, more suitable for human IVF; and 2) the improvement of imaging technology. Another major factor for the increase in the utilization of TLSs in IVF labs over the last decade was the advances in computer/wireless and smartphone/tablet technology, which allowed patients to see the footage of their growing embryos. Hence, more user-friendly features have allowed their introduction and routine use in IVF labs while image-capturing software has enabled storage and providing additional information to the patients concerning the development of their embryos. This review aims to describe the history and the different TLSs available in the market, to summarize the research and clinical results obtained by using this technology, and to reflect on how this technology is changing the modern IVF laboratory. The current limitations of TLSs will be also reviewed.