P-222 Can embryo morphokinetics act as early warning key performance indicators in relation to consumable batching

Abstract Study question Can morphokinetics be used as an early warning indicator of a batch-related effect of oil currently in use in the laboratory on implantation rate? Summary answer Where morphokinetic timings were slower for a batch of oil, implantation rate was also reduced, suggesting they could be used as an early warning system. What is known already The commercialisation of oil means that there are strict manufacturing guidelines leading to consistency between batches. However, this does not mean that minor differences do not exist. Furthermore, oil can undergo peroxidation if stored incorrectly, causing it to become toxic to embryos. The introduction of timelapse incubation has allowed extensive research into several morphokinetic parameters. This research has established time-frames within which each developmental milestone should occur to indicate the likelihood of implantation. Implantation rate (IR) is often used as a key performance indicator in the laboratory however, potential systemic issues may be identified sooner if morphokinetic parameters were used. Study design, size, duration The following morphokinetic parameters were compared to IR to determine if a batch of oil was affecting embryo development; time of division to two cells (t2), five cells (t5), eight cells (t8), time to start of blastulation (tSB) and cell synchronicity between two and eight cells (CS2-8). Data from January 2019 to October 2019 from a single centre were used, and included data from 2008 embryos and 333 patients. Participants/materials, setting, methods Data was exported from the EmbryoScope + [Vitrolife, Sweden]. Data from RIWitness Laboratory Manager [CooperSurgical, Denmark] was utilised to identify when different batches of oil (Ovoil™, Vitrolife) were used within the specified time period. The data from the EmbryoScope+ was then separated by date to signify when a new batch of oil was open. A Kruskal-Wallis test was then used to identify whether the morphokinetic timings differed between batches of oil. Main results and the role of chance There was no significant difference in patient age (p = 0.178) or the number of oocytes collected (p = 0.097) between batches of oil used. There was no significant difference between the morphokinetic timings for each batch of oil used. However, the morphokinetic timings follow the same trend line as the IR for both t2 and t8; where t2 and t8 are higher, the IR for the corresponding batch of oil is reduced. The trend can also be seen in CS2-8. The batch of oil with the lowest IR (25.56%) also had the highest mean time to t2, t8 and tSB compared to the other batches of oil. This corresponds with previous research that identified a correlation between slower embryo development and reduced IR (Meseguer et al., 2011). A clear difference could be seen between the average time taken to reach each developmental milestone and each batch of oil used, perhaps suggesting oil can have an effect, however small, on embryo development. This study suggests that morphokinetic timings could be used as an early warning indicator that a new batch of oil may be affecting development allowing a rapid response by the laboratory team and possible cessation of use pending further investigation. Limitations, reasons for caution Different batches of culture medium were also used throughout this time period and were not introduced at the same time as oil batches. Therefore, the results of this investigation cannot be associated entirely to the introduction of a different batch of oil. Wider implications of the findings This information could be incorporated into an early warning algorithm that could be assessed after a batch of oil was introduced. The use of the batch could then be ceased immediately without waiting for a decrease in IR by which time it would have been used for many more embryos. Trial registration number Not applicable