Embryo wastage rates remain high in assisted reproductive technology (ART): a look at the trends from 2004-2013 in the USA

This work examined the trend in "embryo wastage" rates after ART in USA and its relationship to the number of embryos transferred, live born infants delivered across patient age, and the yearly percentage of embryos wasted. The data were obtained from the US-clinics SART databank for the years 2004-2013. A total of 1,808,082 non-donor embryos were transferred in 748,394 fresh cycles resulting in 358,214 liveborn. During the years of analysis, the mean number of embryos transferred has progressively decreased leading to an overall significant decrease in Embryo Wastage rates (83.2 to 76.5%, p < 0.001) while the percentage of transfers leading to a live born increased (24.8 to 27.8%, p = 0.002). Embryo Wastage negatively correlated with percentage of transfers resulting in live birth (p = 0.001), and the average number of embryos transferred positively correlated with the percentage of embryos wasted (p < 0.001). The overwhelming majority of embryos transferred still do not result into a live birth confirming that only few embryos per ART cycle are competent. The overall "Embryo Wastage" rates have consistently decreased from a high of 90% in 1995 to a rate of 76.5% in 2013. Transferring fewer embryos particularly at the blastocyst-stage and improved methods of embryo selection may further decrease "Embryo Wastage" rates.