To determine in women undergoing IVF who are at high risk of multiple births (>35%), as calculated by the application of a predictive model - IVFsingleTM, if single embryo transfer will lead to both comparable clinical pregnancy rate (CPR) and other secondary outcomes such as live birth rate (LBR) and cumulative live birth rate (cLBR) in comparison to DET while reducing the incidence of multiple births (a secondary outcome measure).