Abnormal preimplantation embryonic development Repeated implantation failure 2021-04-07T11:40:41Z Recurrent implantation failure Repeated implantation failure refers to a situation in which embryos of good quality fail to implant following several in vitro fertilization (IVF) treatment cycles. Successful embryo implantation is a process which requires both a synchronous development and interaction between hatched blastocyst and endometrium. From the clinical point of view, implantation is considered to be successful when gestational sac is diagnosed by ultrasound.