How often does late implantation occur in ivf?

IVF implantation: After transfer of the embryo implantation occurs about 6-10 days later. There will always be some degree of human variation and the exact timing of implantation can not be predicted ahead of time. There is a physiologic window for implantation to occur by the nature of our physiology. Exactly how long that window is in any one individual during any one cycle is not known.