Recurrent Implantation Failure
Implantation is a stage of pregnancy in which the embryo attaches to the uterine wall. Successful embryo implantation occurs in a receptive uterus, and an ultrasound scan of the endometrium confirms the result.
Recurrent Implantation Failure (RIF) refers to the failure to achieve a viable pregnancy after transferring after the transfer of at least four good-quality embryos, with at least three fresh or frozen cycles in women under the age of 40 years.
Recent studies suggest that most RIFs occur due to embryo factors, and this can be lowered by transferring euploid embryos (embryo which has the normal number of 46 chromosomes).