Following IVF or ICSI treatment, there may be healthy extra embryos that are not transferred. These are suitable for the future use of the patient if required eg. patients want more children. These extra embryos can be frozen, stored in liquid nitrogen, and thawed and transferred to the mother’s uterus when desired. The process is called Frozen Embryo Transfer or FET.
Following ICSI treatment and Preimplantation Genetic Testing (PGT) such as Next Generation Sequencing (NGS), embryos must be frozen pending genetic testing results. After results are completed, abnormal embryos can be discarded, and the healthy embryos remain stored in liquid nitrogen, and are thawed and transferred to the mother’s uterus when desired. The process is also called Frozen Embryo Transfer or FET.