A frozen embryo transfer, or FET, is a kind of IVF treatment where a cryopreserved embryo created in a full IVF cycle is thawed and transferred to a woman’s uterus. The cryopreserved embryo may be from a woman’s previous conventional IVF cycle, or it may be a donor embryo. If a donor embryo is being used, the embryo is not genetically related to the woman or her partner.
Most of the time, a frozen embryo transfer takes place when there are “extra” embryos after a conventional IVF cycle. A “fresh” transfer is usually preferred. However, some doctors are recommending elective frozen embryo transfer—also referred to as a “freeze all” approach—where afresh transfer is not attempted. In this case, all embryos are cryopreserved and transferred in a FET cycle in the next month or so.