Frozen Embryo Transfer (FET) refers to the placement, after thaw, of previously frozen embryos into the uterus. The use of frozen embryos affords our patients a second or even third opportunity to achieve pregnancy without undergoing another round of ovarian stimulation and egg retrieval.
Embryos may remain frozen indefinitely, and are usually transferred during a cycle in which the uterine lining has been stimulated using both estrogen and progesterone. (Note: greater than 90% of embryos survive cryopreservation and the thawing process. Those embryos may implant and develop into ongoing pregnancies at a somewhat lower rate than do fresh embryos.)
A frozen embryo transfer, like many other IVF procedures involves multiple steps, each of which occurs at a specific time during the menstrual cycle.