Patients who have extra embryos available after an in vitro fertilization (IVF) cycle can choose to freeze any extra embryos.  If a patient does choose to freeze (cryopreserve) embryos, they can be transferred into the uterus in a future cycle.  Embryos are typically frozen 3 days or 5 days (blastocyst) after fertilization.

If an IVF patient does not get pregnant with the “fresh” IVF cycle, or if she conceives and wishes to have another child following, the extra frozen embryos can be thawed and placed back into her uterus.  In a frozen embryo transfer (FET) cycle, she does not need to take any injectable stimulatory medications. The FET cycle is much less taxing compared to a “fresh” IVF cycle -- both physically and financially. The cost of an FET cycle is a fraction of the cost of a fresh IVF cycle and may be covered by insurance.

Patients meet with Dr. Andrew Levi before FET cycle to discuss whether additional testing should be performed before the frozen embryo transfer.  Dr. Andrew Levi will also discuss how many embryos should be transferred back.  Of note, some embryos may not survive the thaw process and multiple pregnancies may result from a frozen embryo transfer.

About 70-80% of high-quality embryos are expected to survive the thawing process.  An embryo is said to survive if at least half of its cells are alive.  For example, if a six-cell embryo is thawed, and three cells are alive, that embryo has survived the thaw.  If the desired number of embryos does not survive the thawing process, additional embryos can be thawed in time for the scheduled embryo transfer since embryos thaw fairly rapidly.
 
After the embryo transfer, patients rest for about twenty minutes in a recovery room. The restrictions following the embryo transfer are similar to that of a fresh embryo transfer.