The frozen embryo transfer (FET) process involves taking embryos which have been cryopreserved (frozen) previously and placing them into the uterus.
Frozen embryos remain viable for an infinite amount of time after the initial freeze. You may choose to do an FET cycle following an unsuccessful fresh IVF cycle or after a successful fresh IVF cycle if you’re ready to expand your family.
The success rates of an FET cycle are comparable to fresh IVF cycles—and sometimes result in an higher success rate because of the opportunity to optimize the lining of the uterus before implantation, among other reasons. Both fresh and frozen cycles have the same primary indicator for success: the maternal age at the time of embryo freezing. Many patients wait several years between the initially freeze of their embryos and attempting a subsequent FET cycle. Any patient, no matter the amount of time between embryo freezing and thawing, can expect nearly the same potential for success as they experienced with the fresh IVF cycle, which the frozen embryos came from. Women under 35 years have over a 60 percent chance of pregnancy per transfer. This rate declines as the maternal age at the time of the freeze increases.
In addition to the lower cost, benefits to a FET cycle include:
Instead of stimulation medication, patients use estrogen and progesterone to thicken the lining of their uterus in preparation for the embryo transfer to allow implantation. Since the stimulation phase was done in a prior cycle, there is also no egg retrieval requiring anaesthesia.
FET cycles are often less stressful than fresh cycles because factors like stimulation response, egg development, and embryo growth were considered during the fresh cycle. Yana IVF and Fertility Centre only freezes high quality blastocyst-stage embryos giving patients a significant chance of success with an FET cycle. Cycles are also more predictable with fewer cycle cancellations. Patients may select the day of their transfer months in advance, which will then be used to determine their cycle initiation date.