Frozen Embryo Transfer (FET)
Understanding Frozen Embryo Transfer (FET)
Frozen embryo transfer (FET) is very simple compared to a fresh IVF cycle. Because the egg or eggs have already been retrieved to create the frozen embryo, it does not involve ovarian stimulation, egg collection or fertilization. Once the woman is ready to start the process of frozen embryo transfer, she takes hormones to prepare her uterus to receive the embryo. This hormone preparation usually takes between three and four weeks. The embryo transfer is performed under ultrasound guidance and there is no need for anesthesia.
For whom is FET the right choice?
In fact, there is a growing belief that under certain conditions, all embryos in an IVF cycle should be frozen and transferred later.
FET is an excellent option for people for several reasons:
- If the fresh cycle doesn't go well, there’s always the option of thawing and using the frozen embryos again.
- Couples who aren't ready to start or expand their families but are worried about losing their future fertility.
- Couples that have just had a successful IVF cycle and want to be able to have future pregnancies without having to go through the IVF cycle all over again.
How successful is FET?
Frozen embryo transfer has been performed for many years and has resulted in the successful birth of several thousand healthy babies. There is no data to suggest an increased risk of abnormalities due to the freezing and thawing process.
The development of the Vitrification technology, which helps to prevent the formation of ice crystals within the embryo, has significantly improved the survival rate of embryos during the thawing process. Approximately 80 percent of fresh embryos survive the freeze-thaw process if vitrification is used.
Recent studies suggest that if you directly compare top quality fresh and frozen, the frozen embryos may in fact yield a better pregnancy outcome, along with a lower chance of obstetric complications such as preterm labor and fetal growth restriction.
We're happy to say that around 40% of our frozen embryo transfers result in a pregnancy. About 20 percent of all children born from IVF cycles worldwide are from embryo cryopreservation and frozen embryo transfer procedures.