Frozen embryo transfer (FET)

What is frozen embryo transfer?

If you have undergone fertility treatment that has produced an embryo, such as IVF or ICSI, it is possible to freeze embryos not used in that cycle for later use.

How does a frozen embryo transfer work?

In a frozen embryo transfer (FET) cycle, we thaw your frozen embryos and transfer one or two of them into the uterus.

The Human Fertilisation and Embryology Authority’s (HFEA) guidance is that only two embryos may be transferred after a treatment cycle. Your doctor or embryologist will discuss the number of embryos to be thawed in any one attempt with you in advance.

If the treatment produced more than two (or three) good quality embryos, we can freeze those that aren’t used at extremely low temperature. This ensures that they do not deteriorate over the number of years they are stored for future use.

Benefits of frozen embryo transfer

An advantage of a FET cycle is that we do not need injections to stimulate the ovaries, instead you’ll be given medications to prepare your womb to receive these embryos.

During the procedure, we do an ultrasound scan to help us place the embryos where they have the highest chance of implantation.

The current pregnancy (live birth) rate for frozen embryo transfer is 17%. This compares favourably with the average national rate.

Risks of frozen embryo transfer

Although we are very selective about the embryos we freeze, only 90% survive after being thawed.