Frozen Embryo Replacement (F.E.R.) as a Treatment in Infertility

Management of a FER Treatment Cycle

The frozen embryo replacement cycle is relatively non-invasive compared to an egg collection cycle. The embryos can be replaced either in a natural cycle or in a controlled cycle depending on whether we can easily monitor the time of natural ovulation.

In a controlled cycle a Prostap injection (or Synarel nasal spray) and Progynova (oestrogen) tablets are administered in order to prepare the endometrium for implantation as an alternative to the natural changes occurring in the endometrium in a spontaneous ovulatory cycle.

The development of endometrium is monitored by ultrasound scanning (approximately 4 scans). Either when ovulation has occurred, or when the endometrium is thick enough, your embryos can be thawed for replacement.

Consent to Thawing

Before the laboratory can thaw any of your embryos, both partners must sign the Consent form for embryo thawing in the presence of one of our medical staff.

Thawing Your Embryos

The laboratory will thaw your embryos so that the stage of the embryos corresponds to your replacement cycle. The exact timing will depend upon the stage at which the embryos were frozen.

Not all embryos survive the freezing, storage and thawing process. On the morning of your embryo transfer, the laboratory will assess your embryos to see if they are suitable for transfer. If they are, then the embryo transfer can proceed.

The Embryo Transfer

For this procedure, a fine tube (catheter) is passed through the cervix and the embryos are injected high into the uterus in a minute amount of culture medium. This technique does not normally require sedation and is usually pain-free. The transfer will be made easier if you have a full bladder when you attend for this procedure.

After the Embryo Transfer

You will be given pessaries of a hormone called progesterone to support the lining of the uterus and 12 days after your embryo transfer a blood test (BhCG) is carried out in order to determine whether there is the earliest evidence of pregnancy.

Professor Craft is one of leading Infertility specialists in the world and his team has been freezing embryos since 1986 which has resulted in the birth of many healthy babies.