Frozen Embryo Transfer (FET)

Management of the FET Treatment Cycle

You need to contact your specialist gynaecologist to organise a cycle plan to be sent to the Hubli Assisted Conception Centre for your FET cycle. They may require you to have an appointment with them to discuss this plan prior to commencing. You will also need to make a booking for an FET cycle, so please check with the Nurse Coordinator in advance. Please telephone the Hubli Assisted Conception Centre  approximately a fortnight before your cycle to arrange a time to sign consent forms, as we will not thaw any of your embryos without your written consent. One of these consents must be signed for each transfer cycle. It is also necessary for you to pay the appropriate prepayment before you begin your FET cycle.

The frozen embryo transfer cycle is relatively non-invasive compared to an oocyte retrieval 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. We aim to transfer the embryos into your uterus at the correct time in relation to ovulation and the thickness of the lining of your uterus (endometrium).

In a “natural” FET cycle (where no medications are used before the embryo transfer), the cycle is tracked for ovulation using blood tests to monitor the hormone levels. As ovulation draws near an ultrasound will be requested to measure the thickness and maturity of the endometrium. If this is suitable, the embryo transfer will be performed 2–3 days after ovulation.

In a “controlled” FET cycle, Progynova (oestrogen) tablets are administered in order to prepare the endometrium for implantation. The development of the endometrium is monitored by ultrasound scanning (approximately 1–2 scans). The first ultrasound is usually performed on day 10-12. When the endometrium is thick enough and of the right maturity, the embryos will be thawed for transfer. Progesterone pessaries are used in conjunction with Progynova to maintain the endometrium, and these medications may need to be continued often for the first trimester of a pregnancy.

Thawing your embryos

The embryologist will thaw your embryos so that the age of the embryos corresponds to the maturity of your uterine lining. The exact timing will depend upon the stage at which the embryos were frozen. You are asked to ring the day before your embryo transfer to check the time that the procedure is booked for. Not all embryos survive the freezing, storage and thawing process. You will be notified by the Nurse Coordinator/Specialist if there is a problem.

Embryo transfer procedure 

The embryo transfer procedure and follow-up tests are the same as for IVF embryo transfer, described previously.

The success rate of an FET Cycle

The success rate using frozen embryos is 20%. The pregnancy rate will depend on the number and quality of embryos transferred, your age and your cause of infertility.

If you decide you no longer wish to have your frozen embryos kept for yourselves you have the choice of donating them or disposing them. A combination of these choices is also available. If you have not used all your embryos after 12 months then you will be contracted to confirm your intentions. You will then be contacted every 6 months for reconfirmation of intentions, and an invoice will will also be sent for continuing storage at this time.