0208 0758881

Frozen Embryo Transfer (FET)

FET – Frozen Embryo Transfer

FET Frozen Embryo Tranplant 

This article has been submitted by Sareena Sharma, Embryologist at specialist fertility clinic, IVF London.

What is FET?

Whether you are undergoing fertility treatment or have had your eggs or embryos frozen, you will have heard of the term ‘FET’ or Frozen Embryo Transfer. The procedure is normally done in an unstimulated cycle and consists of careful monitoring and preparation of the lining of the uterus.

A lot of the times after a cycle of IVF or ICSI, you’ll find that there will be a number of successfully fertilised embryos that can be frozen and stored for your future use. Regardless of your cycles success a frozen embryo transfer can offer you another chance of pregnancy from the initial egg collection without having to go through an egg collection again. A frozen embryo transfer can be done in a totally ‘natural’ cycle or in a medicated cycle. For a natural cycle it is important to have a regular menstrual cycle.

What happens during an FET cycle?

There are four stage to an FET cycle: the initial scan & consultation; the nurse consultation; the monitoring phase; the embryo transfer.

During the initial scan and consultation, you will meet with a fertility specialist/consultant who will conduct an assessment of your case and will create a personalised treatment plan, geared towards giving you the best chance at a successful outcome.

Two weeks before the start of your menstrual cycle you will come at the clinic and attend your nurse consultation. It is here that you will go with the nurse through your personalised treatment plan to ensure that you fully understand the process and the next steps of your journey. It is also at this step that you will then go through the relevant consent form that will have to be completed. All the medications involved will be explained.

The next step after the nurse consultation is the monitoring phase. During this step you will have to undergo two to three monitoring scans, with each taking around 15-20 minutes to complete; the first scan is a baseline scan which is done after you have your period and the other two scans are done after you take 7-10 days of medications to prepare your womb to receive the embryos. Sometimes blood tests may be necessary during this phase. Once the lining of your womb has been checked and reached the desired thickness further hormonal support in the form of progesterone will be given. An embryo transfer date is then set.

The last stage comprises of the embryo transfer, the procedure itself is quite, taking between 20 – 30 minutes. Generally, the procedure does not necessitate sedation, but it is important to note that in certain cases where access in to the uterine cavity can be difficult, sedation may be required.

Why should you have an FET cycle?

There are a few other things that have to be kept in mind when deciding on doing an FET cycle.

Firstly, your embryos will not deteriorate over time whilst they are kept in storage. In fact, the frozen embryos will be kept in a state of suspended animation, which stops any deterioration from occurring. This is achieved by dehydrating the cells of the embryos by removing the water content and storing the embryos in liquid nitrogen at a temperature of -196 Celsius.

Secondly, the success rates. Initially it was believed that fresh embryos would offer a better success rate compared to using frozen embryos, but the success rate has increased significantly every year due to the relentless work of fertility researchers and embryologists around the world. It is important to note that the success rates are strongly linked to the age of the patient and embryo quality. Below you will find a graph that will give you a general understanding of FET success rates with frozen embryos compared to fresh ones. This graph has been derived from the fertility regulator’s website: the HFEA. It is important to understand that the results are based on livebirth rates and is per embryo transferred.

Birth rate embryo transfer

For Further information feel free to book a consultation with our Fertility Consultants through the online form, on 020 8207 4115 or email [email protected]


Leave a Reply

Frozen Embryo Transfer (FET)

Monitored placement of your
thawed embryos into the uterus
to achieve pregnancy

Introduction - Frozen Embryo Transfer

If you have undertaken a previous IVF cycle of medication, egg collection and fertilization of embryos for transfer, you will have been advised of the availability of any additional good quality embryos that you may have requested be frozen in preparation for any subsequent treatment.  Your embryos will be cryopreserved (frozen) and stored on site at our clinic.

Our laboratory uses the highly successful technique of Vitrification to freeze the embryos and hence the survival rates of embryos are in excess of 95%.  The pregnancy rates from Vitrified (frozen) embryos is as good as fresh transfers if they survive the thawing.

Why Choose Frozen Embryo Transfer (FET)?

If a previous IVF cycle was not successful, you suffered from OHSS within a cycle or you now wish to add a sibling to your family, IVF London can prepare you for a frozen embryo transfer using your stored embryos.

IVF treatment using FET is also recommended where your fertility may be at risk owing to your reproductive organs likely being damaged during cancer treatments by allowing you to preserve your fertility prior to commencement of any such treatment.

How Does Frozen Embryo Transfer (FET) Process Work?

You won’t need to undergo further ovarian stimulation or a full IVF cycle again as we will already have your embryos on site from your previous cycle. These embryos will be thawed and assessed to check their suitability before they can be placed back into your uterus as with your previous IVF embryo transfer.

Natural Cycle Replacement (NC FET)

NC FET is conducted when a woman has regular ovulation and menstrual cycles. Your cycle will be monitored to determine the precise timing of ovulation or alternatively, you may need to have an HCG injection to stimulate a more exact ovulation period. At this time we will schedule your embryo transfer by defrosting and preparing your embryos to coincide with the approximate time they would usually be arriving in your uterus. This ensures that your endometrium (the lining of the womb) is at its most receptive for a successful implantation.

Medicated Protocol for Endometrial Preparation

A medicated FET cycle is used when we need to more closely control the preparation of your endometrial lining so that it will be at its most receptive for embryo transfer.  In this type of FET, you will undertake a cycle of estrogen pills to help thicken the lining of the womb. Just prior to transfer, you will also be required to take progesterone to help modify the lining so that it is receptive when the embryos are transferred.

What Happens Next: Embryo Freezing as Part of Your Fertility Journey

Once the embryos have been transferred into your uterus, you will be need to continue taking any drugs prescribed in your treatment and wait 16 days before taking a pregnancy test to see if your treatment has been successful. You can continue your day to day activities but we recommend you refrain from any strenuous physical exercise and rest if you feel you need to. The clinic will confirm your pregnancy with ultrasound scans and blood tests before discharging you back to your own GP for antenatal care.

Risks and Considerations of Frozen Embryo Transfer (FET)

This risks of FET are similar to those outcomes of a traditional IVF cycle, including multiple births, ectopic pregnancies and miscarriage. Your consultant will discuss any risks that may be relevant to your individual history and circumstances and can answer any questions you may have. If at any time you are concerned, please do contact the clinic for advice. There is a very small risk that none of the frozen embryos may survive the freezing and thawing procedure in which case the cycle would need to be abandoned.

Why Choose Us?

Here are some facts about your fertility journey with us that we’d like to share with you:

Every evaluation and treatment plan is uniquely tailored to meet your individual needs

You will have access to leading professionals, with over 35 years combined expertise, providing you with confidence and reassurance in your fertility diagnosis and subsequent treatment

Our multidisciplinary team includes specialists in fertility, urology, nutrition, counselling, genetics, endocrinology, haematology and weight management to provide a comprehensive range of support as and when you need it

We will work with you closely to understand your individual circumstances, identify any problems and agree with you, the best course of action to help make your dream a reality

We will always be honest and open about your chances of success with treatment.

Your comfort and care is always our top priority

Our focus remains entirely on you as an individual, your unique needs and your wellbeing

All investigations and treatments are provided within our new state-of-the-art clinic based in Elstree which offers a spacious environment with comfortable surroundings, to enhance your care and experience. We offer investigations and scans at our satellite locations too.

Our friendly consultant-led team is here to support you at every step throughout your fertility journey

Book A Free Mini Consultation
Call Now Button
Call Us