A frozen embryo transfer is where an embryo that was frozen in a previous IVF cycle is carefully thawed before being transferred into the womb.
Want to know if this is for you? You can talk to one of our fertility experts.
A frozen embryo transfer (FET) is a fertility treatment where frozen embryos, from a previous IVF cycle, are placed in the womb with the hope of becoming pregnant.
This gives you another opportunity to become pregnant without having to start from the beginning of a new IVF cycle.
The transfer may take place during a natural cycle or a hormone-regulated cycle.
A hormone-regulated cycle involves you taking medication to temporarily switch off your ovaries and thicken the lining of your womb.
A frozen embryo transfer in a hormone-regulated cycle takes around four weeks.
A frozen embryo transfer may be a fertility option for you if:
Although freezing your embryos doesn’t guarantee a future pregnancy, it gives you the option of trying fertility treatment when you’re ready.
We offer frozen embryo transfer to couples and single women who have stored their frozen embryos with us, or those who wish to transfer their embryos to us from another clinic.
We can help organise relocating your frozen embryos to TFP Fertility to continue your treatment here.
If you’d like to know more about frozen embryo transfers at one of our clinics or would like to book an appointment, please get in touch. We’ll get back to you within 48 hours and provide you with all the information you need to get started.
The cost of frozen embryo transfer at TFP Fertility UK varies because we carefully tailor each individual treatment plan to give the best chance of success.
A typical FET cycle includes:
monitoring scans
embryo thawing
post-thaw culture
embryo transfer
early pregnancy scan
You can find a detailed price list for all treatments and procedures on each TFP Fertility clinic page.
Find your nearest clinic, or use our contact form to request a confidential chat about your circumstances, whether frozen embryo transfer is right for you, and to take you through the costs.
The embryo is carefully warmed to thaw it safely, and we sometimes grow an embryo for a day or so after thawing to see if it will develop further.
The embryo is then returned to an incubator, ready for transfer to the womb.
Having a multiple pregnancy (twins, triplets, or more) is the greatest health risk associated with fertility treatment.
For this reason, we typically thaw one embryo first and then assess its quality.
Not all embryos survive the thawing process.
If this is the case, you will be offered a follow-up appointment with one of our consultants to discuss the results and further options, which may include thawing another embryo.
We freeze embryos instantly in liquid nitrogen, using a technique called vitrification.
Vitrification freezes day 5 to 6 embryos. This process means more embryos survive with better outcomes compared to older freezing techniques used for day 2 to 3 embryos.
Due to vitrification, the embryos are safely held in a suspended state during their time in storage, with no age-related deterioration.
Frozen embryos can be transferred into the womb during a natural cycle or a hormone-regulated cycle. Both are equally effective.
If you have a regular menstrual cycle we would encourage a replacement as there are medical benefits in pregnancy such as the lowering of blood pressure and pre eclampsia risk.
But it’s important to note that the timings of events in a natural cycle are outside anyone’s control.
There may be occasions where the cycle is delayed either because no follicle develops or a mid cycle surge is missed or does not occur.
At TFP Fertility, treatment will be available at weekends and on bank holidays. This means that even if an embryo replacement is needed on a Saturday or Sunday, we will replace an embryo.
If you’re keen to discuss your fertility treatment options, have a question about frozen embryo transfer, or would like to book an appointment at your local TFP Fertility clinic, please use our contact form. There’s no experience like this, and we’re here with you every step of the way.
A typical frozen embryo transfer will follow one of two regimens dependant on your past medical history, cycle lengths and prior fertility history.
The first step of the FET process is to have a review appointment, if this is immediately after an unsuccessful cycle or one where we have frozen all the embryos, the time to your transfer will be shorter.
If a significant amount of time has passed, for example after a successful pregnancy, further tests may be needed such as a detailed pelvic scan to assess the uterine anatomy and endometrial thickness.
During the consultation, we'll discuss your medical history and assess your menstrual cycle to settle on a treatment plan. We will also decide on an FET in a natural or hormone-regulated cycle.
Both options have their benefits and risks. These will be discussed with you as part of the decision-making process.
A natural cycle requires no medication, it is ideal for if you:
Have regular monthly cycles
Experience of a “mid-cycle ovulation surge”
Have evidence that subsequent pregnancies will have a lower risk of hypertension (high blood pressure) and pre-eclampsia
This maybe because the corpus luteum (where you have ovulated from) produces growth factors and hormones that may be beneficial to the establishment of a healthy pregnancy.
Some people will opt to have additional luteal hormonal support after an embryo transfer, and this can be discussed with your doctor.
In approximately 10% of cases no ovulation will be detected, or follicle develop.
If this is the case, we'll move to a medicated/hormonally controlled cycle the following month.
In a natural cycle we'll arrange for:
Your consent forms are signed in advance
You're taking preconceptual vitamins
And, if using luteal support, to have this on prescription
Progesterone luteal support is usually in the form of vaginal pessaries or tablets.
In some cases, subcutaneous or intramuscular injections can be used dependant on your individual history.
Once you are booked in for treatment, a scan will be arranged on around day eight of your menstrual cycle to assess endometrial thickness, and to see if a follicle is developing.
If all looks good this may be the only scan that is needed.
Once the endometrium has reached a certain thickness and there is a dominant follicle, you'll be asked to do morning and evening urine ovulation tests.
After detecting a midcycle surge on dipstick you will be asked to contact the unit and a pan will be made to coordinate your embryo transfer five to six days later.
This type of cycle is ideal if you:
Have irregular monthly cycles
Find ovulation has been difficult to predict or record
If you have PCOS, you may be advised down this route or if there has been a problem with thickening the lining of the womb in a natural or fresh IVF cycle.
The process requires that you take oral oestrogen tablets or transdermal oestrogen patches and have a course of injections between days two and six of your cycle to suppress your own ovulation.
We'll organise a scan to assess the endometrial thickness around day 14 and if thick enough, will add in progesterone luteal support.
The embryo transfer will be coordinated on the sixth day of progesterone.
Progesterone luteal support is usually in the form of vaginal pessaries or tablets.
In some cases, subcutaneous or intramuscular injections can be used dependant on your history.
In a medicated cycle we'll organise that:
Your consent forms are signed in advance
You're taking preconceptual vitamins
And, if using luteal support, to have this on prescription
Ideally, we would ask that you book in the month preceding treatment so as to be able to make sure that all steps are in place, you're happy injecting the medication and your prescription is delivered.
On the day of the embryo transfer you'll be asked to attend at a set time with a full bladder.
The embryology team will have checked your consents and will have thawed a frozen embryo or embryos, dependant on your medical history and embryo quality.
Embryos frozen at the blastocyst stage (day five or six) have approximately 95% chance of surviving the freeze thaw process.
If your embryo doesn't survive and there are additional embryos in store, we will thaw a further embryo.
The embryology team will assess the embryos and how they have done through the freeze thaw process by looking at the expansion of the blastocyst and how many cells have survived both in the inner cell mass and trophectoderm.
These are the two specific cell types of the blastocyst:
The inner cell mass forms the baby
The trophectoderm cells form the placenta
Blastocysts are collapsed when frozen as part of the vitrification (freezing) process and as part of the thaw will start to re-expand.
The embryo transfer will be carried out by an experienced member of the team either a doctor or nurse. It's done under ultrasound guidance.
A speculum is passed into the vagina, the embryos are loaded by the embryologist into a soft transfer catheter in a small amount of media (fluid) in the laboratory.
The catheter is brought into the theatre where it is then passed through the cervix into the uterine cavity. The process takes usually less than five minutes.
You can go to the lavatory immediately and do not need to lie down and rest. Your partner will be able to come into theatre with you for support.
If sedation is required for embryo transfer this can be arranged and embryo transfer will proceed in theatre.
Your partner will not be able to accompany you in this setting.
After your embryo transfer, we’ll give you the best date to carry out a pregnancy test, which will be around two weeks after the procedure.
We do understand what an intense and difficult wait this can be.
But, however tempting, we advise not testing before then, as the results could be misleading.
During this anxious time, do call us if you have any questions or concerns.
We’re with you and ready to give you reassurance and encouragement to get you through this time.
We also offer a range of supporting therapies, such as reflexology and acupuncture, which can relieve stress and help you feel better, both physically and emotionally.
You can book these at any point in your fertility journey with us.