Frozen Embryo Transfer (FET): What to Expect, Timelines, Success Rates & Testing After IVF
Frozen embryo transfer (FET) is a deliberate, evidence-led IVF strategy. It allows embryos created during IVF to be frozen, stored, and transferred in a later cycle when the body and timing are aligned. For many people, FET is the planned next step in modern IVF, offering flexibility, clinical control, and strong success rates.
Author
Tassia O’Callaghan
Reviewed by
Kayleigh Hartigan
27 min read
Spotlight:
- FET is a planned IVF strategy, where embryos created in a previous cycle are frozen, thawed, and transferred in a later, carefully timed cycle.
- Embryos are frozen using vitrification, a rapid freezing method with thaw survival rates above 90%, making freezing a routine and reliable part of modern IVF.
- Most frozen transfers use day-5 or day-6 blastocysts, which allows better embryo assessment and closer alignment with the uterine lining.
- Frozen transfers happen in a hormonally calmer cycle, which can reduce medical risks such as OHSS and support implantation for some people.
- FET supports flexibility and personalisation, including recovery time, genetic testing (PGT), and planning around health or life circumstances.
- In UK data, frozen transfers show higher pregnancy and live birth rates than fresh transfers, though outcomes always depend on individual factors like age and embryo quality.
What is a frozen embryo transfer (FET)?
A frozen embryo transfer (FET) is an IVF treatment where an embryo that has been created during a previous cycle is thawed and transferred into the uterus in a later menstrual cycle. The term “frozen” refers to the use of vitrification, an ultra-rapid freezing process that prevents ice crystal formation and protects the embryo’s structure. This method has transformed IVF outcomes, with most clinics now expecting thaw survival rates above 90% for vitrified embryos, based on UK and international data. [1]
Embryos can be frozen at different stages of development. Some are frozen on day 3, at an earlier stage, which may be appropriate when fewer embryos are available. More commonly, embryos are frozen at day 5 or day 6, once they have reached the blastocyst stage. Blastocysts are more developed, allowing clinicians to better assess embryo quality and align transfer timing with the uterine lining.
Frozen embryo transfer plays a central role in modern IVF because it gives clinics greater control over timing and treatment conditions. It allows embryos to be transferred in a more hormonally stable cycle, reduces the risk of ovarian hyperstimulation syndrome, supports genetic testing such as PGT, and separates egg collection from embryo transfer to allow physical or emotional recovery where needed. For these reasons, the HFEA recognises embryo freezing and frozen embryo transfer as routine and well-established parts of IVF treatment in the UK. [2]
IVF Step-by-Step: What to Expect at Each Stage
Learn more about IVF: the steps involved, how much it costs, understand success rates and risks – all in one convenient, in-depth guide.
Frozen vs fresh embryo transfer: What’s the difference?
The key difference lies in timing and hormonal environment.
With a fresh transfer, embryos are transferred a few days after egg collection, during the same stimulated cycle. With a frozen transfer, embryos are transferred in a later cycle, either natural or hormonally prepared.
While more fresh cycles are carried out in the UK compared to frozen embryo transfer cycles (~41,000 fresh cycles versus ~35,000 frozen cycles), clinics increasingly recommend frozen transfers because the uterus is not recovering from stimulation, hormone levels are more controlled, scheduling is more flexible, and medical risks are lower for some patients. [3]
Fresh transfer may still be used in straightforward cases with good response to stimulation and no medical concerns. The choice is clinical, not hierarchical.
| Aspect | Fresh embryo transfer | Frozen embryo transfer (FET) |
|---|---|---|
| Success rates | 24% birth rate 31% pregnancy rate | 32% birth rate 41% pregnancy rate |
| When the transfer happens | In the same cycle as egg collection, usually 3–5 days after retrieval | In a later IVF cycle, after embryos have been frozen and thawed |
| Hormonal environment | Occurs during a stimulated cycle with high hormone levels | Takes place in a natural or carefully controlled hormonal cycle |
| Embryo storage | Embryos are transferred immediately | Embryos are frozen using vitrification and stored until transfer |
| Cycle flexibility | Limited flexibility, tied closely to egg collection timing | Greater flexibility for scheduling and medical planning |
| Use with PGT testing | Not suitable, as results are not available in time | Commonly used after PGT-tested embryos |
| Risk of OHSS | Higher risk for people who respond strongly to stimulation | Lower risk if taking place during a natural or minimal hormonal cycle |
| Physical recovery before transfer | Minimal recovery time between retrieval and transfer | Allows full recovery before embryo transfer |
[3]
Are frozen embryo transfers more successful?
Looking at the latest data from the HFEA, frozen embryo transfers are more successful than fresh embryo transfers. Fresh embryo transfer is associated with around a 31% pregnancy rate and a 24% birth rate, while frozen embryo transfer shows higher outcomes, with around a 41% pregnancy rate and a 32% birth rate. These figures reflect population-level data and help explain why many clinics now favour frozen transfer as a first-line strategy. [3]
That said, success is never about one factor alone. Outcomes still depend on who is being treated, the quality and stage of the embryo, and how the transfer cycle is prepared. Frozen transfers often take place in a more hormonally stable environment, with time for recovery, which may support implantation and early pregnancy development for some people.
It’s also important to be clear about what “success” means. Pregnancy rates and live birth rates are not the same, and clinics may report them differently. What matters most is understanding which measure is being discussed and how it applies to your situation.
Crucially, freezing itself does not harm embryos. High-quality evidence shows that vitrification preserves embryo viability, with excellent thaw survival rates, and does not reduce the chance of a healthy pregnancy. This is why frozen embryo transfer is now a well-established, evidence-backed part of modern IVF, rather than a secondary option.
The takeaway is not that frozen is always better — it’s that frozen embryo transfer offers strong outcomes for many people and gives clinics more control to personalise treatment in a way that supports both safety and success.
Who is a frozen embryo transfer recommended for?
Frozen embryo transfer is recommended when it supports safety, timing, or treatment outcomes. It’s not reserved for complex cases or as a second choice; for many people, it’s the most appropriate and intentional next step in IVF. Clinics suggest FET when separating embryo creation from transfer creates a clearer, more controlled treatment pathway.
A frozen embryo transfer may be recommended if:
- You’ve had a freeze-all cycle: This approach protects physical health, particularly when hormone levels are high, and allows transfer to happen in a calmer, hormonally stable cycle.
- You want PGT testing for your embryos: Genetic testing requires embryos to be frozen while results are processed. FET allows transfer once results are available, without rushing decisions or compromising timing.
- You’ve experienced a miscarriage or a failed fresh transfer: Frozen transfer gives space for both physical recovery and emotional processing. It allows the next transfer to happen in a cycle that’s focused entirely on implantation rather than recovery.
- You’re sensitive to hormones or at risk of OHSS: People who respond strongly to stimulation, or who have certain endocrine conditions, often benefit from FET. Transferring in a later cycle reduces medical risk and supports safer treatment planning. [4]
- Timing, health, or life circumstances matter right now: FET offers flexibility. Whether that’s coordinating around work, travel, medical treatment, or mental wellbeing, freezing embryos allows treatment to move at a pace that fits real life.
PGT-A Testing: What It Is, How It Works, and Whether It’s Worth It
Pre-implantation genetic testing for aneuploidy (PGT-A) is one of the most talked-about IVF add-ons. But what does it actually tell you — and when is it worth doing?
Frozen embryo transfer step by step
A frozen embryo transfer follows a structured, carefully timed process designed to support implantation in the safest and most stable conditions possible. While protocols vary between clinics, the overall flow is consistent and intentionally paced. Knowing what happens at each stage can make the process feel clearer and more manageable.
Step 1: Cycle preparation
The first stage of a frozen embryo transfer focuses on preparing the uterus so the embryo has the best possible environment for implantation. This preparation can happen in one of two ways, depending on your cycle, medical history, and clinic recommendation.
In a natural FET, your clinic tracks your natural ovulation through blood tests and scans, timing the transfer to align with your body’s own hormone signals.
In a medicated FET, oestrogen is used to build the uterine lining, followed by progesterone to support implantation. Both approaches are widely used and evidence-based, with the choice guided by what offers the clearest timing and most consistent conditions for you.
Monitoring scans are used to check the thickness and appearance of the uterine lining, as well as confirm timing. Many clinics aim for a lining around 7–8 mm, though this is not a fixed rule and individual responses vary. Once timing is confirmed, transfer day is scheduled with precision.
Step 2: Transfer day
On transfer day, the frozen embryo is carefully thawed in the laboratory before being transferred into the uterus. The transfer itself is performed using a fine catheter under ultrasound guidance, allowing the clinician to place the embryo accurately and gently.
The procedure usually takes around 10–15 minutes and does not require anaesthetic. Most people describe the experience as mildly uncomfortable rather than painful, similar to a cervical smear. NHS guidance confirms that embryo transfer is typically straightforward and brief, and you can usually go home shortly afterwards.
Clinics often encourage a calm, unhurried environment on transfer day, but there is no need for strict rest or special positioning once the procedure is complete.
Step 3: After transfer
After embryo transfer, the focus shifts to supporting implantation and early pregnancy development. Progesterone support is continued as prescribed, as this hormone plays a key role in maintaining the uterine lining during the implantation window.
Most clinics advise returning to normal daily activities, including gentle movement and routine tasks. There is no evidence that bed rest improves outcomes, and maintaining a normal routine is often encouraged. At the same time, clinics usually recommend avoiding intense exercise, alcohol, and introducing new supplements during this period.
This stage can feel emotionally demanding, particularly during the wait for pregnancy testing. While there is little you can control biologically after transfer, staying consistent with medication and attending follow-up appointments helps keep the process clear and supported.
How many days is a frozen embryo transfer?
A frozen embryo transfer itself is a short procedure, usually completed within 10–15 minutes on the day you attend the clinic. What takes longer is the preparation cycle, which typically lasts 2–4 weeks, depending on whether you are having a natural or medicated FET. In a natural cycle, the timing is led by your own ovulation, with transfer usually planned a few days after ovulation has been confirmed through blood tests or scans. In a medicated cycle, oestrogen is used first to build the uterine lining, followed by progesterone, with transfer timed precisely after progesterone has started.
There isn’t a universal cycle day for FET. Instead, transfer is scheduled when the uterine lining is ready and hormone timing is correct, which can vary from person to person and from cycle to cycle. NHS guidance on frozen embryo transfer explains that careful monitoring and individualised timing are central to the process, rather than working to a preset calendar date. [5]
How painful is a frozen embryo transfer?
For most people, a frozen embryo transfer is described as uncomfortable rather than painful. The sensations are usually brief and manageable, and the procedure does not require anaesthetic. You may feel some pressure from the speculum, similar to a cervical smear, and mild cramping as the catheter is guided through the cervix to place the embryo in the uterus. These sensations typically ease as soon as the procedure is finished. [6]
Significant pain isn’t expected during a frozen embryo transfer. If pain does occur, clinics take it seriously and will pause or adjust the procedure to ensure your comfort and safety. The process is generally quick and straightforward, with most people able to go home shortly afterwards and resume normal activities the same day. Any discomfort is usually mild and short-lived, and that ongoing pain after transfer should always be reported to the clinic for assessment. [6]
If you’re concerned about discomfort, it’s worth discussing this with your clinic in advance.
FET implantation timeline: What happens after transfer?
After a frozen embryo transfer, the embryo begins the process of implantation — attaching to the uterine lining and starting early pregnancy development. This phase happens over several days and can feel particularly uncertain, because there’s nothing you can do to influence it once transfer is complete. Understanding the typical biological timeline helps explain why clinics ask you to wait before testing and why symptoms are an unreliable guide at this stage.
When does implantation occur after frozen embryo transfer?
For a 5-day frozen blastocyst, implantation usually follows a predictable pattern, although exact timing varies slightly from person to person:
- Day 1–2 after transfer: The blastocyst begins to attach to the uterine lining.
- Day 2–4 after transfer: Implantation continues as the embryo embeds more deeply into the lining.
- Day 4–5 after transfer: The embryo starts producing human chorionic gonadotropin (hCG), the hormone detected by pregnancy tests.
Implantation doesn’t happen instantly, and hCG is not produced at detectable levels straight away.
NHS guidance on IVF explains that pregnancy only begins once implantation has occurred and that hormone levels take time to rise, which is why pregnancy testing is usually scheduled around 16 days after embryo transfer, rather than earlier. [7]
It’s worth knowing that implantation rarely comes with clear or reliable physical signs. Spotting, cramping, and/or breast tenderness can occur during this window, but these are just as likely to be linked to progesterone support as to implantation itself. For this reason, clinics use blood or urine hCG testing — not symptoms — to assess what’s happening after a frozen embryo transfer. [8,9]
Symptoms after frozen embryo transfer (and what they mean)
After a frozen embryo transfer, many people become hyper-aware of physical changes, understandably searching for signs that the transfer has worked. This phase can feel especially confusing because the body is responding to hormones, treatment, and stress all at once. Crucially, most symptoms in the days after transfer are not reliable indicators of implantation or pregnancy, which is why clinics place far more weight on hormone testing than how you feel. Having a clearer understanding of what symptoms can — and can’t — tell you can help reduce unnecessary worry during the wait. [8,9]
It’s very normal to experience physical symptoms after a frozen embryo transfer, including:
- Cramping: Mild cramping is common and can be linked to progesterone support, the uterus responding to hormonal changes, or simply normal pelvic activity. It does not confirm or rule out implantation.
- Bloating: Progesterone can slow digestion and cause fluid retention, leading to bloating or abdominal discomfort. This is a frequent side effect of IVF medication.
- Fatigue: Feeling unusually tired is also common. Progesterone has a sedating effect, and emotional strain during the waiting period can amplify exhaustion.
- Breast tenderness: Sore or heavy breasts are a well-known progesterone side effect and occur whether or not implantation has happened.
NHS guidance explains that symptoms such as cramping, bloating, and breast tenderness are common after embryo transfer and are often related to hormone treatment rather than early pregnancy itself. [7]
Implantation bleeding after embryo transfer
Some people notice light spotting between day 7 and day 10 after embryo transfer, which is often described as implantation bleeding. Implantation bleeding after IVF is possible, but it isn’t a reliable or necessary sign of pregnancy. Many successful pregnancies occur without any bleeding at all, and spotting can also be caused by progesterone, cervical sensitivity, or vaginal pessaries. [10]
Pregnancy testing after frozen embryo transfer
Pregnancy testing after a frozen embryo transfer is often described as one of the hardest parts of IVF. There’s a strong urge to look for certainty as early as possible, especially after weeks or months of treatment. The challenge is that biology moves more slowly than hope, and testing too soon can give results that are confusing or misleading. Understanding how and when pregnancy hormones rise helps explain why clinics give very specific guidance on testing after FET.
When can you test after embryo transfer?
Pregnancy tests detect human chorionic gonadotropin (hCG), a hormone produced only after implantation has begun. After a frozen embryo transfer, implantation usually happens over several days, and hCG levels rise gradually rather than all at once. Testing before hCG has reached a detectable level can result in a false negative, even if implantation has occurred.
Home urine tests can detect hCG, but timing makes a significant difference to how reliable the result is day 12–16 post transfer. Most UK clinics schedule a blood test within this window because blood tests can detect lower levels of hCG and provide a clearer answer.
Negative pregnancy test after embryo transfer
A negative test can mean very different things depending on the day it’s taken.
- Day 7 after embryo transfer: A negative test at day 7 is extremely common and not conclusive. At this stage, implantation may still be ongoing or hCG levels may simply be too low to detect.
- Day 9–11 after embryo transfer: Some people will see positive tests during this window, but many viable pregnancies still test negative. A negative result here is disappointing, but it does not automatically mean the transfer has failed.
- Day 12–16 after embryo transfer: By day 12–14, pregnancy tests are much more reliable. Persistent negative results at this stage are more meaningful, which is why clinics often use this window for official testing and next-step planning.
Period after frozen embryo transfer
If implantation doesn’t occur, progesterone support is usually stopped on clinic advice. Once progesterone is withdrawn, bleeding typically begins within a few days to a week, though the exact timing varies between individuals and protocols. This bleeding marks the start of your next cycle rather than a delayed or abnormal period.
Clinics provide guidance on when to expect bleeding and when to get in touch if it doesn’t start as expected.
Are you considered pregnant after frozen embryo transfer?
After a frozen embryo transfer, pregnancy is clinically defined as beginning once the embryo has implanted and hCG is detectable in blood or urine. This is the point at which clinics confirm a pregnancy and begin monitoring it.
At the same time, how you personally think about pregnancy after transfer is your choice. Some people feel pregnant from the moment the embryo is transferred, while others wait for a positive test or a scan. There isn’t a right or wrong way to hold that moment, especially after everything it can take to reach transfer day.
Pregnancy dating in IVF can also feel counterintuitive. Weeks of pregnancy aren’t counted from the day of embryo transfer, but from the point equivalent to ovulation, which in IVF is egg collection. This system is used across NHS and private fertility care to keep pregnancy dating consistent with how pregnancies are measured after conception without IVF.
How many weeks pregnant are you after a 5-day transfer?
If you’ve had a 5-day blastocyst transfer, you are considered 2 weeks and 5 days pregnant on the day of transfer. This is because a day-5 embryo has already completed five days of development before transfer, and IVF pregnancy dating accounts for that early growth. As a result, even though implantation may still be underway, pregnancy is dated in weeks rather than days post transfer.
The numbers can feel surprising at first, especially during the early days after transfer, but this dating system ensures scans, blood tests, and expected milestones are interpreted accurately by your care team.
Is embryo transfer day considered day 1?
No. Embryo transfer day is not counted as cycle day 1. Cycle day 1 refers to the first day of a menstrual bleed, while embryo transfer happens later in the cycle, once the uterine lining has been prepared and is ready for implantation. After transfer, days are usually counted as days post transfer (DPT), which is why clinics and patients talk about “day 5 after transfer” or “day 10 after transfer” rather than restarting the cycle count. Understanding this distinction helps make sense of testing timelines and why pregnancy dates are calculated differently in IVF.
How common is miscarriage after frozen embryo transfer?
Miscarriage after a frozen embryo transfer is understandably one of the biggest concerns people carry into early pregnancy. The most important thing to know is that miscarriage risk after FET is shaped by the same factors that influence miscarriage in any pregnancy: embryo genetics, age, and how the uterus responds to implantation. The freezing and thawing process itself does not increase the risk of miscarriage. In fact, the HFEA reports the pregnancy rate at 41% and the live birth rate at 32% for frozen embryo transfers (unfortunately a miscarriage rate of around 22%), and for fresh embryo transfers, the pregnancy rate is 31% with a live birth rate of 24% (a miscarriage rate of 23%, marginally higher). [3]
For some people, frozen embryo transfer may even offer indirect reassurance. FET allows embryos to be transferred in a hormonally stable cycle, and when genetic testing such as PGT is used, it can reduce the likelihood of transferring embryos with chromosomal abnormalities. While no IVF method can remove miscarriage risk entirely, current evidence shows that frozen embryo transfer does not add risk — and remains a safe, established approach to building a pregnancy.
If you’ve experienced miscarriage before, clinics often take this history into account when planning an FET cycle, including how the lining is prepared and what additional monitoring is offered in early pregnancy.
What are the advantages and disadvantages of frozen embryo transfer?
Frozen embryo transfer is now a routine part of IVF in the UK, but like any treatment approach, it comes with both benefits and trade-offs. For many people, the advantages relate to safety, flexibility, and clinical control. The disadvantages are usually practical or emotional rather than biological, and they vary depending on how treatment is funded and how cycles are structured. Looking at both sides together helps set realistic expectations and supports informed decision-making. [2,7]
| Advantages | Disadvantages |
|---|---|
| Flexible timing: Transfer happens in a later cycle, making it easier to plan around recovery, work, or personal circumstances. | Delay between retrieval and transfer: The waiting period between embryo creation and transfer can feel frustrating. |
| Lower risk of OHSS: Transferring embryos after hormone levels settle reduces OHSS risk in people who respond strongly to stimulation. | Additional medication in medicated cycles: Some FET cycles require oestrogen and progesterone, which can bring side effects and monitoring. |
| Compatible with PGT testing: Embryos are frozen while genetic test results are processed, making FET essential for PGT. | Emotional strain of waiting: The pause between cycles can add emotional pressure, especially after a long fertility path. |
| More controlled uterine environment: Transfer takes place in a natural or carefully prepared cycle that may support implantation. | Additional costs in private treatment: Private care often includes separate fees for storage, medication, and the transfer. |
| Greater clinic scheduling consistency: Frozen transfers are less likely to be cancelled at short notice than fresh transfers affected by late hormone changes or OHSS risk. | Longer overall treatment timeline: FET extends the IVF process, which some people find emotionally harder than a faster fresh transfer. |
| Better separation of decisions: FET spreads embryo creation, testing, and transfer over time, reducing pressure when choosing which embryo to transfer. | Storage decisions and fees: Embryo storage involves ongoing costs and future decisions about unused embryos. |
Overall, frozen embryo transfer offers clear clinical advantages for many people, particularly around safety and flexibility. The downsides tend to relate to timing, cost, and emotional load rather than effectiveness. Understanding both helps you weigh whether FET feels like the right approach for your treatment and circumstances, with support from your fertility team.
How can I make my frozen embryo transfer successful?
Once a frozen embryo transfer has taken place, it’s natural to want to do everything possible to influence the outcome. The reality is that most of what determines success happens before transfer, through embryo quality, uterine readiness, and timing. After transfer, the most effective approach is a steady, evidence-led one that supports your body and avoids unnecessary pressure.
- Take medication as prescribed: Progesterone and any other prescribed medication play a central role in supporting the uterine lining during implantation. Taking doses at the correct time and continuing them for the full duration advised by your clinic is one of the most important things you can control.
- Attend all monitoring and follow-up appointments: Blood tests and scans allow clinics to assess hormone levels and early pregnancy progression accurately. Attending appointments as scheduled ensures any concerns are picked up early and managed appropriately.
- Maintain normal, routine daily activity: Gentle movement and normal routines are encouraged. Returning to everyday activity is safe and appropriate for most people, but it’s worth checking with your fertility clinic for your recommendations.
Just as importantly, it helps to know what doesn’t improve outcomes. There’s no strong evidence that prolonged bed rest, strict fertility diets, or unproven supplements increase the chance of implantation after FET.
The most supportive approach after frozen embryo transfer is consistency rather than intensity. Following your clinic’s guidance, keeping medication steady, and allowing your body to do what it needs to do creates the clearest conditions for implantation — without placing extra pressure on yourself during an already demanding stage of treatment.
How much does a frozen embryo transfer cost in the UK?
A frozen embryo transfer (FET) usually costs less than a full IVF cycle because it doesn’t involve egg collection or ovarian stimulation. However, the price can still vary widely depending on the clinic, what’s included in the fee, and whether your cycle is natural or medicated. Understanding the true cost upfront is important, especially as many people go through more than one embryo transfer before achieving a live birth.
In private fertility clinics across the UK, a frozen embryo transfer typically costs between £1,200 and £2,500 per transfer, with many people paying around £1,800 to £2,000 in practice. This usually covers the embryo thaw, the transfer procedure itself, and embryology and clinical time. That headline figure doesn’t always include everything you’ll need, though. Medicated FET cycles often involve additional costs for oestrogen and progesterone, which can add £100–£400, and some clinics charge separately for monitoring scans, blood tests, or the HFEA fee. Ongoing embryo storage fees, usually billed annually, are another cost to factor in. [11]
This matters in the wider IVF picture because most people need more than one embryo transfer to have a child. HFEA data shows that, on average, patients go through around 3 embryo transfers, meaning that even relatively modest per-transfer costs can add up over time. [12]
Before starting a frozen embryo transfer cycle, it’s worth asking your clinic for a fully costed treatment plan that clearly sets out what is included in the FET fee and what will be charged separately. Transparency here makes a real difference to budgeting and reduces the risk of unexpected costs later on.
NHS-funded frozen embryo transfer
If you’re eligible for NHS-funded IVF, frozen embryo transfers are usually included as part of that funding, provided embryos are available and your local criteria are met. Eligibility depends on where you live, your age, medical history, and personal circumstances, as IVF funding is decided by local Integrated Care Boards. Access to IVF, including frozen embryo transfer, varies across the UK and is often limited to one funded cycle in many areas. [7]
Nationally, only around 27% of IVF cycles are NHS-funded, and many regions fund fewer embryo transfers than recommended by NICE guidelines. This means that even people who receive some NHS-funded treatment may need to self-fund additional frozen embryo transfers if they have embryos remaining. These regional differences in access and funding, which is why it’s important to check your local eligibility and understand exactly what is covered before starting treatment. [13]
If you’re unsure where you stand, checking eligibility early can help you plan realistically — whether that means relying on NHS funding, budgeting for private frozen embryo transfers, or a combination of both.
NHS IVF Eligibility Calculator
Trying to find out if you qualify for NHS-funded IVF or IUI treatment? Between postcode rules and unclear criteria, it can be hard to know where you stand.
Deciding whether frozen embryo transfer is right for you
Frozen embryo transfer sits at the centre of modern IVF care because it allows treatment to be planned with intention, rather than rushed by circumstance. For many people, FET offers a way to align medical safety, embryo quality, and timing in a way that feels considered and controlled, without compromising the chance of success.
Whether frozen embryo transfer is right for you depends on a combination of factors: your medical history, how your body responds to stimulation, the number and stage of embryos available, and whether genetic testing or recovery time is part of your plan. Some people value the flexibility FET offers, while others find reassurance in transferring in a calmer, hormonally stable cycle. There is no universal “best” approach — only what fits your body, your priorities, and your wider life at this moment.
Clarity matters more than certainty. A supportive clinic will take the time to explain why frozen embryo transfer is being recommended in your specific case, what the trade-offs are, and how it fits into your overall fertility path. When you understand the reasoning behind the plan, it becomes easier to move forward with confidence, knowing that the decisions being made are intentional, evidence-led, and centred on you.
Frozen embryo transfer FAQs
Can frozen embryos result in twins?
Yes, it’s possible. Even when a single embryo is transferred, identical twins can occur if the embryo splits after transfer. This is known as monozygotic twinning and happens rarely, but slightly more often in IVF than in unassisted conception. The HFEA explains that while single embryo transfer significantly reduces the risk of twins, it doesn’t remove it entirely. [14,15]
What is the longest an embryo has been frozen?
There are documented cases of healthy births from embryos that were frozen for over 30 years. These outcomes support what clinics already see in practice: embryos do not “age” while frozen. The HFEA confirms that long-term embryo storage is safe and well established when embryos are frozen using modern vitrification techniques. [16,17]
Does it matter how long an embryo is frozen?
Current evidence shows that how long an embryo is stored does not reduce the chance of pregnancy or live birth, as long as it remains within legal storage limits. Embryos are kept in a suspended state, meaning no biological changes occur over time. In the UK, embryo storage is regulated by the HFEA, which sets clear rules on consent, storage duration, and extensions. [17,18]
How soon after a failed frozen embryo transfer can I try again?
For many people, another frozen embryo transfer can take place in the next menstrual cycle, provided there are no medical reasons to delay. Physically, the body often doesn’t need a long recovery period after FET. Clinics also consider emotional readiness, previous outcomes, and whether any changes to the treatment plan are needed.
Can you drink alcohol after embryo transfer?
Most clinics advise avoiding alcohol during the implantation window and while waiting for a pregnancy test. This is partly precautionary and partly practical, as alcohol can interfere with early pregnancy development if implantation has occurred. The NHS advises avoiding alcohol when trying to conceive and during early pregnancy, which is why clinics usually recommend pausing alcohol after embryo transfer. [19,20,21]
How long to rest after frozen embryo transfer?
There is no evidence that bed rest improves implantation or pregnancy rates after embryo transfer. Most clinics recommend returning to normal daily activity the same day, while avoiding very strenuous exercise.
Sources
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