Frozen Embryo Transfer (FET) is a common type of assisted reproductive technology (ART). If you’ve already completed an IVF cycle, you might be a candidate for FET.
With FET, an embryo from a prior IVF cycle is thawed and transferred into your uterus. Compared to a fresh embryo transfer, FET offers more flexibility in timing.
The FET process can be an emotional rollercoaster. The timing has to be just right, and the medical interventions can cause anxiety and stress.
That’s why we’ve created this guide to the FET timeline. We’ll walk you through the process and offer practical tips to help you prepare for a successful cycle.
Understanding Frozen Embryo Transfer (FET)
If you’re trying to conceive through in vitro fertilization (IVF), you may encounter the term “FET.” Here’s what it means:
What is FET?
Frozen embryo transfer (FET) is a procedure in which an embryo that has been frozen after a previous IVF cycle is thawed and transferred to a woman’s uterus.
A typical IVF cycle includes stimulating the ovaries with medication, retrieving the eggs, fertilizing the eggs in a lab, and allowing the embryos to develop for a few days. At that point, the embryos can be frozen (cryopreserved) for use in a later FET cycle.
Why choose FET?
There are several benefits to using frozen embryo transfer rather than transferring a “fresh” embryo right away:
- FET allows for more flexibility in timing, so the uterine lining can be optimally prepared for implantation.
- FET reduces the amount of ovarian stimulation needed.
- FET provides an opportunity for preimplantation genetic testing (PGT) to screen for genetic abnormalities.
Research shows that success rates with FET are comparable to, or even higher than, those seen with fresh embryo transfers, possibly due to improved receptivity of the uterus in FET cycles.
Hormonally Supported vs. Natural FET Cycles
There are two main types of frozen embryo transfer (FET) cycles: hormonally supported and natural. In a hormonally supported cycle, doctors use medications to control your hormones. Estrogen supplements thicken the uterine lining, and progesterone readies the lining for implantation.
Natural FET cycles, on the other hand, rely on your body’s own hormone production. Your doctor will monitor your hormone levels with blood tests and ultrasounds. Natural cycles are generally a good option for people who have regular periods and healthy hormone levels.
The right type of cycle for you will depend on your own situation and your doctor’s advice.
The FET Timeline: A Step-by-Step Guide
A frozen embryo transfer (FET) cycle has several steps. Here’s what you can expect as you move through the process.
Baseline Visit (Cycle Day 2-4)
The goal of this visit is to make sure your ovaries and uterus are ready for the transfer.
During this appointment, you’ll likely have a transvaginal ultrasound to check out your ovaries and uterus. You’ll probably also have some blood drawn to measure your hormone levels, particularly estradiol and progesterone.
If your uterine lining is too thin, your doctor may start you on estrogen supplements.
Mid-Cycle Monitoring (Typically Day 10-14)
The purpose of this monitoring is to keep tabs on the thickness of your uterine lining.
You’ll probably have another transvaginal ultrasound so the doctor can measure the thickness of your endometrium, which ideally should be around 7-8 mm. You’ll also have bloodwork to check your estrogen levels.
Depending on the thickness of your uterine lining, your estrogen dosage may be adjusted.
Progesterone Start
You’ll usually begin taking progesterone 5-7 days before the scheduled embryo transfer, depending on the age of the embryo.
Progesterone can be administered in a few different ways: through intramuscular injection, via vaginal suppositories, or as an oral medication.
Pre-Transfer Check
This is the final check to make sure your uterine lining is thick enough and that your hormone levels are optimal.
You’ll have another ultrasound to confirm that your endometrial thickness is adequate. You’ll also have bloodwork to confirm that your hormone levels are where they need to be.
The Embryo Transfer
The embryo transfer usually happens 5-7 days after you start taking progesterone.
The procedure itself is an outpatient procedure and doesn’t require anesthesia. The doctor will gently place the embryo into your uterus using a catheter.
Important tip: Be sure to arrive with a full bladder. This helps the doctor visualize the uterus more clearly.
Post-Transfer Monitoring
It’s critical to continue taking all prescribed fertility medications after the transfer, exactly as directed.
About 9-14 days after the embryo transfer, you’ll have bloodwork (specifically, an hCG test) to see if the transfer resulted in pregnancy.
Depending on the results of the hCG test, you may need to return for subsequent tests and ultrasounds.
Preparing for Your FET Cycle: Practical Tips
A frozen embryo transfer (FET) cycle can feel overwhelming. Here are some practical tips to help you prepare and hopefully increase your chances of success:
- Organize and Take Medications On Time: Medication management is crucial for a successful cycle. Use pill organizers, set alarms, and keep a detailed log to ensure you’re taking everything correctly.
- Consider Your Treatment Calendar: FET cycles involve lots of appointments and medications. Use a physical planner or calendar app to keep track of everything. Being organized can reduce stress significantly.
- Stock Up on Entertainment: The two-week wait after your transfer can feel like an eternity. Download movies, start a new book series, or find a new hobby to keep yourself occupied and distracted.
- Get Plenty of Sleep: Aim for 7-9 hours of sleep per night. Studies suggest that getting less sleep can actually lower pregnancy rates. Make sleep a priority!
- Prepare and Eat IVF-FET Safe Meals: Focus on eating a healthy diet rich in high-fat, low-carb, and antioxidant-rich foods. Think avocados, nuts, seeds, olive oil, leafy greens, and berries. These foods are thought to support implantation.
- Avoid Endocrine-Disrupting Chemicals (EDCs): Minimize your exposure to plastics, pesticides, and certain cosmetics. These chemicals can interfere with your hormones. Choose organic produce, use glass containers, and opt for natural beauty products.
- Plan Logistics Before Your Transfer: Arrange transportation to and from your appointments, figure out childcare if needed, and take time off from work. Having these details sorted out in advance will reduce your stress on transfer day.
- Avoid Sexual Intercourse After the Transfer: Discuss intercourse with your doctor before FET procedures. Many doctors recommend avoiding it after the transfer.
- Keep Taking Fertility Medications After the Transfer: Don’t stop taking your fertility medications unless your doctor tells you to. These medications are crucial for supporting the pregnancy in its early stages.
What are the chances of a successful FET?
It’s important to remember that success rates vary widely depending on a few things, including:
- Your age
- The quality of the embryo
- The receptivity of your uterine lining
- The clinic’s expertise
Generally speaking, women 35 and younger have around a 60% chance of pregnancy per embryo transfer. For women over 40, that drops to about 20%.
The best way to get a personalized estimate of your chances is to talk with your fertility specialist. They can assess your specific situation and give you a more accurate prediction.
Frequently Asked Questions
What are the most critical days after a FET?
The days immediately following a frozen embryo transfer (FET) are crucial. Days 1-5 are when the embryo is hopefully working to implant in your uterine lining. This is a delicate period, so it’s a good idea to take it easy and follow your doctor’s specific instructions.
How long after FET does implantation occur?
Implantation typically occurs between 1 and 5 days after the FET. It’s during this window that the embryo attaches to the uterine wall and begins to develop. Some women may experience implantation bleeding, but not everyone does.
How many days after your period is a frozen embryo transfer?
The timing of your FET depends on your specific protocol, but generally, it’s scheduled based on your menstrual cycle. In a medicated cycle, the transfer usually takes place around days 19-21 of your cycle, after you’ve been taking estrogen to thicken your uterine lining.
What is the ideal time for FET?
The ideal time for an FET is when your uterine lining is receptive and ready to support the embryo. This is usually when the endometrium has reached a thickness of at least 7-8mm. Your doctor will monitor your lining with ultrasounds and adjust your medication as needed to optimize the timing for the transfer.
In Conclusion
Knowing what to expect during each step of a frozen embryo transfer (FET) can help you feel more in control and less anxious. It’s vital to follow your medical team’s guidance and attend all scheduled appointments.
Remember that lifestyle factors like diet and exercise can play a role in your success, and managing stress is crucial. Lean on your healthcare providers, connect with support groups, and talk with the people you love.
If you’re undergoing FET, you’re not alone. We hope this information has been helpful, and we wish you the very best on your journey.