At the crucial stage of IVF treatment, many couples find it difficult to choose between fresh and frozen embryo transfer. With the debate going around the two, each method has its own set of benefits and risks patients need to consider.
Many fertility studies have proven that women who underwent frozen embryo transfer (FET) results in a higher chance of live birth than fresh embryo transfer (ET) following an IVF treatment. In some cases, fresh embryo transfer could be a better option for your fertility success depending on your situation.
But how do you decide which transfer is right for you?
We’re here to explain how fresh and frozen embryos differ from each other so you can make the best choice for your fertility journey.
Understanding Embryo Transfer in IVF
Before we distinguish these two options, let’s start by understanding their similarities.
Both fresh and frozen embryo transfer involve taking the fertilized egg and sperm for implantation. When the intended mother’s uterine lining is ready, a thin flexible catheter passes through the cervix to implant the newly-formed embryo.
As part of the IVF cycle, your fertility doctor will transfer the embryo by a pelvic ultrasound to ensure that the placement is precise.
Choosing between fresh and frozen embryo transfer depends on age, health conditions and personal preferences. While success is more likely to happen with frozen transfer, we transfer fresh embryos in unique cases.
Fresh Embryo Transfer
Fresh embryo transfer occurs once the eggs and sperm have been fertilized. Three to five days after the egg retrieval, our doctor will synchronize the transfer with a woman’s natural cycle.
Advantages of Fresh Transfer
In cases where frozen embryo is not medically advisable, fresh transfers offer the following advantages:
- Straightforward process. Patients no longer need to wait more than five days for transfer after the egg retrieval.
- Reduces waiting time. The immediate insertion of a fully-developed embryo in a favorable uterine environment can alleviate anxiety of patients.
- Optimal for few embryos. It offers a good option for women with fewer, lower-quality embryos that may not survive the thawing process.
Potential Risks of Fresh Transfer
Fresh embryo transfers are often avoided during the following situations:
- Unreceptive endometrium. High hormone levels create a less receptive endometrium, leading to failed implantation.
- Lower success rates. Success rates may be lower for women with certain conditions.
- Ovarian hyperstimulation syndrome (OHSS). Doctors avoid fresh transfers for any complications related to ovaries to prevent health risks.
Frozen Embryo Transfer
In a frozen embryo transfer, embryos are frozen for months or even years through vitrification. Your fertility doctor will implant one or more thawed embryos into the uterus in a future cycle.
Advantages of Frozen Transfer
This method provides an opportunity for patients to pause and plan. The flexibility in timing allows for significant advantages such as:
- Help your body recover faster. The body can rest and return to its natural state before attempting implantation.
- Higher success rates. Often leads to higher pregnancy rates and healthier babies, which is beneficial for patients who have experienced failed IVF multiple times.
- Optimal window of implantation (WOI). FET allows the uterus to recover from high hormone levels used in stimulation and prevents asymmetry.
- Reduced pressure. For couples with demanding lifestyles, FET ensures the viability of embryos to maintain quality until you’re ready for transfer.
- Genetic Testing for PGT-A. It allows fertility specialists to check for abnormalities and select the gender before transfer. This testing can prevent implantation failure, miscarriage, or birth defects.
Potential Risks of Frozen Transfer
While it is considered rare, here are the risks of embryo damage during the thawing process:
- Embryo survival risk. Embryo may become unviable during the embryo thawing which reduces the number of available embryos.
- Time delays. Waiting for a new cycle to prepare the uterus can feel emotionally tough.
- Not always ideal. A fresh transfer may be as effective for younger women with good embryo quality.
Comparing Fresh and Frozen Embryo Transfer Success Rates
Often, clinics who recommend using FET achieve higher success rates in IVF rather than fresh transfers. Here are studies we’ve gathered about both options:
- The New England Journal of Medicine released a study in 2018 indicating that frozen transfers lead to higher live birth rates for women with polycystic ovary syndrome (PCOS).
- Babies born from frozen embryos exhibit lower risks of preterm birth and low birth weights compared to fresh transfers. Fresh transfers may carry a higher risk to pregnancy complications if the ovaries are overstimulated.
- In a 2020 study, women with normal regular menstrual cycles and hormone levels may benefit from fresh transfers. It may be equally effective as FET if there is no sign of OHSS.
Another research in 2019 shows that women below the age of 35 who take part in any of these two transfers increase their chances of attaining high quality embryos, while women above the age of 35 achieve the opposite.
Choosing the Best Option with your Fertility Doctor
With the proper guidance and information, your fertility specialist will help you understand several factors to consider before choosing the best embryo transfer.
When is Fresh Transfer Preferred?
- A woman is under 35 with healthy eggs.
- Stable hormone levels during IVF.
- No risk of OHSS or other complications.
- A good-quality embryo is available.
When is Frozen Transfer Considered?
- Previous fresh transfer attempts were unsuccessful.
- Embryos are being genetically tested before implantation.
- The endometrium is not receptive for immediate transfer.
- OHSS in a woman is present.
- More time to recover emotionally and physically.
It’s important to discuss with your doctor what you and your partner feels right so you can receive the right medical support.
Personalizing Your Embryo Transfer Cycle
Both fresh and frozen embryo transfer depends on how your body responds to treatment. Our fertility specialists will take steps to minimize risks during your IVF cycle and take careful consideration of your individual circumstances.
At Fertility Philippines, we are here to understand your needs to recommend the best embryo transfer for you. We can provide you tailored guidance based on your health conditions, preferences, and goals.
Contact us to begin your fertility journey today.
Disclaimer: This blog does not intend to represent any medical advice, diagnosis, or treatment. For personalized recommendations, consult with your fertility specialist. Any information herein does not replace the expertise determined by a physician.