Single Embryo Transfer: Understanding The Science And Safety Behind Your Fertility Doctor’s Decision
Fertility treatments can be a complex and emotional journey. At Audubon Fertility, we believe that every patient deserves personalized care and individualized treatment plans. That's why we take the time to understand your unique circumstances and goals before making any recommendations. In this blog post, we will discuss the science and safety of single embryo transfer. We will also explain the factors that your fertility doctor will consider when making a decision about your treatment plan.
The Journey of Fertility Treatment
When you are unable to conceive naturally, you may be faced with the decision to pursue
fertility treatments. There are many different types of fertility treatments available, each with its own advantages and disadvantages.
One of the most common fertility treatments is in vitro fertilization (IVF). IVF involves retrieving eggs from your ovaries, fertilizing them with sperm in a laboratory, and then transferring the embryos back into your uterus.
If you are considering IVF, you will need to work with a fertility doctor to develop a treatment plan. Your doctor will consider your age, medical history, and other factors when making recommendations.
What Is Single Embryo Transfer (SET)?
Single embryo transfer (SET) is when only one embryo is transferred back into the uterus during in vitro fertilization (IVF). This is done to reduce the risk of a multiple pregnancy. Multiple pregnancies can be dangerous for both the mother and the babies. They can increase the risk of preterm birth, low birth weight, and other complications.
SET is a safe and effective way to increase your chances of having a successful pregnancy without the risks of multiple pregnancy.
Most reputable IVF practices in the U.S. utilize ASRM guidelines when deciding on the number of embryos to transfer. The American Society for Reproductive Medicine (ASRM) published guidelines in 2021 on the recommended number of embryos to transfer in IVF to optimize the chances of a successful pregnancy while minimizing the risks associated with multiple pregnancies. These guidelines were designed to promote the health and well-being of both the mother and potential offspring.
The 2021 ASRM guidelines are as follows:
Patients with a favorable prognosis:
Transfer of a euploid (genetically normal) embryo should be limited to one, regardless of patient age.
Patients <35 years of age should be strongly encouraged to receive a single-embryo transfer, regardless of the embryo stage.
For patients between 35 and 37 years of age, strong consideration should be made for a single-embryo transfer.
For patients between 38 and 40 years of age, no more than 3 untested cleavage-stage (day 3) or 2 blastocyst stage (day 5) embryos should be transferred.
Patients 41–42 years of age should plan to receive no more than 4 untested cleavage-stage embryos or 3 blastocysts.
In each of the preceding age groups, patients who do not meet the criteria for a favorable prognosis may have an additional embryo transferred according to their individual circumstances.
If otherwise favorable patients fail to conceive after multiple cycles with high-quality embryo(s) transferred, the physicians and patients may consider proceeding with an additional embryo to be transferred.
Patients with a coexisting medical condition for which a multiple pregnancy may increase the risk of significant morbidity should not have more than one embryo transferred.
In women over 43 years of age, there are insufficient data to recommend a limit on the number of embryos to transfer when the patient uses her own oocytes. Caution should be exercised as the risk associated with multiple pregnancy increases dramatically with advancing maternal age.
In donor-oocyte cycles, the age of the donor should be used to determine the appropriate number of embryos to transfer. For example, when the donor is <38 years of age and other favorable criteria exist, single-embryo transfer should be planned.
Single-embryo transfer should be strongly recommended in all gestational carrier (GC) cycles, given the health risks associated with multiple gestations for the GC. At a minimum, it is recommended to follow age-related limits on the number of embryos to transfer in GC cycles, on the basis of the age of the woman who produced the oocytes (either the intended parent or oocyte donor).
In FET (frozen embryo transfer) cycles, favorable characteristics should be on the basis of the age of the woman when the embryos were cryopreserved and include the presence of high-quality vitrified embryos, euploid embryos, first FET cycle, or previous live birth after a prior transfer with sibling embryo(s). Embryo transfer numbers should not exceed the recommended limit on the number of fresh embryos transferred for each age group.
Safety And Success Rates
National data from SART demonstrates that clinics that performed higher rates of elective single-embryo transfer in women aged <38 years have decreased rates of multiple gestations with no signiﬁcant impact on live birth rates. In addition, preimplantation genetic testing for aneuploidy maybe a tool to reduce the rate of multiple gestations, especially in women >37 years of age. In women <42 years, transferring a single euploid blastocyst resulted in pregnancy rates similar to those of transferring 2 untested blastocysts while dramatically reducing the risk of twins.
The success rates of single embryo transfer vary depending on a number of factors, including your age, embryo quality, and medical history. However, overall, the success rates of SET are comparable to the success rates of multiple embryo transfers.
Factors Influencing The Doctor's Decision
There are a number of factors that your fertility doctor will consider when making a decision about whether to recommend single embryo transfer. These factors include:
Patient Age: A woman’s age when she undergoes IVF is the most important factor affecting the success rates of IVF. As women get older, egg quality declines and success rates decline. Your doctor is more likely to encourage single embryo transfer if you are <38 years of age.
Embryo Quality: The quality of your embryos is also an important factor affecting success rates. Higher-quality embryos are more likely to implant and result in a successful pregnancy. If you have good-quality embryos, your doctor may be more likely to recommend single embryo transfer.
Personalized Treatment Plans: Your doctor will also consider your individual circumstances and goals when making a decision about whether to recommend single embryo transfer. For example, your doctor may take into consideration a history of failed IVF cycles.
Medical History: Your medical history, such as any underlying health conditions, may also be a factor in your doctor's decision. For example, if you have a history of preterm delivery, high blood pressure or diabetes, your doctor may be more likely to recommend single embryo transfer in order to reduce the risks associated with multiple pregnancy.
Patient Involvement And Informed Decision-Making
It is important for you to be involved in the decision-making process about your fertility treatment. You should have a clear understanding of the risks and benefits of single embryo transfer before making a decision.
Your fertility doctor should be willing to answer all of your questions and explain the reasons for their recommendations. You should feel comfortable discussing your preferences and goals so that you can make the best decision for yourself.
The Role of Audubon Fertility
At Audubon Fertility, we are committed to providing our patients with the highest quality care. We believe that every patient deserves personalized attention and individualized treatment plans.
Our team of experienced fertility specialists has extensive experience in single embryo transfer. We are committed to providing you with the information and support you need to make informed decisions about your treatment.
If you are considering fertility treatment, please contact us to schedule a consultation. We would be happy to discuss your individual circumstances and goals and help you create a treatment plan that is right for you.
Single embryo transfer is a safe and effective way to increase your chances of having a successful pregnancy without the risks of multiple pregnancy.
If you are considering fertility treatment, it is important to talk to your doctor about the risks and benefits of single embryo transfer. With careful planning and informed decision-making, you can increase your chances of achieving your fertility goals.
To schedule a consultation with a fertility specialist at Audubon Fertility, please visit our website at Audubon Fertility.