Single Embryo Transfer
What is elective single embryo transfer (eSET)?
Elective single-embryo transfer (eSET) is a procedure in which one embryo, selected from a larger number of available embryos, is placed in the uterus or fallopian tube. The embryo selected for eSET might be from a previous IVF cycle (e.g., cryopreserved embryos (frozen)) or from the current fresh IVF cycle that yielded more than one embryo. The remaining embryos may be set aside for future use or cryopreservation.
eSET helps women avoid several risks to their own health that are associated with carrying multiples. It also helps families achieve success while preventing some risks known to be associated with giving birth to twins or what is called "high order multiple births" (three or more children born at the same time). Infants born in multiple births are more often born early (preterm), are smaller (low birth weight) and experience more adverse health outcomes than singleton infants. There is consensus among experts that the desired outcome of ART is a healthy singleton infant.
This video presents information regarding a decision facing an increasing number of ART patients.
Is eSET appropriate for me?
Research studies assesses the chances of success (pregnancy and live birth) based upon the number of embryos transferred during an ART procedure. This research found that among women with a good chance of success with ART, those who chose to have a single embryo transferred had a similar number of live-birth deliveries compared to those who chose to transfer multiple embryos, but almost all of the infants they delivered were singletons.
The guidelines on number of embryos transferred were developed by the Practice Committees of the American Society for Reproductive Medicine (ASRM) and the Society for Assisted Reproductive Technology (SART). According to these guidelines, single embryo transfer should be considered for patients with favorable prognosis, usually women aged 35 years or younger and with eggs or embryos of good quality. These guidelines have been developed to assist physicians with clinical decisions regarding the care of their patients. They are not intended to be a protocol to be applied in all situations, and cannot substitute for the individual judgment of the treating physicians based on their knowledge of their patients and specific circumstances. The complete guidelines on number of embryos transferred in ART cycles can be found on SART Web site.
What if I have waited and tried many times to get pregnant unsuccessfully?
The desire for childbearing and parenthood can be compelling. There are so many decisions to make as you determine whether ART is the right option for you and identify clinics that provide services. Remember, the best decisions are knowing your options and selecting one compatible with your beliefs and values about pregnancy, childbearing, and parenting.
Women experiencing infertility or wanting to have another child may find having multiples to be an “acceptable risk” when considering ART services. But as you see in our videos, circumstances and thoughts may change as you go through this journey. We also find that many who call CDC mention feeling pressured to make the “right” decision in a short period of time, perhaps without adequate time to talk through the outcomes of your decision with a partner. We urge you to consider the value of single embryo transfer as option BEFORE starting ART services.
What are the risks associated with multiple births?
- Multiple births increase the risk of premature birth and low birth weight in infants. This can affect survival and well-being of newborns. These babies may require special care immediately after birth and at times, can face life-long problems such as developmental disabilities and delays.
- Women who carry multiples may be more likely to need Caesarean sections which may require a longer period of recovery, and at times, can increase the risk of hemorrhage during and after delivery.
- Some who become pregnant with multiples may find one or more cannot survive to term or even a premature birth. This may lead to a medical need to perform fetal reduction.
- Women older than age 35 have an increased risk of pregnancy complications, some of which could be life threatening. Carrying multiples adds to this risk.
How do I decide if eSET is for me?
Every person is different and every effort to begin or expand a family is different. Here are some suggestions that you might consider:
- Take a few moments to review what are the “practical” and personal limits related to your choice. For example, women who wish to breastfeed may find it even more challenging when they are mothers of multiples. Others speak of the difficulty in finding affordable and reliable child care options outside or in the home. Even the logistics of transporting multiples can be daunting to some, especially for keeping well-child appointments, seeking emergency care, or taking care of routine housekeeping duties.
- Identify the network of support you need now and will need during and after pregnancy.
- What can your employer or your partner’s employer provide in benefits (e.g., sick pay) or work options (e.g., alternative work schedules, telecommuting)?
- What would be the extra demands that multiples might place on your lifestyle?
- Do you have friends and family who can help, if needed?
- How long can you count on them to help?
- Discuss single embryo transfer and other options for infertility care with a trusted friend or family member. If you find it difficult to have this discussion, find a peer support group or a health care provider who can provide truthful and accurate information.
- In addition to talking with your infertility specialist, consider consulting the obstetrician who will help you through your pregnancy and the pediatrician who will take care of your children. You may want to discuss what to expect during the pregnancy, at delivery, and after giving birth if you have a multiple pregnancy, and use that information in deciding whether to ask for eSET.
What can I do to avoid multiple birth?
If eSET seems appropriate to your circumstances, here are some things you can do.
- If you are using insurance or other benefits for infertility care, check with your carrier to determine if they have a “case manager” or “benefits counselor” who can guide you through understanding coverage or special considerations for eSET services.
- When selecting an ART provider, ask for information about the clinic’s policy and practices, as well as resources for decision making (e.g., counseling, case management).
- Ask when you must make choices, or will have time to reconsider decisions, and how long you will have to make the decision (e.g., a day, an hour, a week).
There will be many decisions to make and uncertainty about the outcomes. In the end, it will remain important to take care of yourself, whether you will be the person who carries the pregnancy or a person who will become a parent through this process.
We understand the journey to overcoming infertility can be a long one, and making the decision to pursue ART can be overwhelming. It is important to know the implications of all decisions you will make, especially those that present health risks during and after pregnancy. You also need to give yourself time to consider if the options you seek are consistent with your needs, values, and beliefs.