Elective Single Embryo Transfer
These high pregnancy rates after CCS are achieved with transfer of a single embryo, compared to IVF, which requires multiple embryos to maintain pregnancy rates.
*Pacific Fertility Center CCS data from 2016 and historical IVF data
Elective Single Embryo Transfer (eSET)
Minimizing risks of pregnancy while maintaining high pregnancy rates are the goals of physicians and staff at Pacific Fertility Center. With the help of several new technologies, elective Single Embryo Transfer (eSET) is now an effective and safe way to build families, one healthy baby at a time. At PFC we elect to transfer one embryo in over 90% of patients.
What is eSET?
In short, eSET involves identifying an embryo with a high chance of successful pregnancy and transferring that single embryo to the uterus. The lab "freezes" (vitrifies) any other healthy embryos for future use.
The eSET program at PFC produces very high pregnancy rates. Using embryos conservatively in this way is a big part of PFC's strategy to create healthier singleton pregnancies.
What is the technology behind eSET?
The recent past has seen an explosion of new fertility technologies—many tested or introduced very early by PFC. Used in combination, advances like these have made it possible to identify and transfer or store embryos with the greatest potential for pregnancy:
- Extended embryo culture to day 5 allows development to a more advanced stage, where it is possible to select embryos of the highest quality.
- Time-lapse photography (Early Embryo Viability Assessment, Eeva™) identifies embryos with normal cell division without removing them from their controlled incubation environment.
- Preimplantation genetic testing for aneuploidy (PGT-A) reliably and safely identifies embryos with normal chromosome counts.
- Vitrification allows freezing and storage of viable embryos. One embryo at a time can be warmed for future transfer of single embryos.
CCS is really the big game changer. Embryo selection by conventional imaging techniques is not very selective. Under the microscope, an abnormal embryo can look just like a normal embryo.
CCS is much more selective. After in vitro fertilization, we send a few cells from each embryo to the genetics lab where chromosomes are counted. An embryo with a normal number of chromosomes is selected from the group for transfer.
Women who can benefit from CCS include those with:
- Recurrent miscarriage
- Clinical aneuploidy (Down syndrome) risk
- Multiple pregnancy risk
- Sex-linked genetic illness risk
What are the benefits of eSET?
In the past, the standard practice with in vitro fertilization (IVF) was to transfer more than one embryo at a time. That's because—before the advent of new technologies—transferring multiple embryos gave higher pregnancy rates.
But those higher rates came with risk—the increased the chance of twins, triplets, or higher-order pregnancies (multiple gestation)—which increased risks to both mothers and babies.
Today, pregnancy rates are very high with eSET, when only one embryo is transferred, but the risk of multiple gestations is greatly reduced.
Lower risk of complications
eSET greatly reduces multiple gestations, which lowers the risk of complications such as:
- Premature delivery, low birth weight, and death of the baby
- Long-term disabilities in the child such as cerebral palsy, intellectual disability, or vision and hearing loss
- Other complications linked with early delivery, such as problems with the baby's lungs, brain, intestinal tract, or nervous system
- Complications in the mother such as high blood pressure, high blood sugar, increased nausea and vomiting, other gastrointestinal problems, problems with bleeding after delivery
High chance of pregnancy
eSET produces high pregnancy rates with the transfer of fewer embryos after CCS, as reflected in this graph.
Who is a candidate for eSET?
At Pacific Fertility Center, eSET is an option for all patients that have a chromosomally normal embryo identified through CCS, and most egg donation recipients.
To help reduce the number of multiple pregnancies and to promote the birth of one baby at a time, the American Society for Reproductive Medicine (ASRM) and SART now recommend limiting the transfer of euploid embryos to 1 in patients of any age who have a favorable prognosis. To learn more about their recommendation, read our article here.
Discuss with your doctor whether or not you are a good candidate for eSET.
What is the procedure for eSET?
Similar to other types of transfers, this is what's involved with eSET:
- Embryos are produced through IVF and cultured to day 5, the blastocyst stage
- Embryos are vitrified for future transfer, or transferred fresh
- Arrive for transfer with a bladder at least half full. This helps with imaging of the uterus with abdominal ultrasound.
- If you have a cold, cough, or allergy, let us know, as you may need a cough suppressant.
- About 15 minutes before the procedure, your doctor will discuss whether eSET is a good option, as well as the total number and quality of embryos for transfer—now or in the future.
- The embryologist will confirm your identity—one of several measures taken to ensure the safety of your embryos.
- The entire process takes about 15 minutes and is similar to the experience of a Pap test. The doctor loads the embryo into a soft catheter and passes it through the cervix into the uterus. You may feel slight pressure or often nothing at all.
After the transfer, the nurse will gently position your legs together and slightly elevate them.
Follow the instructions you receive about post-transfer care. But remember that a successful pregnancy has more to do with the quality of the embryo than anything you do following the transfer.
Building families at PFC
eSET is one more way that the physicians and staff at Pacific Fertility Center help you build your family, one healthy baby at a time.