In two-thirds of in vitro fertilization (IVF) procedures in the U.S., three or more embryos are transferred. This can increase the chances of multiple pregnancies, with triplets, quadruplets, or more. To prevent the risks associated with multiple births, experts recommend elective single embryo transfer (eSET).
Who is a candidate for elective single embryo transfer?
The American Society for Reproductive Medicine (ASRM) recommends eSET for:
• Women who are aged 35 years and younger
• Females who have good embryo quality
• Women undergoing their first assisted reproductive technology (ART) cycle
• Females with a favorable diagnosis
• Women who had a successful pregnancy in an earlier ART cycle
• Females who have embryos available for later use (cryopreservation)
What are the risks associated with multiple embryo transfers?
When the fertility specialist transfers multiple embryos (three or more), there is an increased risk for multiple pregnancies. For the mother, risks include heart problems, gestational diabetes, placenta previa, preterm labor, pre-eclampsia, and iron deficiency anemia. For the baby, the complications and long-term health problems associated with multiple pregnancies include:
• Lung problems
• Cerebral palsy
• Intellectual disabilities
• Vision and/or hearing loss
How is the elective single embryo transfer performed?
The procedure for eSET is the same as that for conventional in vitro fertilization. The woman is first given hormones to increase egg production. Once eggs have matured, they are collected and mixed in the laboratory with sperm. After the fertilization process, the doctor selects the embryo and transfers it to the woman’s uterus.
What is the success rate of single embryo transfer?
According to statistics from the Pacific Coast Reproductive Society, use of single embryo transfer has increased the pregnancy rate of IVF to 82%, and the rate of live birth to 79%.
Is eSET right for me?
Based on research studies, women who choose elective single embryo transfer have similar live-birth deliveries compared to those who use multiple embryos for the procedure. Any woman under 35 years of age who wishes to avoid multiple pregnancies would benefit from eSET. Making a decision to use assisted reproductive technology is confusing, so discuss options with your fertility specialist. Make sure your decisions are consistent with your values, needs, and beliefs.
The fertility specialist selects the highest-quality embryo for the transfer, and this is done based on appearance in the laboratory. The assessment includes number and size of cells, as well as the rate of development. No selection method can adequately predict if or not the embryo attach to the uterine wall and sustain life.
What technology is behind eSET?
Elective single embryo transfer uses a combination of approaches to increase the chances of pregnancy. These include:
• Extended embryo culture – This allows the embryo to be at a more advanced stage, so selection of the highest quality is possible.
• Time-lapse photography – This is used to identify embryos with normal cells division without having to remove them from the controlled environment.
• Comprehensive chromosome screening – Safely and reliably selects an embryo with normal chromosome counts.
• Vitrification – One embryo at a time can be warmed after freezing.