What Happens to Leftover Embryos?
Many egg donors are curious about what will happen to their eggs following their donation. While you probably expect that your eggs will be fertilized in an attempt to create as many viable embryos as possible, you may not realize that not all of those embryos will be used.
In most cases, fertility doctors will transfer between one and two embryos into the uterus at a time. Occasionally, your donation may only yield one or two high quality embryos, leaving none left over following the transfer. It is more common that a single donation will result in multiple high grade embryos. This situation often leaves several embryos “left over” that are viable but are not transferred at the time of fertilization.
In most cases, the higher quality embryos will be cryogenically frozen to be used in future transfers. This means the intended parents will have embryos ready for use, if this first transfer doesn’t result in a viable pregnancy. These frozen embryos can be thawed months or even years later with the intention of creating a biological sibling.
Even if embryos are later thawed for use, there often are leftover frozen embryos at the close of the IP’s family building journey. If this is the case, the intended parents will have the choice of what happens to these embryos. Choices include:
- Continuing to keep the embryos frozen
- Thaw the embryos and discard them
- Donate embryos to science
- Donate embryos to other couples
It is important for you to understand at the onset of your donation that this choice will be made by the intended parents. You will not have any input with this decision. Additionally, it is unlikely that you will have any knowledge of how many embryos were created, used, or leftover.