Freezing embryos is a standard practice when it comes to the IVF and surrogacy process. Many egg donors will produce many viable eggs that go on to become embryos with a high probability to implant and become viable pregnancies. As a result, you’re likely to have too many great looking embryos than you need come transfer day. The question then becomes, “What do we do with the left over embryos?”
The most common choice is to have the embryos frozen. This choice allows you to “bank” the embryos in the result of a failed transfer, miscarriage, or a potential future sibling project! If you do choose to freeze unused embryos, you’ll likely wonder how long they’re able to be usable after being frozen.
The first instance of freezing a frozen embryo resulting in a successful pregnancy was in 1983. To date, the longest frozen embryo to result in a live birth was on ice for 13 years before being thawed and transferred into a uterus. Research suggests that a frozen embryo can be kept viable for an extremely long period of time so long as freezing conditions remain favorable and consistent.
Freezing the embryo generally takes a couple of hours. Once frozen, the embryos will be kept in a tube surrounded by liquid nitrogen ensuring that the temperature stays around -320 degrees. Later, when the embryos are desired for transplant, thawing takes about a day. Once brought to room temperature, the embryos will be placed in an incubator to be kept at 98.6 degrees for up to a day while they await transfer.
With the knowledge that your unused embryos are likely to remain viable for decades, the more pressing question will be how long you intend to keep your embryos. While some parents will choose to retain their embryos indefinitely, others may not want to continue to incur the annual charges to retain their frozen embryos once they are certain that their family is completed. In this instance you will have the choice to either discard the embryos, or to donate them either to science or another couple in need.
Your case specialist will be able to talk with you about all of these options and help you decide which is best for you and your growing family.