Embryo freezing is a way to store embryos for later use, for many reasons. Freezing embryos can allow for fertility preservation, future pregnancies, genetic testing, and more. Here are five common reasons why patients freeze their embryos.

1. Decrease the Number of Egg Retrieval Procedures

The in vitro fertilization (IVF) process often results in the collection of multiple eggs and, if fertilized, then multiple embryos. Usually, clinics transfer only one embryo per cycle, which can result in several viable embryos left over. At the same time, it often takes more than one IVF cycle to become pregnant. For this reason, many patients choose to freeze and store any additional embryos to use in later IVF attempts. This can reduce the time and expense of future cycles by potentially removing the need for additional egg retrievals.

2. Decrease Risk of Multiple Gestations 

Carrying a multiple pregnancy (such as twins or triplets) significantly increases risks for both the mother and babies. Single-embryo transfers reduce the risk of a multiple pregnancy. There is such a high success rate with a single embryo transfer, and so much experience with frozen embryo transfer cycles, that there is no need to risk the chance of a multiple gestation pregnancy.

Freezing embryos, rather than multiple pregnancies, can also help intended parents who would like to have more than one child. Frozen embryos can be safely stored for years before being thawed and transferred to try for another child. As IVF success is closely tied to the age at which eggs or embryos are frozen, using previously frozen embryos can improve the chances of a successful pregnancy at a later age. 

Relatedly, intended parents using donor eggs or sperm may wish to develop and freeze additional embryos to have the option of biological siblings, as eggs or sperm from the same donor might not be available years later.

3. Fertility Preservation

Fertility preservation involves freezing reproductive tissue (eggs, sperm, or embryos) to provide options for pregnancy in the future. Patients may choose fertility preservation because:

• They are about to go through chemotherapy, gender affirmation therapy, or other medical treatments that may affect their reproductive system
• One or both partners is about to leave for active military service
• They want to delay having children until later in life, when it is harder to get pregnant without medical assistance

4. Genetic Testing

IVF offers the option of genetic testing before transferring an embryo to the uterus. The most common form, preimplantation genetic testing (PGT-A), screens embryos for abnormal chromosome development, which is a common cause of unsuccessful implantation or miscarriage. In PGT-A, an embryologist takes a small sample of tissue from each embryo, then processes the samples over the next 10-14 days. Embryos undergoing PGT-A are frozen and stored immediately after testing to preserve them at the optimal stage for implantation while the results process.

5. Embryo Donation

Some patients may have embryos left over even after they finish fertility treatment and don’t intend to go through any future cycles. In these cases, they have the option to either discard the embryos or donate them to other intended parents. Embryo donation is similar to egg and sperm donation, and is an option for intended parents who struggle to conceive using their own eggs or sperm. Donating your additional embryos is a deeply personal decision. If you’d like to learn more, our counselors can help guide you through the many factors to consider.

Embryo Freezing is Safe and Effective

Freezing and storing embryos can provide additional options and flexibility throughout your fertility journey. Our embryologists develop and cryopreserve embryos in our in-house lab, which provides state-of-the-art services with the highest quality assurance. Embryo cryopreservation has been demonstrated to be safe and effective, with similar success rates as fresh embryo transfers. For more information about embryo freezing, contact us today.