frozen embryo transfer

Frozen Embryo Transfer

A frozen embryo transfer, commonly referred to as FET, is the process of using a frozen embryo from a previous IVF cycle. It’s gaining popularity due to its safety and pregnancy success rates. During this procedure, a woman undergoes the standard IVF procedure, but instead of transferring the embryos back into the uterus in the same cycle, they are frozen for use in a future cycle. A woman can freeze her own eggs or choose to use donor eggs. The eggs are transferred in a later cycle to help the woman recover from her current IVF cycle and reduce the effect of desynchronization.
Frozen Embryo Transfer

Frozen Embryo Transfer and Desynchronization in IVF

During the menstrual cycle, estrogen levels naturally peak just before ovulation. This rise in estrogen triggers ovulation and causes the ovaries to begin producing progesterone. Progesterone then triggers the development of the endometrial lining of the uterus.

For a pregnancy to develop, a fertilized egg needs to implant in the endometrial lining and begin to grow. Because the body produces progesterone in response to ovulation, in ideal conditions, the endometrial lining develops at the right rate to nurture the fertilized egg. That synchronization between the progesterone response and endometrial lining development creates the best environment for implantation.

However, during IVF treatment, the ovaries are stimulated, and estrogen levels peak at much higher levels than in natural cycles. This artificially-induced peak in estrogen triggers progesterone production.

Sometimes, progesterone levels increase too early, and the endometrial lining develops too quickly to support the embryos. This desynchronization between an embryo and endometrial lining reduces the likelihood of a successful implantation. One reason why IVF patients take medications: to suppress progesterone production. In some patients, however, these medications do not work, and they may still have problems with cycle desynchronization.

Frozen Embryo Transfer and Desynchronization in IVF

How Frozen Embryo Transfer Works With IVF

FET is one way that we can avoid desynchronization. Delaying embryo transfer until a later cycle allows your hormones to normalize before proceeding and may give you a better chance at pregnancy. Instead of implanting embryos while the body is still recovering from IVF, embryos are created and frozen. Once the body has had a chance to recover from the stress of IVF and has returned to a more normal cycle, the embryos are thawed and implanted. This procedure is also used by families who wish to choose the gender of their child. They may want to do so to ensure a balanced representation of the sexes, or for any other reason. During the first cycle, the embryos are created, biopsied, tested and then frozen. An embryo transfer is scheduled at a later date, once the biopsy results have been returned and the female partner has recovered from her egg retrieval.

Frozen Embryo Transfer vs. Fresh Embryo Transfer

A fresh embryo transfer occurs in the same cycle as the IVF cycle. The eggs are retrieved and fertilized in the lab. The embryos are allowed to develop and are then transferred back into the woman’s uterus around 5-6 days after the retrieval. A frozen embryo transfer is a little bit different. In this type of cycle, a woman undergoes IVF, her eggs are retrieved and fertilized in the lab, and the resulting embryos are allowed to develop. On day 5 or 6, the embryos are frozen instead of being transferred back into her uterus. Preimplantation genetic testing can be performed on the embryos before they are frozen to screen for common chromosomal diseases, and also to identify the gender of the embryo. The transfer would occur once these results came back.

What is the Success Rate of a FET in IVF?

Freezing techniques such as the vitrification method have advanced significantly in recent years to resemble natural conception and result in increased pregnancy and live birth rates, decreased miscarriages, and healthier babies. Older slow freezing technology yielded few vital embryos, but the advanced vitrification method used at Aspire substantially reduces loss rates.

What is the Cost of an Embryo Transfer?

We strongly believe in the benefits that come with delaying an embryo transfer that we have included it as part of our standard of care for all IVF cycles. We offer it to our patients without any additional cost.

Am I a Candidate for FET?

Many women are candidates for and would benefit from this type of transfer. We encourage you contact us with any questions or book an appointment with a fertility expert at one of our three convenient locations in Houston, Dallas or Atlanta to learn more about this procedure and whether it’s the right option for you!