Before your egg retrieval, Dr. Branigan will obtain the consent of both partners to cryopreserve (freeze) any extra embryos for thawing and replacement in a later cycle. Cryopreservation is used to minimize the risk of multiple gestations (twins, triplets, etc) which increase if more than four embryos are replaced. This process also allows us to optimally utilize all the embryos created during a single IVF cycle.

Embryos that meet developmental criteria can be frozen at several stages. The freezing process is computer controlled and requires the use of special solutions to protect the fertilized eggs from damage. Frozen embryos are stored at -196 degrees C or approximately -400 degrees F below zero. Cryopreservation is often used when more embryos are available than are needed for a single IVF transfer. Embryo Cryopreservation can provide a second or even third opportunity for pregnancy without repeating the entire IVF stimulation process.

As with semen Cryopreservation, many embryos do not survive the freezing and thawing process. Those that do survive may produce an ongoing pregnancy at somewhat of a lower rate than fresh embryos. There is no known increase in spontaneous miscarriages or birth defects from pregnancies which are the result of previously frozen and thawed embryos.