The process of cryopreservation offers patients one or more extra efforts to achieve a pregnancy with only one cycle of ovarian stimulation. When many good quality embryos are created from one cycle of IVF, there is a possibility to freeze some of them.

The embryos may be frozen at different times after fertilization. Usually, the embryos are frozen on the first, second or third day after fertilization or at the blastocyst stage. Embryos are frozen in a special cryoprotectant medium and stored in liquid nitrogen.

Freezing is a very traumatic and stressful process for embryos, and fetuses do not survive much after thawing. So, we only freeze embryos that are of a very good quality and when we believe that they will survive the process of freezing and thawing.
Apart from freezing embryos, in some cases eggs or spermatozoa can be frozen for various reasons. For example, some women wish to delay their pregnancy, or patients with problems that might affect their fertility (e.g. treatment for cancer), etc.