Many of the steps of in vitro fertilization are involved in embryo cryopreservation and they are multiple follicle stimulation with FSH, premature LH surge prevention with a GnRH analogue, triggering the process of ovulation, oocyte retrieval, fertilization with sperm and cryopreservation of embryos.
Embryo cryopreservation requires the presence of a male partner or a sperm from a donor. Oocyte retrieval from the woman is the first step of this process. Later the oocyte is fertilized in vitro with her partner's or donor's sperm. After that, cryoprotectants are applied to the embryos and they are stored at subzero temperatures until they are ready to be used.
The embryo is thawed, and implantation plans are formed after the decision to use it is made.