History
Cryopreservation itself has always played a central role in assisted reproductive technology. With the first cryopreservation of sperm in 1953 and of embryos thirty years later, these techniques have become routine. Dr Christopher Chen of Australia reported the world’s first pregnancy in 1986 using previously frozen oocytes. This report stood alone for several years followed by studies reporting success rates using frozen eggs to be much lower than those of traditional in vitro fertilization (IVF) techniques using fresh oocytes. Then recently, two articles published in the journal, Fertility and Sterility, reported pregnancy rates using frozen oocytes that were comparable to those of cryopreserved embryos and even fresh embryos. These newer reports affirm that oocyte cryopreservation technology is advancing.
Almost 42,000 'slow frozen' (as opposed to 'vitrified') human embryo transfers were performed during 2001 in Europe (Andersen et al. 2005). In addition, it is estimated that between 300,000 and 500,000 successful human births have resulted worldwide from the transfer of previously ‘slow frozen’ embryos performed from the mid-1970s to 2006.
Read more about this topic: Oocyte Cryopreservation
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