Chilling without regrets: Deciphering the effects of cryopreservation on the epigenetic properties of frozen cells will benefit the applications of cryo-technology.

In 2014, Facebook and Apple announced that they would pay for female employees to have their oocytes frozen to allow them to delay having children and instead focus on their careers. Whatever motivated the companies to make their offers, the fact that they did so highlights a prevalent problem faced by many young women: Their most fertile years are also a crucial period for building a career, when time off work may disadvantage them. > … cryopreservation is known to affect cell survival after thawing, which can have an impact on the subsequent clinical applications of frozen cells. To fulfill their offers, Facebook and Apple will need to offer their employees access to cryopreservation technologies that profoundly change the dynamics of family planning. Such technologies are not new, but work over the past decades has been aimed at increasing safety and efficacy and has reduced costs to the point that companies can now offer cryopreservation as a way to attract and retain female workers. Of course, the potential of cryopreservation goes far beyond freezing the eggs or sperm of ambitious young technology workers—it is a ubiquitous technology used in research and medicine for a wide variety of applications (Fig 1). For example, cryopreservation is used to store and transport biological material, including adult stem cells or stem cells from umbilical cord blood or bone marrow—both of which can later be used to treat disease or extend lifespan in the same patient—blood donations, especially of rare blood types, tissues, and organs. It is also offered as a crucial service for cancer patients to preserve their gametes before they undergo therapy that may render them infertile and, generally used in assisted reproduction to store oocytes, fertilized eggs, or embryos. Cryopreservation can contribute to environmental preservation efforts, where it is used to conserve the …