Fields across the board benefit from cryopreservation techniques. Now comes news that emerging cryopreservation techniques are giving hope to couples dealing with fertility problems. This is particularly true for women, whose reproductive tissue has been damaged by diseases like ovarian cancer. Cryopreservation is the process by which tissues or cells are preserved by cooling to low sub-zero temperatures (it may be as low as -196ºC). This process effectively stops any biochemical reactions that would trigger cell death. The European Science Foundation (ESF) recently organised a workshop highlighting cryopreservation of ovarian tissue. Researchers believe that these latest cryopreservation techniques can be used not only on humans, but on farm animals as well. The main benefit is the maintenance of banks of ovarian tissue and farm animal stocks. For animals in particular, it bolsters researchers' efforts to fight the extinction of endangered animal species. During the workshop, experts touched on how related fields of research concerning animal and human ovarian tissue preservation are being joined to support each other. Until now, researchers have focused on these two fields separately. Not only could the human and animal cryopreservation fields learn a lot from each other, but progress will be faster thanks to their growing collaboration, said the workshop convenor of the ESF. 'Experiments which cannot be performed in women can be done in animal species,' explained Dr Claus Yding Andersen of the University Hospital of Copenhagen, Denmark. 'Much of the progress in humans has come as a result of animal experiments.' Dr Andersen pointed out, however, that the most successful transplantations of frozen ovarian tissue after thawing out have been seen in humans. Consequently, it is where 'the greatest experience in the field has been gained'. The workshop members aimed to assess how to best use this knowledge for the animal cryopreservation field, and especially in the conservation of endangered species. 'The vast experience in women, with several children born as a result of transplantation of frozen/thawed ovarian tissue, can be applied in endangered species to know where to implant and how to obtain pregnancies,' Dr Andersen commented. Just as significant is that the ovaries of farm animals can be preserved in tissue banks via these latest techniques, effectively recreating the animal in question. To date, 25 women from around the globe have participated in ovarian tissue transplants, and 5 have given birth to healthy babies (2 in Belgium, 2 in Denmark and 1 in Israel). Latest figures also show that 1,000 women worldwide have decided to have their tissue cryopreserved so as to preserve fertility. Researchers believe women will increasingly choose ovarian cryopreservation as the technology gains strength in years to come. The majority of the women who have undergone this technique had lost fertility after being treated for cancer. 'We are likely to see a lot more of this coming in the coming years, including development of techniques for fertility preservation using different approaches,' said Dr Andersen, a researcher at the University Hospital of Copenhagen in Denmark. Cryopreservation generally involves slow freezing so as to curb the damage caused by ice crystals that are formed in the follicles. But new developments in this field of research show that vitrification may generate better results. With vitrification, the ovarian tissue would be converted into a glass-like form and not be damaged by ice crystals.