If a couple undergoing in vitro fertilization receives a larger number of quality embryos that will not be transferred in this cycle, there is a possibility to freeze them (cryopreservation) and store them in a liquid nitrogen bank at -196℃ without reducing their quality. These frozen embryos are used for further procedures of returning embryos in a natural cycle, without the patient having to go through the complete process of hormonal stimulation, egg retrieval, and in vitro fertilization. The survival rate of quality embryos after thawing from vitrification (rapid freezing) used in our center guarantees up to 99% that your embryo survives and is ready for transfer to the uterus.
According to the latest ESHRE guidelines, it is indicated to return only one quality blastocyst, and therefore our center's practice is to freeze only one blastocyst in one straw, so that what we thaw can also be returned. In the case of freezing 2 blastocysts, done before the ESHRE directive, if the second blastocyst is of good quality, we will freeze it again.
Is there a risk to the future health of a child born from an embryo that was frozen?
Research has not proven that there is a difference in the psychophysical health of babies and subsequently children and adolescents born through the transfer of embryos that were previously frozen and spontaneously conceived children.