There is no set of mandatory rules concerning sperm and egg donation at national level in the USA. Conversely, regulations vary from state to state. However, the majority follows the guidelines established by the ASRM (America Society for Reproductive Medicine).
Vitrification consists of quickly reducing the temperature to which an oocyte is exposed to -196 °C. The procedure takes place in liquid nitrogen and cryopreservants, which avoid the breaking of the egg’s cell membranes.
It’s possible to become a father after having suffered cancer. There are several strategies, but the best would be cryopreserving a sperm sample that will be used once the patient has got over the illness.
Blastocyst is the stage in which embryo implantation within the uterus occurs naturally. To reach this stage, the embryo is cultured up to day 5-6 by means of a sequential culture system.