Human blastocysts immediately after thawing (upper panel) and at the time of transfer (lower panel). Two of three embryos re-expanded within four hours and the transfer resulted in a twin pregnancy.
Human hatched blastocyst that developed in culture after vitrification with VS14 at the day 2 cleavage stage.(Ali et al., J. Reprod. Fertil. 99:65,1993; Ali, Med. Sci. Res. 24:377, 1996)