Outcome of closed blastocyst vitrification in relation to blastocyst quality: evaluation of 759 warming cycles in a single-embryo transfer policy

Abstract

Successful cryopreservation of blastocysts from the early cavitating up to expanded blastocyst stages is possible using a closed HS device. The choice between single or double frozen blastocyst transfer should depend on blastocyst expansion after vitrification.