Vitrification of human blastocysts: an update

Area of Science:

• Reproductive Medicine
• Embryology
• Cryobiology

Background:

• Blastocyst transfer enhances pregnancy rates and embryo selection.
• Transferring fewer embryos reduces high-order multiple pregnancies.
• Vitrification is a key cryopreservation technique in assisted reproduction.

Purpose of the Study:

• To evaluate the efficacy and outcomes of blastocyst vitrification and transfer.
• To assess the survival, implantation, and pregnancy rates of vitrified blastocysts.
• To analyze the perinatal outcomes following the transfer of vitrified blastocysts.

Main Methods:

• Vitrification of 8449 blastocysts from 2453 patients between January 2004 and February 2009.
• Performed 1398 vitrified embryo transfers (VET) of day-5 and day-6 blastocysts.
• Monitored outcomes including embryo survival, implantation, clinical pregnancy, and perinatal data.

Main Results:

• Achieved a 96.3% blastocyst survival rate post-warming.
• Reported an implantation rate of 29.4% and a clinical pregnancy rate of 42.8% per VET.
• Documented 431 births from 348 deliveries with no significant adverse perinatal outcomes.

Conclusions:

• Blastocyst vitrification is a highly effective method for embryo cryopreservation.
• Vitrification provides flexibility in laboratory procedures and optimal cryopreservation.
• This technique supports successful IVF cycles with favorable pregnancy and perinatal outcomes.