How is blastocyst transfer different from traditional Day 2 or Day 3 embryo transfer?

Blastocyst transfer differs from traditional Day 2 or Day 3 embryo transfer in terms of embryo development stage at the time of transfer. In traditional embryo transfer, embryos are transferred into the uterus on either Day 2 or Day 3 after fertilisation, when they are still in the early stages of development. In contrast, blastocyst transfer involves transferring embryos on Day 5 or 6, when they have reached the blastocyst stage of development. This extended culture period allows embryologists to select the healthiest embryos with a higher chance of successful implantation and pregnancy.