Blastocyst Embryo Transfer

A blastocyst is the name given to an embryo that is 5-6 days old. A blastocyst embryo transfer does not differ from a normal embryo transfer but simply refers to the age of the embryo in terms of its development at the stage of transfer.

Who is suitable for a blastocyst transfer?

Not all patients are suitable for a blastocyst transfer. Some patients may benefit from an early transfer rather than continued growth to a blastocyst stage especially if they have a very small number of good quality embryos. However, a blastocyst transfer can be an option for patients with multiple embryos.

Blastocyst stage embryos do have a higher chance of achieving a pregnancy compared to day 3 embryos. This can be attributed to the fact that the embryos have undergone a further selection process of eliminating embryos that have failed to develop into blastocysts. Typically around 60% of day 3 embryos will develop to the blastocyst stage.

What are the risks associated with a blastocyst transfer?

One of the risks associated with a blastocyst embryo transfer is that there is a higher rate of cancellation of the cycle as there may be no embryos being available for transfer due to no blastocyst formation). A blastocyst transfer has also been associated with a higher rate of monozygotic (identical) twins.