When the transfer is to be performed, it is important to have a receptive endometrium. It is a fairly safe process, so the risks are minimal. It is possible that difficulty in inserting the cannula and depositing the embryo may occur, as well as slight spotting after the procedure.
Another possible risk associated with embryo transfer is that the embryo may get stuck in the cannula. However, this is not a concern since the cannula is always checked later in the laboratory.