How is embryo transfer performed and should ultrasound scanning be used to guide transfer?

Embryo transfer is performed in an operating theatre adjacent to the embryology lab where the embryos are being cultured. The procedure is similar in some ways to having a Pap smear performed and no anaesthetic is required. Legs are placed in supports and the neck of the womb is exposed using a speculum, identical to having a Pap smear. After cleaning the neck of the womb, a small tube is placed through the neck of the womb and into the lower aspect of the womb cavity. The embryologists then load the embryo into a second, even finer, tube using a microscope. This very fine tube is then threaded through the outer tube that was previously positioned within the womb, and when it is at precisely the right spot in the cavity, the embryo is released from the tube into the womb cavity.

It is strongly recommended that ultrasound scanning on the tummy be used during embryo transfer since there is very clear evidence that using ultrasound to guide the placement of the tube in the cavity prior to embryo release produces the best pregnancy success rates. To facilitate scanning on the tummy, a full bladder is required. The specialist scans on the tummy at the same time as the transfer is being performed to ensure that the embryo is released into the correct position within the womb.