Figure 1: Embryo transfer is enhanced by the use of ultrasound guidance to place the embryos at the optimal uterine location. The small hyperechoic areas distal to the catheter tip represent microbubbles of air expelled from the transfer pipette and serve to visualize embryo placement. (Image courtesy of Dr Roger Stronell.) Reference: Mansour, R. T. and M. A. Aboulghar (2002). “Optimizing the embryo transfer technique.” Hum Reprod 17(5): 1149-53.