Ultrasound guidance for human embryo transfer.

Embryo transfer is facilitated with ultrasound guidance. The 16 ultrasound-guided transfers were rated easier, and there was less catheter distortion, in comparison with 12 transfers guided by "clinical feel." The benefits we ascribe to ultrasound guidance are as follows: (1) transfers can be done with the patient supine in the lithotomy position; (2) the catheter tip is accurately positioned in the fundus of the uterine cavity; (3) the ejection of the transfer bubble into the uterus and its persistence during catheter removal and documented; and (4) the continuance of the bubble is comforting to the patient. Greater experience is needed before the impact of ultrasound-guided transfer can be correlated with the rate of pregnancy continuance.