Objective: To determine whether transabdominal ultrasound guidance during embryo transfer (ET) is a useful tool for increasing pregnancy rates in patients undergoing oocyte donation.
Design: Prospective, randomized, controlled trial.
Setting: In vitro fertilization academic center.
Patient(s): Three hundred seventy-four infertile patients undergoing oocyte donation.
Intervention(s): Transabdominal ultrasound-guided ET.
Main outcome measure(s): We measured the pregnancy rate and implantation rate after transabdominal ultrasound-guided ET versus the rates in a control group who did not receive transabdominal ultrasound-guided ET.
Result(s): Clear visualization at ultrasound during ET was achieved in 90.8% of the patients who had ultrasound-guided ET. A similar number of easy transfers were performed in both the ultrasound-guided and the control groups (84.5% vs. 86.6%). The pregnancy rate was comparable between the groups (59.9% ultrasound vs. 55.1% control), as was the implantation rate (30.6% ultrasound vs. 26.3% control). No differences were found in the miscarriage rate (10.7% ultrasound vs. 9.1% control) or in the multiple pregnancy rate (21.4% ultrasound vs. 22.5% control). Although all ectopic pregnancies occurred in the group that did not receive ultrasound guidance, the differences were not statistically significant (0 vs. 2.7%).
Conclusion(s): We could not show any benefit in terms of pregnancy rate in oocyte recipients for whom ET was performed under direct transabdominal ultrasound visualization of the endometrial cavity. There was a lower ectopic pregnancy rate when ultrasound guidance was used, but this rate was not statistically significant in comparison with the pregnancy rate without ultrasound guidance.