Air in the uterine cavity after embryo transfer.

OBJECTIVE

To examine the effect on the pregnancy rate (PR) caused by air bubbles loaded into the transfer catheter to bracket the embryo-containing medium.

DESIGN

Prospective, randomized study.

SETTING

One hundred ninety-six consecutive ETs in the Institute of Sterility Treatment.

INTERVENTIONS

Air bubbles were loaded into the transfer catheter concomitantly with the medium in group I (n = 98), whereas in group II (n = 98) no air bubbles were used.

RESULTS

The PR of group I equals that of group II.

CONCLUSIONS

Bracketing the embryo-containing medium by air bubbles offers several advantages, especially the possibility of tracking the air on the ultrasound monitor to localize the embryos after the ET. For these reasons we recommend using the proven method.