Effect of air bubbles localization and migration after embryo transfer on assisted reproductive technology outcome.

OBJECTIVE: To evaluate the effect of embryo flash position and movement of the air bubbles at 1 and 60 minutes after ET on clinical pregnancy rates (PRs).

DESIGN: Prospective clinical trial.

SETTING: University fertility clinic.

PATIENT(S): A total of 230 fresh ultrasound-guided ETs performed by a single physician (C.F.) at the IVF center of Yeditepe University Hospital between September 2016 and February 2017 were included.

INTERVENTION(S): Transabdominal ultrasonographic guidance at ET.

MAIN OUTCOME MEASURE(S): Clinical PRs.

RESULT(S): There was no significant difference in terms of clinical PRs between women with embryo flash located >15 mm and <15 mm from the fundus at 1 or 60 minutes (P=.6 and P=.7, respectively). The PRs in women with embryo flash located <15 mm and >15 mm from the fundus were 47% and 60%, respectively (P=.6). The clinical intrauterine PRs were 69.5%, 38.5%, and 19.1% in fundal, static, and cervical, respectively. The highest PR was in fundal when compared with others (P<.01). The clinical PR appears to be associated with the embryo flash movement/migration and the PR was dramatically reduced when the embryo migrated from its original position toward the cervix at 60 minutes.

CONCLUSION(S): We concluded that clinical PR appears to be associated with the embryo flash movement/migration at 60 minutes after ET and embryo flash movement toward the fundus is associated with higher clinical PRs. Further well-designed randomized controlled trials are required to optimize ET technique in the future.