Abstract

To investigate the relationship between air bubble position after blastocyst transfer (BT) and pregnancy rates (PRs).Retrospective cohort study.University-based infertility center.Three hundred fifteen consecutive nondonor BTs by a single provider.Catheters were loaded with 25 µL of culture media, 20 µL of air, 25 µL of media containing the blastocysts, 20 µL of air, and a small amount of additional media. The distance from the air bubble to the fundus, as seen on abdominal ultrasound examination, was measured at the time of transfer. Air bubble location was categorized as <10 mm, 10-20 mm, and >20 mm from the fundus.Clinical pregnancy rate.After controlling for age, parity, FSH and frozen transfers, and accounting for repeated cycles per patient, the PRs for both the >20-mm (38.3%) and the 10-20-mm (42.0%) from the fundus group were significantly reduced compared with the group in which the bubble was <10 mm from the fundus (62.5%).This study is the first to suggest that BT closer to the fundus is associated with higher PR. Although no ectopic pregnancies occurred in the <10-mm group, this outcome should be monitored closely in larger studies.

View details for DOI 10.1016/j.fertnstert.2010.07.1063

View details for Web of Science ID 000287480300019

View details for PubMedID 20810105