Influence of embryo transfer on embryo preimplantation development

Abstract

Objective: To investigate the impact of injection speeds of the transferred load on embryo development.

Design: A laboratory model for in vitro simulation of ET was developed to investigate the impact of varying injection speeds of the transferred load on embryo development.

Setting: Academic research institutes of reproduction biotechnology and private centers of reproductive medicine.

Animal(s): Mouse hybrid F(1) females (C57bl/10 J × CBA-H; N = 15) aged 2-3 months.

Intervention(s): In vitro exposure of mouse embryos with either the fast ET (ejection speed, >1 m/s) or slow ET (ejection speed, <0.1 m/s) and consecutive culture for 36 hours.

Main outcome measure(s): Development rate, morphology and apoptotic index of embryos.

Result(s): The development rate was the slowest in embryos exposed to the fast ET. Morphological changes in response to ET were observed only among embryos exposed to the fast ET. The mean apoptotic index was 17.6% in the group exposed to the fast ET, 5.6% in the group exposed to the slow ET, and 2.58% in the control group.

Conclusion(s): A reduction of the ejection speed of the transferred load allows avoidance of a developmental delay and diminishes injury of the embryos. Therefore, it is reasonable to suggest transferring the embryos at the lowest possible ejection speed.