Enhanced hatching rate of bovine IVM/IVF/IVC blastocysts using a 1.48- μm diode laser beam

Abstract

Purpose: Our purpose was to test whether zona pellucida (ZP) drilling using a 1.48-μm diode laser beam on bovine IVM/IVF/IVC blastocysts is effective for embryo hatching. Methods: Blastocysts produced in vitro at day 7 after IVF were divided into control and laser-drilled groups, respectively. Results: When the rates of in vitro development of bovine embryos were examined, the average cleavage rate (≥two-cell) was 82.3% and the blastocyst rate at day 7 after IVF was 32.5%. Using these blastocysts, when the laser drilling effect was investigated at 48 hr after treatment, the total hatching rate in the laser-drilled group (98.0%) was significantly higher than that in the control group (60.0%)(P < 0.001). Especially the hatched rate of the laser-drilled group (68.0%) was significantly enhanced compared with that of the control group (30.0%) (P < 0.001). Conclusions: These results demonstrated that laser ZP drilling on bovine IVM/IVF/IVC blastocysts can significantly increase the hatching rate.