Effect of laser-assisted three area zona thinning at the 8-cell embryo on the hatching of mouse blastocysts

Abstract

Effect of laser-assisted three area zona thinning at the 8-cell embryo on the hatching of mouse blastocysts J.-K. Joo 1 , J.-E. Jeong 1 , H.-G. Kim 1 , S.-C. Kim 1 , C.-W. Kim 2 , K.-S. Lee 1 1Department of Obstetrics and Gynecology, Medical Research Institute, Pusan National University School of Medicine, Busan 2Department of Obstetrics and Gynecology, Sungkyunkwan University School of Medicine Samsung Changwon Hospital, Changwon (Korea) Summary Introduction: This study was aimed to preliminarily examine the effect of laser-assisted three area zona thinning (LAZT) during the cleavage stage of embryo development and the hatching process in mice based on female age. Materials and Methods: C57BL female mice of two different age groups (6-11 and 28-31 weeks) were superovulated and then mated. The 8-cell stage embryos were treated with LAZT in three areas of zona pellucida (ZP) at 120º intervals. The control group was embryos without LAZT. Results: In old mice, LAZT significantly increased blastocyst formation and hatching compared to the control group (82% vs. 38% in number of expanding blastocyst and 66% vs. 20% in number of hatching blastocyst). Conclusion: These results show that multi-area LAZT results in a significant improvement of blastocyst formation and hatching in mice compared to controls. Key word: Hatching; IVF; Laser.