Effects of different biopsy methods on the development of preimplantation mouse embryos, in vitro and in vivo: implication for preimplantation genetic diagnosis.

The aim of this study was to investigate the efficacy of two different embryo biopsy techniques, direct aspiration and partial zona dissection (PZD)-push, on subsequent in vitro and in vivo development of 8-cell stage mouse embryos. It was found that the rates of normal blastocyst formation and hatching blastocysts of direct aspiration, PZD-push, solution control and control embryos were not significantly different (80.8%, 81.6%, 84.5%, 86.7% and 71.9%, 72.3% and 74.6%) respectively. There was, however, a significant reduction in rate of complete hatching blastocysts (P < 0.1) (72.9% aspiration versus 85.2 per cent solution control and 86.4% control) and rate of live-born fetuses (24.2% aspiration versus 43.3% solution control and 41.2% control) (P < 0.05) in the direct aspiration group but no significant difference in the PZD-push group (80.3% of complete hatched blastocysts and 33.8% of live-born fetuses). These findings indicated that embryo biopsy with PZD-push was superior to the direct aspiration method. This mouse embryo biopsy model was useful in advancing development of biopsy technique for human preimplantation genetic diagnosis.